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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/nios2/kernel | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/nios2/kernel')
-rw-r--r-- | arch/nios2/kernel/.gitignore | 2 | ||||
-rw-r--r-- | arch/nios2/kernel/Makefile | 26 | ||||
-rw-r--r-- | arch/nios2/kernel/asm-offsets.c | 74 | ||||
-rw-r--r-- | arch/nios2/kernel/cpuinfo.c | 195 | ||||
-rw-r--r-- | arch/nios2/kernel/entry.S | 568 | ||||
-rw-r--r-- | arch/nios2/kernel/head.S | 175 | ||||
-rw-r--r-- | arch/nios2/kernel/insnemu.S | 580 | ||||
-rw-r--r-- | arch/nios2/kernel/irq.c | 79 | ||||
-rw-r--r-- | arch/nios2/kernel/kgdb.c | 158 | ||||
-rw-r--r-- | arch/nios2/kernel/misaligned.c | 238 | ||||
-rw-r--r-- | arch/nios2/kernel/module.c | 137 | ||||
-rw-r--r-- | arch/nios2/kernel/nios2_ksyms.c | 45 | ||||
-rw-r--r-- | arch/nios2/kernel/process.c | 269 | ||||
-rw-r--r-- | arch/nios2/kernel/prom.c | 37 | ||||
-rw-r--r-- | arch/nios2/kernel/ptrace.c | 145 | ||||
-rw-r--r-- | arch/nios2/kernel/setup.c | 197 | ||||
-rw-r--r-- | arch/nios2/kernel/signal.c | 328 | ||||
-rw-r--r-- | arch/nios2/kernel/sys_nios2.c | 60 | ||||
-rw-r--r-- | arch/nios2/kernel/syscall_table.c | 18 | ||||
-rw-r--r-- | arch/nios2/kernel/time.c | 359 | ||||
-rw-r--r-- | arch/nios2/kernel/traps.c | 196 | ||||
-rw-r--r-- | arch/nios2/kernel/vmlinux.lds.S | 64 |
22 files changed, 3950 insertions, 0 deletions
diff --git a/arch/nios2/kernel/.gitignore b/arch/nios2/kernel/.gitignore new file mode 100644 index 000000000..bbb90f92d --- /dev/null +++ b/arch/nios2/kernel/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +vmlinux.lds diff --git a/arch/nios2/kernel/Makefile b/arch/nios2/kernel/Makefile new file mode 100644 index 000000000..78a913181 --- /dev/null +++ b/arch/nios2/kernel/Makefile @@ -0,0 +1,26 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the nios2 linux kernel. +# + +extra-y += vmlinux.lds + +obj-y += head.o +obj-y += cpuinfo.o +obj-y += entry.o +obj-y += insnemu.o +obj-y += irq.o +obj-y += nios2_ksyms.o +obj-y += process.o +obj-y += prom.o +obj-y += ptrace.o +obj-y += setup.o +obj-y += signal.o +obj-y += sys_nios2.o +obj-y += syscall_table.o +obj-y += time.o +obj-y += traps.o + +obj-$(CONFIG_KGDB) += kgdb.o +obj-$(CONFIG_MODULES) += module.o +obj-$(CONFIG_NIOS2_ALIGNMENT_TRAP) += misaligned.o diff --git a/arch/nios2/kernel/asm-offsets.c b/arch/nios2/kernel/asm-offsets.c new file mode 100644 index 000000000..e3d9b7b6f --- /dev/null +++ b/arch/nios2/kernel/asm-offsets.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> + */ + +#include <linux/stddef.h> +#include <linux/sched.h> +#include <linux/kernel_stat.h> +#include <linux/ptrace.h> +#include <linux/hardirq.h> +#include <linux/thread_info.h> +#include <linux/kbuild.h> + +int main(void) +{ + /* struct task_struct */ + OFFSET(TASK_THREAD, task_struct, thread); + BLANK(); + + /* struct thread_struct */ + OFFSET(THREAD_KSP, thread_struct, ksp); + OFFSET(THREAD_KPSR, thread_struct, kpsr); + BLANK(); + + /* struct pt_regs */ + OFFSET(PT_ORIG_R2, pt_regs, orig_r2); + OFFSET(PT_ORIG_R7, pt_regs, orig_r7); + + OFFSET(PT_R1, pt_regs, r1); + OFFSET(PT_R2, pt_regs, r2); + OFFSET(PT_R3, pt_regs, r3); + OFFSET(PT_R4, pt_regs, r4); + OFFSET(PT_R5, pt_regs, r5); + OFFSET(PT_R6, pt_regs, r6); + OFFSET(PT_R7, pt_regs, r7); + OFFSET(PT_R8, pt_regs, r8); + OFFSET(PT_R9, pt_regs, r9); + OFFSET(PT_R10, pt_regs, r10); + OFFSET(PT_R11, pt_regs, r11); + OFFSET(PT_R12, pt_regs, r12); + OFFSET(PT_R13, pt_regs, r13); + OFFSET(PT_R14, pt_regs, r14); + OFFSET(PT_R15, pt_regs, r15); + OFFSET(PT_EA, pt_regs, ea); + OFFSET(PT_RA, pt_regs, ra); + OFFSET(PT_FP, pt_regs, fp); + OFFSET(PT_SP, pt_regs, sp); + OFFSET(PT_GP, pt_regs, gp); + OFFSET(PT_ESTATUS, pt_regs, estatus); + DEFINE(PT_REGS_SIZE, sizeof(struct pt_regs)); + BLANK(); + + /* struct switch_stack */ + OFFSET(SW_R16, switch_stack, r16); + OFFSET(SW_R17, switch_stack, r17); + OFFSET(SW_R18, switch_stack, r18); + OFFSET(SW_R19, switch_stack, r19); + OFFSET(SW_R20, switch_stack, r20); + OFFSET(SW_R21, switch_stack, r21); + OFFSET(SW_R22, switch_stack, r22); + OFFSET(SW_R23, switch_stack, r23); + OFFSET(SW_FP, switch_stack, fp); + OFFSET(SW_GP, switch_stack, gp); + OFFSET(SW_RA, switch_stack, ra); + DEFINE(SWITCH_STACK_SIZE, sizeof(struct switch_stack)); + BLANK(); + + /* struct thread_info */ + OFFSET(TI_FLAGS, thread_info, flags); + OFFSET(TI_PREEMPT_COUNT, thread_info, preempt_count); + BLANK(); + + return 0; +} diff --git a/arch/nios2/kernel/cpuinfo.c b/arch/nios2/kernel/cpuinfo.c new file mode 100644 index 000000000..203870c4b --- /dev/null +++ b/arch/nios2/kernel/cpuinfo.c @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2013 Altera Corporation + * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> + * + * Based on cpuinfo.c from microblaze + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/seq_file.h> +#include <linux/string.h> +#include <linux/of.h> +#include <asm/cpuinfo.h> + +struct cpuinfo cpuinfo; + +#define err_cpu(x) \ + pr_err("ERROR: Nios II " x " different for kernel and DTS\n") + +static inline u32 fcpu(struct device_node *cpu, const char *n) +{ + u32 val = 0; + + of_property_read_u32(cpu, n, &val); + + return val; +} + +void __init setup_cpuinfo(void) +{ + struct device_node *cpu; + const char *str; + int len; + + cpu = of_get_cpu_node(0, NULL); + if (!cpu) + panic("%s: No CPU found in devicetree!\n", __func__); + + if (!of_property_read_bool(cpu, "altr,has-initda")) + panic("initda instruction is unimplemented. Please update your " + "hardware system to have more than 4-byte line data " + "cache\n"); + + cpuinfo.cpu_clock_freq = fcpu(cpu, "clock-frequency"); + + str = of_get_property(cpu, "altr,implementation", &len); + if (str) + strlcpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl)); + else + strcpy(cpuinfo.cpu_impl, "<unknown>"); + + cpuinfo.has_div = of_property_read_bool(cpu, "altr,has-div"); + cpuinfo.has_mul = of_property_read_bool(cpu, "altr,has-mul"); + cpuinfo.has_mulx = of_property_read_bool(cpu, "altr,has-mulx"); + cpuinfo.has_bmx = of_property_read_bool(cpu, "altr,has-bmx"); + cpuinfo.has_cdx = of_property_read_bool(cpu, "altr,has-cdx"); + cpuinfo.mmu = of_property_read_bool(cpu, "altr,has-mmu"); + + if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div) + err_cpu("DIV"); + + if (IS_ENABLED(CONFIG_NIOS2_HW_MUL_SUPPORT) && !cpuinfo.has_mul) + err_cpu("MUL"); + + if (IS_ENABLED(CONFIG_NIOS2_HW_MULX_SUPPORT) && !cpuinfo.has_mulx) + err_cpu("MULX"); + + if (IS_ENABLED(CONFIG_NIOS2_BMX_SUPPORT) && !cpuinfo.has_bmx) + err_cpu("BMX"); + + if (IS_ENABLED(CONFIG_NIOS2_CDX_SUPPORT) && !cpuinfo.has_cdx) + err_cpu("CDX"); + + cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways"); + if (!cpuinfo.tlb_num_ways) + panic("altr,tlb-num-ways can't be 0. Please check your hardware " + "system\n"); + cpuinfo.icache_line_size = fcpu(cpu, "icache-line-size"); + cpuinfo.icache_size = fcpu(cpu, "icache-size"); + if (CONFIG_NIOS2_ICACHE_SIZE != cpuinfo.icache_size) + pr_warn("Warning: icache size configuration mismatch " + "(0x%x vs 0x%x) of CONFIG_NIOS2_ICACHE_SIZE vs " + "device tree icache-size\n", + CONFIG_NIOS2_ICACHE_SIZE, cpuinfo.icache_size); + + cpuinfo.dcache_line_size = fcpu(cpu, "dcache-line-size"); + if (CONFIG_NIOS2_DCACHE_LINE_SIZE != cpuinfo.dcache_line_size) + pr_warn("Warning: dcache line size configuration mismatch " + "(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_LINE_SIZE vs " + "device tree dcache-line-size\n", + CONFIG_NIOS2_DCACHE_LINE_SIZE, cpuinfo.dcache_line_size); + cpuinfo.dcache_size = fcpu(cpu, "dcache-size"); + if (CONFIG_NIOS2_DCACHE_SIZE != cpuinfo.dcache_size) + pr_warn("Warning: dcache size configuration mismatch " + "(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_SIZE vs " + "device tree dcache-size\n", + CONFIG_NIOS2_DCACHE_SIZE, cpuinfo.dcache_size); + + cpuinfo.tlb_pid_num_bits = fcpu(cpu, "altr,pid-num-bits"); + cpuinfo.tlb_num_ways_log2 = ilog2(cpuinfo.tlb_num_ways); + cpuinfo.tlb_num_entries = fcpu(cpu, "altr,tlb-num-entries"); + cpuinfo.tlb_num_lines = cpuinfo.tlb_num_entries / cpuinfo.tlb_num_ways; + cpuinfo.tlb_ptr_sz = fcpu(cpu, "altr,tlb-ptr-sz"); + + cpuinfo.reset_addr = fcpu(cpu, "altr,reset-addr"); + cpuinfo.exception_addr = fcpu(cpu, "altr,exception-addr"); + cpuinfo.fast_tlb_miss_exc_addr = fcpu(cpu, "altr,fast-tlb-miss-addr"); + + of_node_put(cpu); +} + +#ifdef CONFIG_PROC_FS + +/* + * Get CPU information for use by the procfs. + */ +static int show_cpuinfo(struct seq_file *m, void *v) +{ + const u32 clockfreq = cpuinfo.cpu_clock_freq; + + seq_printf(m, + "CPU:\t\tNios II/%s\n" + "REV:\t\t%i\n" + "MMU:\t\t%s\n" + "FPU:\t\tnone\n" + "Clocking:\t%u.%02u MHz\n" + "BogoMips:\t%lu.%02lu\n" + "Calibration:\t%lu loops\n", + cpuinfo.cpu_impl, + CONFIG_NIOS2_ARCH_REVISION, + cpuinfo.mmu ? "present" : "none", + clockfreq / 1000000, (clockfreq / 100000) % 10, + (loops_per_jiffy * HZ) / 500000, + ((loops_per_jiffy * HZ) / 5000) % 100, + (loops_per_jiffy * HZ)); + + seq_printf(m, + "HW:\n" + " MUL:\t\t%s\n" + " MULX:\t\t%s\n" + " DIV:\t\t%s\n" + " BMX:\t\t%s\n" + " CDX:\t\t%s\n", + cpuinfo.has_mul ? "yes" : "no", + cpuinfo.has_mulx ? "yes" : "no", + cpuinfo.has_div ? "yes" : "no", + cpuinfo.has_bmx ? "yes" : "no", + cpuinfo.has_cdx ? "yes" : "no"); + + seq_printf(m, + "Icache:\t\t%ukB, line length: %u\n", + cpuinfo.icache_size >> 10, + cpuinfo.icache_line_size); + + seq_printf(m, + "Dcache:\t\t%ukB, line length: %u\n", + cpuinfo.dcache_size >> 10, + cpuinfo.dcache_line_size); + + seq_printf(m, + "TLB:\t\t%u ways, %u entries, %u PID bits\n", + cpuinfo.tlb_num_ways, + cpuinfo.tlb_num_entries, + cpuinfo.tlb_pid_num_bits); + + return 0; +} + +static void *cpuinfo_start(struct seq_file *m, loff_t *pos) +{ + unsigned long i = *pos; + + return i < num_possible_cpus() ? (void *) (i + 1) : NULL; +} + +static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return cpuinfo_start(m, pos); +} + +static void cpuinfo_stop(struct seq_file *m, void *v) +{ +} + +const struct seq_operations cpuinfo_op = { + .start = cpuinfo_start, + .next = cpuinfo_next, + .stop = cpuinfo_stop, + .show = show_cpuinfo +}; + +#endif /* CONFIG_PROC_FS */ diff --git a/arch/nios2/kernel/entry.S b/arch/nios2/kernel/entry.S new file mode 100644 index 000000000..99f0a65e6 --- /dev/null +++ b/arch/nios2/kernel/entry.S @@ -0,0 +1,568 @@ +/* + * linux/arch/nios2/kernel/entry.S + * + * Copyright (C) 2013-2014 Altera Corporation + * Copyright (C) 2009, Wind River Systems Inc + * + * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com + * + * Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com) + * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, + * Kenneth Albanowski <kjahds@kjahds.com>, + * Copyright (C) 2000 Lineo Inc. (www.lineo.com) + * Copyright (C) 2004 Microtronix Datacom Ltd. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Linux/m68k support by Hamish Macdonald + * + * 68060 fixes by Jesper Skov + * ColdFire support by Greg Ungerer (gerg@snapgear.com) + * 5307 fixes by David W. Miller + * linux 2.4 support David McCullough <davidm@snapgear.com> + */ + +#include <linux/sys.h> +#include <linux/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/asm-macros.h> +#include <asm/thread_info.h> +#include <asm/errno.h> +#include <asm/setup.h> +#include <asm/entry.h> +#include <asm/unistd.h> +#include <asm/processor.h> + +.macro GET_THREAD_INFO reg +.if THREAD_SIZE & 0xffff0000 + andhi \reg, sp, %hi(~(THREAD_SIZE-1)) +.else + addi \reg, r0, %lo(~(THREAD_SIZE-1)) + and \reg, \reg, sp +.endif +.endm + +.macro kuser_cmpxchg_check + /* + * Make sure our user space atomic helper is restarted if it was + * interrupted in a critical region. + * ea-4 = address of interrupted insn (ea must be preserved). + * sp = saved regs. + * cmpxchg_ldw = first critical insn, cmpxchg_stw = last critical insn. + * If ea <= cmpxchg_stw and ea > cmpxchg_ldw then saved EA is set to + * cmpxchg_ldw + 4. + */ + /* et = cmpxchg_stw + 4 */ + movui et, (KUSER_BASE + 4 + (cmpxchg_stw - __kuser_helper_start)) + bgtu ea, et, 1f + + subi et, et, (cmpxchg_stw - cmpxchg_ldw) /* et = cmpxchg_ldw + 4 */ + bltu ea, et, 1f + stw et, PT_EA(sp) /* fix up EA */ + mov ea, et +1: +.endm + +.section .rodata +.align 4 +exception_table: + .word unhandled_exception /* 0 - Reset */ + .word unhandled_exception /* 1 - Processor-only Reset */ + .word external_interrupt /* 2 - Interrupt */ + .word handle_trap /* 3 - Trap Instruction */ + + .word instruction_trap /* 4 - Unimplemented instruction */ + .word handle_illegal /* 5 - Illegal instruction */ + .word handle_unaligned /* 6 - Misaligned data access */ + .word handle_unaligned /* 7 - Misaligned destination address */ + + .word handle_diverror /* 8 - Division error */ + .word protection_exception_ba /* 9 - Supervisor-only instr. address */ + .word protection_exception_instr /* 10 - Supervisor only instruction */ + .word protection_exception_ba /* 11 - Supervisor only data address */ + + .word unhandled_exception /* 12 - Double TLB miss (data) */ + .word protection_exception_pte /* 13 - TLB permission violation (x) */ + .word protection_exception_pte /* 14 - TLB permission violation (r) */ + .word protection_exception_pte /* 15 - TLB permission violation (w) */ + + .word unhandled_exception /* 16 - MPU region violation */ + +trap_table: + .word handle_system_call /* 0 */ + .word handle_trap_1 /* 1 */ + .word handle_trap_2 /* 2 */ + .word handle_trap_3 /* 3 */ + .word handle_trap_reserved /* 4 */ + .word handle_trap_reserved /* 5 */ + .word handle_trap_reserved /* 6 */ + .word handle_trap_reserved /* 7 */ + .word handle_trap_reserved /* 8 */ + .word handle_trap_reserved /* 9 */ + .word handle_trap_reserved /* 10 */ + .word handle_trap_reserved /* 11 */ + .word handle_trap_reserved /* 12 */ + .word handle_trap_reserved /* 13 */ + .word handle_trap_reserved /* 14 */ + .word handle_trap_reserved /* 15 */ + .word handle_trap_reserved /* 16 */ + .word handle_trap_reserved /* 17 */ + .word handle_trap_reserved /* 18 */ + .word handle_trap_reserved /* 19 */ + .word handle_trap_reserved /* 20 */ + .word handle_trap_reserved /* 21 */ + .word handle_trap_reserved /* 22 */ + .word handle_trap_reserved /* 23 */ + .word handle_trap_reserved /* 24 */ + .word handle_trap_reserved /* 25 */ + .word handle_trap_reserved /* 26 */ + .word handle_trap_reserved /* 27 */ + .word handle_trap_reserved /* 28 */ + .word handle_trap_reserved /* 29 */ +#ifdef CONFIG_KGDB + .word handle_kgdb_breakpoint /* 30 KGDB breakpoint */ +#else + .word instruction_trap /* 30 */ +#endif + .word handle_breakpoint /* 31 */ + +.text +.set noat +.set nobreak + +ENTRY(inthandler) + SAVE_ALL + + kuser_cmpxchg_check + + /* Clear EH bit before we get a new excpetion in the kernel + * and after we have saved it to the exception frame. This is done + * whether it's trap, tlb-miss or interrupt. If we don't do this + * estatus is not updated the next exception. + */ + rdctl r24, status + movi r9, %lo(~STATUS_EH) + and r24, r24, r9 + wrctl status, r24 + + /* Read cause and vector and branch to the associated handler */ + mov r4, sp + rdctl r5, exception + movia r9, exception_table + add r24, r9, r5 + ldw r24, 0(r24) + jmp r24 + + +/*********************************************************************** + * Handle traps + *********************************************************************** + */ +ENTRY(handle_trap) + ldwio r24, -4(ea) /* instruction that caused the exception */ + srli r24, r24, 4 + andi r24, r24, 0x7c + movia r9,trap_table + add r24, r24, r9 + ldw r24, 0(r24) + jmp r24 + + +/*********************************************************************** + * Handle system calls + *********************************************************************** + */ +ENTRY(handle_system_call) + /* Enable interrupts */ + rdctl r10, status + ori r10, r10, STATUS_PIE + wrctl status, r10 + + /* Reload registers destroyed by common code. */ + ldw r4, PT_R4(sp) + ldw r5, PT_R5(sp) + +local_restart: + stw r2, PT_ORIG_R2(sp) + /* Check that the requested system call is within limits */ + movui r1, __NR_syscalls + bgeu r2, r1, ret_invsyscall + slli r1, r2, 2 + movhi r11, %hiadj(sys_call_table) + add r1, r1, r11 + ldw r1, %lo(sys_call_table)(r1) + + /* Check if we are being traced */ + GET_THREAD_INFO r11 + ldw r11,TI_FLAGS(r11) + BTBNZ r11,r11,TIF_SYSCALL_TRACE,traced_system_call + + /* Execute the system call */ + callr r1 + + /* If the syscall returns a negative result: + * Set r7 to 1 to indicate error, + * Negate r2 to get a positive error code + * If the syscall returns zero or a positive value: + * Set r7 to 0. + * The sigreturn system calls will skip the code below by + * adding to register ra. To avoid destroying registers + */ +translate_rc_and_ret: + movi r1, 0 + bge r2, zero, 3f + ldw r1, PT_ORIG_R2(sp) + addi r1, r1, 1 + beq r1, zero, 3f + sub r2, zero, r2 + movi r1, 1 +3: + stw r2, PT_R2(sp) + stw r1, PT_R7(sp) +end_translate_rc_and_ret: + +ret_from_exception: + ldw r1, PT_ESTATUS(sp) + /* if so, skip resched, signals */ + TSTBNZ r1, r1, ESTATUS_EU, Luser_return + +restore_all: + rdctl r10, status /* disable intrs */ + andi r10, r10, %lo(~STATUS_PIE) + wrctl status, r10 + RESTORE_ALL + eret + + /* If the syscall number was invalid return ENOSYS */ +ret_invsyscall: + movi r2, -ENOSYS + br translate_rc_and_ret + + /* This implements the same as above, except it calls + * do_syscall_trace_enter and do_syscall_trace_exit before and after the + * syscall in order for utilities like strace and gdb to work. + */ +traced_system_call: + SAVE_SWITCH_STACK + call do_syscall_trace_enter + RESTORE_SWITCH_STACK + + /* Create system call register arguments. The 5th and 6th + arguments on stack are already in place at the beginning + of pt_regs. */ + ldw r2, PT_R2(sp) + ldw r4, PT_R4(sp) + ldw r5, PT_R5(sp) + ldw r6, PT_R6(sp) + ldw r7, PT_R7(sp) + + /* Fetch the syscall function. */ + movui r1, __NR_syscalls + bgeu r2, r1, traced_invsyscall + slli r1, r2, 2 + movhi r11,%hiadj(sys_call_table) + add r1, r1, r11 + ldw r1, %lo(sys_call_table)(r1) + + callr r1 + + /* If the syscall returns a negative result: + * Set r7 to 1 to indicate error, + * Negate r2 to get a positive error code + * If the syscall returns zero or a positive value: + * Set r7 to 0. + * The sigreturn system calls will skip the code below by + * adding to register ra. To avoid destroying registers + */ +translate_rc_and_ret2: + movi r1, 0 + bge r2, zero, 4f + ldw r1, PT_ORIG_R2(sp) + addi r1, r1, 1 + beq r1, zero, 4f + sub r2, zero, r2 + movi r1, 1 +4: + stw r2, PT_R2(sp) + stw r1, PT_R7(sp) +end_translate_rc_and_ret2: + SAVE_SWITCH_STACK + call do_syscall_trace_exit + RESTORE_SWITCH_STACK + br ret_from_exception + + /* If the syscall number was invalid return ENOSYS */ +traced_invsyscall: + movi r2, -ENOSYS + br translate_rc_and_ret2 + +Luser_return: + GET_THREAD_INFO r11 /* get thread_info pointer */ + ldw r10, TI_FLAGS(r11) /* get thread_info->flags */ + ANDI32 r11, r10, _TIF_WORK_MASK + beq r11, r0, restore_all /* Nothing to do */ + BTBZ r1, r10, TIF_NEED_RESCHED, Lsignal_return + + /* Reschedule work */ + call schedule + br ret_from_exception + +Lsignal_return: + ANDI32 r1, r10, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME + beq r1, r0, restore_all + mov r4, sp /* pt_regs */ + SAVE_SWITCH_STACK + call do_notify_resume + beq r2, r0, no_work_pending + RESTORE_SWITCH_STACK + /* prepare restart syscall here without leaving kernel */ + ldw r2, PT_R2(sp) /* reload syscall number in r2 */ + ldw r4, PT_R4(sp) /* reload syscall arguments r4-r9 */ + ldw r5, PT_R5(sp) + ldw r6, PT_R6(sp) + ldw r7, PT_R7(sp) + ldw r8, PT_R8(sp) + ldw r9, PT_R9(sp) + br local_restart /* restart syscall */ + +no_work_pending: + RESTORE_SWITCH_STACK + br ret_from_exception + +/*********************************************************************** + * Handle external interrupts. + *********************************************************************** + */ +/* + * This is the generic interrupt handler (for all hardware interrupt + * sources). It figures out the vector number and calls the appropriate + * interrupt service routine directly. + */ +external_interrupt: + rdctl r12, ipending + rdctl r9, ienable + and r12, r12, r9 + /* skip if no interrupt is pending */ + beq r12, r0, ret_from_interrupt + + /* + * Process an external hardware interrupt. + */ + + addi ea, ea, -4 /* re-issue the interrupted instruction */ + stw ea, PT_EA(sp) +2: movi r4, %lo(-1) /* Start from bit position 0, + highest priority */ + /* This is the IRQ # for handler call */ +1: andi r10, r12, 1 /* Isolate bit we are interested in */ + srli r12, r12, 1 /* shift count is costly without hardware + multiplier */ + addi r4, r4, 1 + beq r10, r0, 1b + mov r5, sp /* Setup pt_regs pointer for handler call */ + call do_IRQ + rdctl r12, ipending /* check again if irq still pending */ + rdctl r9, ienable /* Isolate possible interrupts */ + and r12, r12, r9 + bne r12, r0, 2b + /* br ret_from_interrupt */ /* fall through to ret_from_interrupt */ + +ENTRY(ret_from_interrupt) + ldw r1, PT_ESTATUS(sp) /* check if returning to kernel */ + TSTBNZ r1, r1, ESTATUS_EU, Luser_return + +#ifdef CONFIG_PREEMPTION + GET_THREAD_INFO r1 + ldw r4, TI_PREEMPT_COUNT(r1) + bne r4, r0, restore_all + ldw r4, TI_FLAGS(r1) /* ? Need resched set */ + BTBZ r10, r4, TIF_NEED_RESCHED, restore_all + ldw r4, PT_ESTATUS(sp) /* ? Interrupts off */ + andi r10, r4, ESTATUS_EPIE + beq r10, r0, restore_all + call preempt_schedule_irq +#endif + br restore_all + +/*********************************************************************** + * A few syscall wrappers + *********************************************************************** + */ +/* + * int clone(unsigned long clone_flags, unsigned long newsp, + * int __user * parent_tidptr, int __user * child_tidptr, + * int tls_val) + */ +ENTRY(sys_clone) + SAVE_SWITCH_STACK + subi sp, sp, 4 /* make space for tls pointer */ + stw r8, 0(sp) /* pass tls pointer (r8) via stack (5th argument) */ + call nios2_clone + addi sp, sp, 4 + RESTORE_SWITCH_STACK + ret + +ENTRY(sys_rt_sigreturn) + SAVE_SWITCH_STACK + mov r4, sp + call do_rt_sigreturn + RESTORE_SWITCH_STACK + addi ra, ra, (end_translate_rc_and_ret - translate_rc_and_ret) + ret + +/*********************************************************************** + * A few other wrappers and stubs + *********************************************************************** + */ +protection_exception_pte: + rdctl r6, pteaddr + slli r6, r6, 10 + call do_page_fault + br ret_from_exception + +protection_exception_ba: + rdctl r6, badaddr + call do_page_fault + br ret_from_exception + +protection_exception_instr: + call handle_supervisor_instr + br ret_from_exception + +handle_breakpoint: + call breakpoint_c + br ret_from_exception + +#ifdef CONFIG_NIOS2_ALIGNMENT_TRAP +handle_unaligned: + SAVE_SWITCH_STACK + call handle_unaligned_c + RESTORE_SWITCH_STACK + br ret_from_exception +#else +handle_unaligned: + call handle_unaligned_c + br ret_from_exception +#endif + +handle_illegal: + call handle_illegal_c + br ret_from_exception + +handle_diverror: + call handle_diverror_c + br ret_from_exception + +#ifdef CONFIG_KGDB +handle_kgdb_breakpoint: + call kgdb_breakpoint_c + br ret_from_exception +#endif + +handle_trap_1: + call handle_trap_1_c + br ret_from_exception + +handle_trap_2: + call handle_trap_2_c + br ret_from_exception + +handle_trap_3: +handle_trap_reserved: + call handle_trap_3_c + br ret_from_exception + +/* + * Beware - when entering resume, prev (the current task) is + * in r4, next (the new task) is in r5, don't change these + * registers. + */ +ENTRY(resume) + + rdctl r7, status /* save thread status reg */ + stw r7, TASK_THREAD + THREAD_KPSR(r4) + + andi r7, r7, %lo(~STATUS_PIE) /* disable interrupts */ + wrctl status, r7 + + SAVE_SWITCH_STACK + stw sp, TASK_THREAD + THREAD_KSP(r4)/* save kernel stack pointer */ + ldw sp, TASK_THREAD + THREAD_KSP(r5)/* restore new thread stack */ + movia r24, _current_thread /* save thread */ + GET_THREAD_INFO r1 + stw r1, 0(r24) + RESTORE_SWITCH_STACK + + ldw r7, TASK_THREAD + THREAD_KPSR(r5)/* restore thread status reg */ + wrctl status, r7 + ret + +ENTRY(ret_from_fork) + call schedule_tail + br ret_from_exception + +ENTRY(ret_from_kernel_thread) + call schedule_tail + mov r4,r17 /* arg */ + callr r16 /* function */ + br ret_from_exception + +/* + * Kernel user helpers. + * + * Each segment is 64-byte aligned and will be mapped to the <User space>. + * New segments (if ever needed) must be added after the existing ones. + * This mechanism should be used only for things that are really small and + * justified, and not be abused freely. + * + */ + + /* Filling pads with undefined instructions. */ +.macro kuser_pad sym size + .if ((. - \sym) & 3) + .rept (4 - (. - \sym) & 3) + .byte 0 + .endr + .endif + .rept ((\size - (. - \sym)) / 4) + .word 0xdeadbeef + .endr +.endm + + .align 6 + .globl __kuser_helper_start +__kuser_helper_start: + +__kuser_helper_version: /* @ 0x1000 */ + .word ((__kuser_helper_end - __kuser_helper_start) >> 6) + +__kuser_cmpxchg: /* @ 0x1004 */ + /* + * r4 pointer to exchange variable + * r5 old value + * r6 new value + */ +cmpxchg_ldw: + ldw r2, 0(r4) /* load current value */ + sub r2, r2, r5 /* compare with old value */ + bne r2, zero, cmpxchg_ret + + /* We had a match, store the new value */ +cmpxchg_stw: + stw r6, 0(r4) +cmpxchg_ret: + ret + + kuser_pad __kuser_cmpxchg, 64 + + .globl __kuser_sigtramp +__kuser_sigtramp: + movi r2, __NR_rt_sigreturn + trap + + kuser_pad __kuser_sigtramp, 64 + + .globl __kuser_helper_end +__kuser_helper_end: diff --git a/arch/nios2/kernel/head.S b/arch/nios2/kernel/head.S new file mode 100644 index 000000000..372ce4a33 --- /dev/null +++ b/arch/nios2/kernel/head.S @@ -0,0 +1,175 @@ +/* + * Copyright (C) 2009 Wind River Systems Inc + * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com + * Copyright (C) 2004 Microtronix Datacom Ltd + * Copyright (C) 2001 Vic Phillips, Microtronix Datacom Ltd. + * + * Based on head.S for Altera's Excalibur development board with nios processor + * + * Based on the following from the Excalibur sdk distribution: + * NA_MemoryMap.s, NR_JumpToStart.s, NR_Setup.s, NR_CWPManager.s + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/thread_info.h> +#include <asm/processor.h> +#include <asm/cache.h> +#include <asm/page.h> +#include <asm/asm-offsets.h> +#include <asm/asm-macros.h> + +/* + * ZERO_PAGE is a special page that is used for zero-initialized + * data and COW. + */ +.data +.global empty_zero_page +.align 12 +empty_zero_page: + .space PAGE_SIZE + +/* + * This global variable is used as an extension to the nios' + * STATUS register to emulate a user/supervisor mode. + */ + .data + .align 2 + .set noat + + .global _current_thread +_current_thread: + .long 0 +/* + * Input(s): passed from u-boot + * r4 - Optional pointer to a board information structure. + * r5 - Optional pointer to the physical starting address of the init RAM + * disk. + * r6 - Optional pointer to the physical ending address of the init RAM + * disk. + * r7 - Optional pointer to the physical starting address of any kernel + * command-line parameters. + */ + +/* + * First executable code - detected and jumped to by the ROM bootstrap + * if the code resides in flash (looks for "Nios" at offset 0x0c from + * the potential executable image). + */ + __HEAD +ENTRY(_start) + wrctl status, r0 /* Disable interrupts */ + + /* Initialize all cache lines within the instruction cache */ + movia r1, NIOS2_ICACHE_SIZE + movui r2, NIOS2_ICACHE_LINE_SIZE + +icache_init: + initi r1 + sub r1, r1, r2 + bgt r1, r0, icache_init + br 1f + + /* + * This is the default location for the exception handler. Code in jump + * to our handler + */ +ENTRY(exception_handler_hook) + movia r24, inthandler + jmp r24 + +ENTRY(fast_handler) + nextpc et +helper: + stw r3, r3save - helper(et) + + rdctl r3 , pteaddr + srli r3, r3, 12 + slli r3, r3, 2 + movia et, pgd_current + + ldw et, 0(et) + add r3, et, r3 + ldw et, 0(r3) + + rdctl r3, pteaddr + andi r3, r3, 0xfff + add et, r3, et + ldw et, 0(et) + wrctl tlbacc, et + nextpc et +helper2: + ldw r3, r3save - helper2(et) + subi ea, ea, 4 + eret +r3save: + .word 0x0 +ENTRY(fast_handler_end) + +1: + /* + * After the instruction cache is initialized, the data cache must + * also be initialized. + */ + movia r1, NIOS2_DCACHE_SIZE + movui r2, NIOS2_DCACHE_LINE_SIZE + +dcache_init: + initd 0(r1) + sub r1, r1, r2 + bgt r1, r0, dcache_init + + nextpc r1 /* Find out where we are */ +chkadr: + movia r2, chkadr + beq r1, r2,finish_move /* We are running in RAM done */ + addi r1, r1,(_start - chkadr) /* Source */ + movia r2, _start /* Destination */ + movia r3, __bss_start /* End of copy */ + +loop_move: /* r1: src, r2: dest, r3: last dest */ + ldw r8, 0(r1) /* load a word from [r1] */ + stw r8, 0(r2) /* store a word to dest [r2] */ + flushd 0(r2) /* Flush cache for safety */ + addi r1, r1, 4 /* inc the src addr */ + addi r2, r2, 4 /* inc the dest addr */ + blt r2, r3, loop_move + + movia r1, finish_move /* VMA(_start)->l1 */ + jmp r1 /* jmp to _start */ + +finish_move: + + /* Mask off all possible interrupts */ + wrctl ienable, r0 + + /* Clear .bss */ + movia r2, __bss_start + movia r1, __bss_stop +1: + stb r0, 0(r2) + addi r2, r2, 1 + bne r1, r2, 1b + + movia r1, init_thread_union /* set stack at top of the task union */ + addi sp, r1, THREAD_SIZE + movia r2, _current_thread /* Remember current thread */ + stw r1, 0(r2) + + movia r1, nios2_boot_init /* save args r4-r7 passed from u-boot */ + callr r1 + + movia r1, start_kernel /* call start_kernel as a subroutine */ + callr r1 + + /* If we return from start_kernel, break to the oci debugger and + * buggered we are. + */ + break + + /* End of startup code */ +.set at diff --git a/arch/nios2/kernel/insnemu.S b/arch/nios2/kernel/insnemu.S new file mode 100644 index 000000000..a027cc68b --- /dev/null +++ b/arch/nios2/kernel/insnemu.S @@ -0,0 +1,580 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2003-2013 Altera Corporation + * All rights reserved. + */ + + +#include <linux/linkage.h> +#include <asm/entry.h> + +.set noat +.set nobreak + +/* +* Explicitly allow the use of r1 (the assembler temporary register) +* within this code. This register is normally reserved for the use of +* the compiler. +*/ + +ENTRY(instruction_trap) + ldw r1, PT_R1(sp) // Restore registers + ldw r2, PT_R2(sp) + ldw r3, PT_R3(sp) + ldw r4, PT_R4(sp) + ldw r5, PT_R5(sp) + ldw r6, PT_R6(sp) + ldw r7, PT_R7(sp) + ldw r8, PT_R8(sp) + ldw r9, PT_R9(sp) + ldw r10, PT_R10(sp) + ldw r11, PT_R11(sp) + ldw r12, PT_R12(sp) + ldw r13, PT_R13(sp) + ldw r14, PT_R14(sp) + ldw r15, PT_R15(sp) + ldw ra, PT_RA(sp) + ldw fp, PT_FP(sp) + ldw gp, PT_GP(sp) + ldw et, PT_ESTATUS(sp) + wrctl estatus, et + ldw ea, PT_EA(sp) + ldw et, PT_SP(sp) /* backup sp in et */ + + addi sp, sp, PT_REGS_SIZE + + /* INSTRUCTION EMULATION + * --------------------- + * + * Nios II processors generate exceptions for unimplemented instructions. + * The routines below emulate these instructions. Depending on the + * processor core, the only instructions that might need to be emulated + * are div, divu, mul, muli, mulxss, mulxsu, and mulxuu. + * + * The emulations match the instructions, except for the following + * limitations: + * + * 1) The emulation routines do not emulate the use of the exception + * temporary register (et) as a source operand because the exception + * handler already has modified it. + * + * 2) The routines do not emulate the use of the stack pointer (sp) or + * the exception return address register (ea) as a destination because + * modifying these registers crashes the exception handler or the + * interrupted routine. + * + * Detailed Design + * --------------- + * + * The emulation routines expect the contents of integer registers r0-r31 + * to be on the stack at addresses sp, 4(sp), 8(sp), ... 124(sp). The + * routines retrieve source operands from the stack and modify the + * destination register's value on the stack prior to the end of the + * exception handler. Then all registers except the destination register + * are restored to their previous values. + * + * The instruction that causes the exception is found at address -4(ea). + * The instruction's OP and OPX fields identify the operation to be + * performed. + * + * One instruction, muli, is an I-type instruction that is identified by + * an OP field of 0x24. + * + * muli AAAAA,BBBBB,IIIIIIIIIIIIIIII,-0x24- + * 27 22 6 0 <-- LSB of field + * + * The remaining emulated instructions are R-type and have an OP field + * of 0x3a. Their OPX fields identify them. + * + * R-type AAAAA,BBBBB,CCCCC,XXXXXX,NNNNN,-0x3a- + * 27 22 17 11 6 0 <-- LSB of field + * + * + * Opcode Encoding. muli is identified by its OP value. Then OPX & 0x02 + * is used to differentiate between the division opcodes and the + * remaining multiplication opcodes. + * + * Instruction OP OPX OPX & 0x02 + * ----------- ---- ---- ---------- + * muli 0x24 + * divu 0x3a 0x24 0 + * div 0x3a 0x25 0 + * mul 0x3a 0x27 != 0 + * mulxuu 0x3a 0x07 != 0 + * mulxsu 0x3a 0x17 != 0 + * mulxss 0x3a 0x1f != 0 + */ + + + /* + * Save everything on the stack to make it easy for the emulation + * routines to retrieve the source register operands. + */ + + addi sp, sp, -128 + stw zero, 0(sp) /* Save zero on stack to avoid special case for r0. */ + stw r1, 4(sp) + stw r2, 8(sp) + stw r3, 12(sp) + stw r4, 16(sp) + stw r5, 20(sp) + stw r6, 24(sp) + stw r7, 28(sp) + stw r8, 32(sp) + stw r9, 36(sp) + stw r10, 40(sp) + stw r11, 44(sp) + stw r12, 48(sp) + stw r13, 52(sp) + stw r14, 56(sp) + stw r15, 60(sp) + stw r16, 64(sp) + stw r17, 68(sp) + stw r18, 72(sp) + stw r19, 76(sp) + stw r20, 80(sp) + stw r21, 84(sp) + stw r22, 88(sp) + stw r23, 92(sp) + /* Don't bother to save et. It's already been changed. */ + rdctl r5, estatus + stw r5, 100(sp) + + stw gp, 104(sp) + stw et, 108(sp) /* et contains previous sp value. */ + stw fp, 112(sp) + stw ea, 116(sp) + stw ra, 120(sp) + + + /* + * Split the instruction into its fields. We need 4*A, 4*B, and 4*C as + * offsets to the stack pointer for access to the stored register values. + */ + ldw r2,-4(ea) /* r2 = AAAAA,BBBBB,IIIIIIIIIIIIIIII,PPPPPP */ + roli r3, r2, 7 /* r3 = BBB,IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BB */ + roli r4, r3, 3 /* r4 = IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB */ + roli r5, r4, 2 /* r5 = IIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB,II */ + srai r4, r4, 16 /* r4 = (sign-extended) IMM16 */ + roli r6, r5, 5 /* r6 = XXXX,NNNNN,PPPPPP,AAAAA,BBBBB,CCCCC,XX */ + andi r2, r2, 0x3f /* r2 = 00000000000000000000000000,PPPPPP */ + andi r3, r3, 0x7c /* r3 = 0000000000000000000000000,AAAAA,00 */ + andi r5, r5, 0x7c /* r5 = 0000000000000000000000000,BBBBB,00 */ + andi r6, r6, 0x7c /* r6 = 0000000000000000000000000,CCCCC,00 */ + + /* Now + * r2 = OP + * r3 = 4*A + * r4 = IMM16 (sign extended) + * r5 = 4*B + * r6 = 4*C + */ + + /* + * Get the operands. + * + * It is necessary to check for muli because it uses an I-type + * instruction format, while the other instructions are have an R-type + * format. + * + * Prepare for either multiplication or division loop. + * They both loop 32 times. + */ + movi r14, 32 + + add r3, r3, sp /* r3 = address of A-operand. */ + ldw r3, 0(r3) /* r3 = A-operand. */ + movi r7, 0x24 /* muli opcode (I-type instruction format) */ + beq r2, r7, mul_immed /* muli doesn't use the B register as a source */ + + add r5, r5, sp /* r5 = address of B-operand. */ + ldw r5, 0(r5) /* r5 = B-operand. */ + /* r4 = SSSSSSSSSSSSSSSS,-----IMM16------ */ + /* IMM16 not needed, align OPX portion */ + /* r4 = SSSSSSSSSSSSSSSS,CCCCC,-OPX--,00000 */ + srli r4, r4, 5 /* r4 = 00000,SSSSSSSSSSSSSSSS,CCCCC,-OPX-- */ + andi r4, r4, 0x3f /* r4 = 00000000000000000000000000,-OPX-- */ + + /* Now + * r2 = OP + * r3 = src1 + * r5 = src2 + * r4 = OPX (no longer can be muli) + * r6 = 4*C + */ + + + /* + * Multiply or Divide? + */ + andi r7, r4, 0x02 /* For R-type multiply instructions, + OPX & 0x02 != 0 */ + bne r7, zero, multiply + + + /* DIVISION + * + * Divide an unsigned dividend by an unsigned divisor using + * a shift-and-subtract algorithm. The example below shows + * 43 div 7 = 6 for 8-bit integers. This classic algorithm uses a + * single register to store both the dividend and the quotient, + * allowing both values to be shifted with a single instruction. + * + * remainder dividend:quotient + * --------- ----------------- + * initialize 00000000 00101011: + * shift 00000000 0101011:_ + * remainder >= divisor? no 00000000 0101011:0 + * shift 00000000 101011:0_ + * remainder >= divisor? no 00000000 101011:00 + * shift 00000001 01011:00_ + * remainder >= divisor? no 00000001 01011:000 + * shift 00000010 1011:000_ + * remainder >= divisor? no 00000010 1011:0000 + * shift 00000101 011:0000_ + * remainder >= divisor? no 00000101 011:00000 + * shift 00001010 11:00000_ + * remainder >= divisor? yes 00001010 11:000001 + * remainder -= divisor - 00000111 + * ---------- + * 00000011 11:000001 + * shift 00000111 1:000001_ + * remainder >= divisor? yes 00000111 1:0000011 + * remainder -= divisor - 00000111 + * ---------- + * 00000000 1:0000011 + * shift 00000001 :0000011_ + * remainder >= divisor? no 00000001 :00000110 + * + * The quotient is 00000110. + */ + +divide: + /* + * Prepare for division by assuming the result + * is unsigned, and storing its "sign" as 0. + */ + movi r17, 0 + + + /* Which division opcode? */ + xori r7, r4, 0x25 /* OPX of div */ + bne r7, zero, unsigned_division + + + /* + * OPX is div. Determine and store the sign of the quotient. + * Then take the absolute value of both operands. + */ + xor r17, r3, r5 /* MSB contains sign of quotient */ + bge r3,zero,dividend_is_nonnegative + sub r3, zero, r3 /* -r3 */ +dividend_is_nonnegative: + bge r5, zero, divisor_is_nonnegative + sub r5, zero, r5 /* -r5 */ +divisor_is_nonnegative: + + +unsigned_division: + /* Initialize the unsigned-division loop. */ + movi r13, 0 /* remainder = 0 */ + + /* Now + * r3 = dividend : quotient + * r4 = 0x25 for div, 0x24 for divu + * r5 = divisor + * r13 = remainder + * r14 = loop counter (already initialized to 32) + * r17 = MSB contains sign of quotient + */ + + + /* + * for (count = 32; count > 0; --count) + * { + */ +divide_loop: + + /* + * Division: + * + * (remainder:dividend:quotient) <<= 1; + */ + slli r13, r13, 1 + cmplt r7, r3, zero /* r7 = MSB of r3 */ + or r13, r13, r7 + slli r3, r3, 1 + + + /* + * if (remainder >= divisor) + * { + * set LSB of quotient + * remainder -= divisor; + * } + */ + bltu r13, r5, div_skip + ori r3, r3, 1 + sub r13, r13, r5 +div_skip: + + /* + * } + */ + subi r14, r14, 1 + bne r14, zero, divide_loop + + + /* Now + * r3 = quotient + * r4 = 0x25 for div, 0x24 for divu + * r6 = 4*C + * r17 = MSB contains sign of quotient + */ + + + /* + * Conditionally negate signed quotient. If quotient is unsigned, + * the sign already is initialized to 0. + */ + bge r17, zero, quotient_is_nonnegative + sub r3, zero, r3 /* -r3 */ + quotient_is_nonnegative: + + + /* + * Final quotient is in r3. + */ + add r6, r6, sp + stw r3, 0(r6) /* write quotient to stack */ + br restore_registers + + + + + /* MULTIPLICATION + * + * A "product" is the number that one gets by summing a "multiplicand" + * several times. The "multiplier" specifies the number of copies of the + * multiplicand that are summed. + * + * Actual multiplication algorithms don't use repeated addition, however. + * Shift-and-add algorithms get the same answer as repeated addition, and + * they are faster. To compute the lower half of a product (pppp below) + * one shifts the product left before adding in each of the partial + * products (a * mmmm) through (d * mmmm). + * + * To compute the upper half of a product (PPPP below), one adds in the + * partial products (d * mmmm) through (a * mmmm), each time following + * the add by a right shift of the product. + * + * mmmm + * * abcd + * ------ + * #### = d * mmmm + * #### = c * mmmm + * #### = b * mmmm + * #### = a * mmmm + * -------- + * PPPPpppp + * + * The example above shows 4 partial products. Computing actual Nios II + * products requires 32 partials. + * + * It is possible to compute the result of mulxsu from the result of + * mulxuu because the only difference between the results of these two + * opcodes is the value of the partial product associated with the sign + * bit of rA. + * + * mulxsu = mulxuu - (rA < 0) ? rB : 0; + * + * It is possible to compute the result of mulxss from the result of + * mulxsu because the only difference between the results of these two + * opcodes is the value of the partial product associated with the sign + * bit of rB. + * + * mulxss = mulxsu - (rB < 0) ? rA : 0; + * + */ + +mul_immed: + /* Opcode is muli. Change it into mul for remainder of algorithm. */ + mov r6, r5 /* Field B is dest register, not field C. */ + mov r5, r4 /* Field IMM16 is src2, not field B. */ + movi r4, 0x27 /* OPX of mul is 0x27 */ + +multiply: + /* Initialize the multiplication loop. */ + movi r9, 0 /* mul_product = 0 */ + movi r10, 0 /* mulxuu_product = 0 */ + mov r11, r5 /* save original multiplier for mulxsu and mulxss */ + mov r12, r5 /* mulxuu_multiplier (will be shifted) */ + movi r16, 1 /* used to create "rori B,A,1" from "ror B,A,r16" */ + + /* Now + * r3 = multiplicand + * r5 = mul_multiplier + * r6 = 4 * dest_register (used later as offset to sp) + * r7 = temp + * r9 = mul_product + * r10 = mulxuu_product + * r11 = original multiplier + * r12 = mulxuu_multiplier + * r14 = loop counter (already initialized) + * r16 = 1 + */ + + + /* + * for (count = 32; count > 0; --count) + * { + */ +multiply_loop: + + /* + * mul_product <<= 1; + * lsb = multiplier & 1; + */ + slli r9, r9, 1 + andi r7, r12, 1 + + /* + * if (lsb == 1) + * { + * mulxuu_product += multiplicand; + * } + */ + beq r7, zero, mulx_skip + add r10, r10, r3 + cmpltu r7, r10, r3 /* Save the carry from the MSB of mulxuu_product. */ + ror r7, r7, r16 /* r7 = 0x80000000 on carry, or else 0x00000000 */ +mulx_skip: + + /* + * if (MSB of mul_multiplier == 1) + * { + * mul_product += multiplicand; + * } + */ + bge r5, zero, mul_skip + add r9, r9, r3 +mul_skip: + + /* + * mulxuu_product >>= 1; logical shift + * mul_multiplier <<= 1; done with MSB + * mulx_multiplier >>= 1; done with LSB + */ + srli r10, r10, 1 + or r10, r10, r7 /* OR in the saved carry bit. */ + slli r5, r5, 1 + srli r12, r12, 1 + + + /* + * } + */ + subi r14, r14, 1 + bne r14, zero, multiply_loop + + + /* + * Multiply emulation loop done. + */ + + /* Now + * r3 = multiplicand + * r4 = OPX + * r6 = 4 * dest_register (used later as offset to sp) + * r7 = temp + * r9 = mul_product + * r10 = mulxuu_product + * r11 = original multiplier + */ + + + /* Calculate address for result from 4 * dest_register */ + add r6, r6, sp + + + /* + * Select/compute the result based on OPX. + */ + + + /* OPX == mul? Then store. */ + xori r7, r4, 0x27 + beq r7, zero, store_product + + /* It's one of the mulx.. opcodes. Move over the result. */ + mov r9, r10 + + /* OPX == mulxuu? Then store. */ + xori r7, r4, 0x07 + beq r7, zero, store_product + + /* Compute mulxsu + * + * mulxsu = mulxuu - (rA < 0) ? rB : 0; + */ + bge r3, zero, mulxsu_skip + sub r9, r9, r11 +mulxsu_skip: + + /* OPX == mulxsu? Then store. */ + xori r7, r4, 0x17 + beq r7, zero, store_product + + /* Compute mulxss + * + * mulxss = mulxsu - (rB < 0) ? rA : 0; + */ + bge r11,zero,mulxss_skip + sub r9, r9, r3 +mulxss_skip: + /* At this point, assume that OPX is mulxss, so store*/ + + +store_product: + stw r9, 0(r6) + + +restore_registers: + /* No need to restore r0. */ + ldw r5, 100(sp) + wrctl estatus, r5 + + ldw r1, 4(sp) + ldw r2, 8(sp) + ldw r3, 12(sp) + ldw r4, 16(sp) + ldw r5, 20(sp) + ldw r6, 24(sp) + ldw r7, 28(sp) + ldw r8, 32(sp) + ldw r9, 36(sp) + ldw r10, 40(sp) + ldw r11, 44(sp) + ldw r12, 48(sp) + ldw r13, 52(sp) + ldw r14, 56(sp) + ldw r15, 60(sp) + ldw r16, 64(sp) + ldw r17, 68(sp) + ldw r18, 72(sp) + ldw r19, 76(sp) + ldw r20, 80(sp) + ldw r21, 84(sp) + ldw r22, 88(sp) + ldw r23, 92(sp) + /* Does not need to restore et */ + ldw gp, 104(sp) + + ldw fp, 112(sp) + ldw ea, 116(sp) + ldw ra, 120(sp) + ldw sp, 108(sp) /* last restore sp */ + eret + +.set at +.set break diff --git a/arch/nios2/kernel/irq.c b/arch/nios2/kernel/irq.c new file mode 100644 index 000000000..6b7890e5f --- /dev/null +++ b/arch/nios2/kernel/irq.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2013 Altera Corporation + * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw> + * + * based on irq.c from m68k which is: + * + * Copyright (C) 2007 Greg Ungerer <gerg@snapgear.com> + */ + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/of.h> + +static u32 ienable; + +asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs) +{ + struct pt_regs *oldregs = set_irq_regs(regs); + + irq_enter(); + generic_handle_domain_irq(NULL, hwirq); + irq_exit(); + + set_irq_regs(oldregs); +} + +static void chip_unmask(struct irq_data *d) +{ + ienable |= (1 << d->hwirq); + WRCTL(CTL_IENABLE, ienable); +} + +static void chip_mask(struct irq_data *d) +{ + ienable &= ~(1 << d->hwirq); + WRCTL(CTL_IENABLE, ienable); +} + +static struct irq_chip m_irq_chip = { + .name = "NIOS2-INTC", + .irq_unmask = chip_unmask, + .irq_mask = chip_mask, +}; + +static int irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw_irq_num) +{ + irq_set_chip_and_handler(virq, &m_irq_chip, handle_level_irq); + + return 0; +} + +static const struct irq_domain_ops irq_ops = { + .map = irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +void __init init_IRQ(void) +{ + struct irq_domain *domain; + struct device_node *node; + + node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.0"); + if (!node) + node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.1"); + + BUG_ON(!node); + + domain = irq_domain_add_linear(node, NIOS2_CPU_NR_IRQS, &irq_ops, NULL); + BUG_ON(!domain); + + irq_set_default_host(domain); + of_node_put(node); + /* Load the initial ienable value */ + ienable = RDCTL(CTL_IENABLE); +} diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c new file mode 100644 index 000000000..d0963fcb1 --- /dev/null +++ b/arch/nios2/kernel/kgdb.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Nios2 KGDB support + * + * Copyright (C) 2015 Altera Corporation + * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch> + * + * Based on the code posted by Kazuyasu on the Altera Forum at: + * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20 + */ +#include <linux/ptrace.h> +#include <linux/kgdb.h> +#include <linux/kdebug.h> +#include <linux/io.h> + +static int wait_for_remote_debugger; + +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = +{ + { "zero", GDB_SIZEOF_REG, -1 }, + { "at", GDB_SIZEOF_REG, offsetof(struct pt_regs, r1) }, + { "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r2) }, + { "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r3) }, + { "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r4) }, + { "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r5) }, + { "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r6) }, + { "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r7) }, + { "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r8) }, + { "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r9) }, + { "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, r10) }, + { "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, r11) }, + { "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, r12) }, + { "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, r13) }, + { "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, r14) }, + { "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, r15) }, + { "r16", GDB_SIZEOF_REG, -1 }, + { "r17", GDB_SIZEOF_REG, -1 }, + { "r18", GDB_SIZEOF_REG, -1 }, + { "r19", GDB_SIZEOF_REG, -1 }, + { "r20", GDB_SIZEOF_REG, -1 }, + { "r21", GDB_SIZEOF_REG, -1 }, + { "r22", GDB_SIZEOF_REG, -1 }, + { "r23", GDB_SIZEOF_REG, -1 }, + { "et", GDB_SIZEOF_REG, -1 }, + { "bt", GDB_SIZEOF_REG, -1 }, + { "gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp) }, + { "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) }, + { "fp", GDB_SIZEOF_REG, offsetof(struct pt_regs, fp) }, + { "ea", GDB_SIZEOF_REG, -1 }, + { "ba", GDB_SIZEOF_REG, -1 }, + { "ra", GDB_SIZEOF_REG, offsetof(struct pt_regs, ra) }, + { "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, ea) }, + { "status", GDB_SIZEOF_REG, -1 }, + { "estatus", GDB_SIZEOF_REG, offsetof(struct pt_regs, estatus) }, + { "bstatus", GDB_SIZEOF_REG, -1 }, + { "ienable", GDB_SIZEOF_REG, -1 }, + { "ipending", GDB_SIZEOF_REG, -1}, + { "cpuid", GDB_SIZEOF_REG, -1 }, + { "ctl6", GDB_SIZEOF_REG, -1 }, + { "exception", GDB_SIZEOF_REG, -1 }, + { "pteaddr", GDB_SIZEOF_REG, -1 }, + { "tlbacc", GDB_SIZEOF_REG, -1 }, + { "tlbmisc", GDB_SIZEOF_REG, -1 }, + { "eccinj", GDB_SIZEOF_REG, -1 }, + { "badaddr", GDB_SIZEOF_REG, -1 }, + { "config", GDB_SIZEOF_REG, -1 }, + { "mpubase", GDB_SIZEOF_REG, -1 }, + { "mpuacc", GDB_SIZEOF_REG, -1 }, +}; + +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return NULL; + + if (dbg_reg_def[regno].offset != -1) + memcpy(mem, (void *)regs + dbg_reg_def[regno].offset, + dbg_reg_def[regno].size); + else + memset(mem, 0, dbg_reg_def[regno].size); + + return dbg_reg_def[regno].name; +} + +int dbg_set_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return -EINVAL; + + if (dbg_reg_def[regno].offset != -1) + memcpy((void *)regs + dbg_reg_def[regno].offset, mem, + dbg_reg_def[regno].size); + + return 0; +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) +{ + memset((char *)gdb_regs, 0, NUMREGBYTES); + gdb_regs[GDB_SP] = p->thread.kregs->sp; + gdb_regs[GDB_PC] = p->thread.kregs->ea; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) +{ + regs->ea = pc; +} + +int kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, char *remcom_out_buffer, + struct pt_regs *regs) +{ + char *ptr; + unsigned long addr; + + switch (remcom_in_buffer[0]) { + case 's': + case 'c': + /* handle the optional parameters */ + ptr = &remcom_in_buffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->ea = addr; + + return 0; + } + + return -1; /* this means that we do not want to exit from the handler */ +} + +asmlinkage void kgdb_breakpoint_c(struct pt_regs *regs) +{ + /* + * The breakpoint entry code has moved the PC on by 4 bytes, so we must + * move it back. This could be done on the host but we do it here + */ + if (!wait_for_remote_debugger) + regs->ea -= 4; + else /* pass the first trap 30 code */ + wait_for_remote_debugger = 0; + + kgdb_handle_exception(30, SIGTRAP, 0, regs); +} + +int kgdb_arch_init(void) +{ + wait_for_remote_debugger = 1; + return 0; +} + +void kgdb_arch_exit(void) +{ + /* Nothing to do */ +} + +const struct kgdb_arch arch_kgdb_ops = { + /* Breakpoint instruction: trap 30 */ + .gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 }, +}; diff --git a/arch/nios2/kernel/misaligned.c b/arch/nios2/kernel/misaligned.c new file mode 100644 index 000000000..23e0544e1 --- /dev/null +++ b/arch/nios2/kernel/misaligned.c @@ -0,0 +1,238 @@ +/* + * linux/arch/nios2/kernel/misaligned.c + * + * basic emulation for mis-aligned accesses on the NIOS II cpu + * modelled after the version for arm in arm/alignment.c + * + * Brad Parker <brad@heeltoe.com> + * Copyright (C) 2010 Ambient Corporation + * Copyright (c) 2010 Altera Corporation, San Jose, California, USA. + * Copyright (c) 2010 Arrow Electronics, Inc. + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of + * this archive for more details. + */ + +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/proc_fs.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <linux/seq_file.h> + +#include <asm/traps.h> +#include <asm/unaligned.h> + +/* instructions we emulate */ +#define INST_LDHU 0x0b +#define INST_STH 0x0d +#define INST_LDH 0x0f +#define INST_STW 0x15 +#define INST_LDW 0x17 + +static unsigned int ma_usermode; +#define UM_WARN 0x01 +#define UM_FIXUP 0x02 +#define UM_SIGNAL 0x04 +#define KM_WARN 0x08 + +/* see arch/nios2/include/asm/ptrace.h */ +static u8 sys_stack_frame_reg_offset[] = { + /* struct pt_regs */ + 8, 9, 10, 11, 12, 13, 14, 15, 1, 2, 3, 4, 5, 6, 7, 0, + /* struct switch_stack */ + 16, 17, 18, 19, 20, 21, 22, 23, 0, 0, 0, 0, 0, 0, 0, 0 +}; + +static int reg_offsets[32]; + +static inline u32 get_reg_val(struct pt_regs *fp, int reg) +{ + u8 *p = ((u8 *)fp) + reg_offsets[reg]; + return *(u32 *)p; +} + +static inline void put_reg_val(struct pt_regs *fp, int reg, u32 val) +{ + u8 *p = ((u8 *)fp) + reg_offsets[reg]; + *(u32 *)p = val; +} + +/* + * (mis)alignment handler + */ +asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause) +{ + u32 isn, addr, val; + int in_kernel; + u8 a, b, d0, d1, d2, d3; + s16 imm16; + unsigned int fault; + + /* back up one instruction */ + fp->ea -= 4; + + if (fixup_exception(fp)) { + return; + } + + in_kernel = !user_mode(fp); + + isn = *(unsigned long *)(fp->ea); + + fault = 0; + + /* do fixup if in kernel or mode turned on */ + if (in_kernel || (ma_usermode & UM_FIXUP)) { + /* decompose instruction */ + a = (isn >> 27) & 0x1f; + b = (isn >> 22) & 0x1f; + imm16 = (isn >> 6) & 0xffff; + addr = get_reg_val(fp, a) + imm16; + + /* do fixup to saved registers */ + switch (isn & 0x3f) { + case INST_LDHU: + fault |= __get_user(d0, (u8 *)(addr+0)); + fault |= __get_user(d1, (u8 *)(addr+1)); + val = (d1 << 8) | d0; + put_reg_val(fp, b, val); + break; + case INST_STH: + val = get_reg_val(fp, b); + d1 = val >> 8; + d0 = val >> 0; + if (in_kernel) { + *(u8 *)(addr+0) = d0; + *(u8 *)(addr+1) = d1; + } else { + fault |= __put_user(d0, (u8 *)(addr+0)); + fault |= __put_user(d1, (u8 *)(addr+1)); + } + break; + case INST_LDH: + fault |= __get_user(d0, (u8 *)(addr+0)); + fault |= __get_user(d1, (u8 *)(addr+1)); + val = (short)((d1 << 8) | d0); + put_reg_val(fp, b, val); + break; + case INST_STW: + val = get_reg_val(fp, b); + d3 = val >> 24; + d2 = val >> 16; + d1 = val >> 8; + d0 = val >> 0; + if (in_kernel) { + *(u8 *)(addr+0) = d0; + *(u8 *)(addr+1) = d1; + *(u8 *)(addr+2) = d2; + *(u8 *)(addr+3) = d3; + } else { + fault |= __put_user(d0, (u8 *)(addr+0)); + fault |= __put_user(d1, (u8 *)(addr+1)); + fault |= __put_user(d2, (u8 *)(addr+2)); + fault |= __put_user(d3, (u8 *)(addr+3)); + } + break; + case INST_LDW: + fault |= __get_user(d0, (u8 *)(addr+0)); + fault |= __get_user(d1, (u8 *)(addr+1)); + fault |= __get_user(d2, (u8 *)(addr+2)); + fault |= __get_user(d3, (u8 *)(addr+3)); + val = (d3 << 24) | (d2 << 16) | (d1 << 8) | d0; + put_reg_val(fp, b, val); + break; + } + } + + addr = RDCTL(CTL_BADADDR); + cause >>= 2; + + if (fault) { + if (in_kernel) { + pr_err("fault during kernel misaligned fixup @ %#lx; addr 0x%08x; isn=0x%08x\n", + fp->ea, (unsigned int)addr, + (unsigned int)isn); + } else { + pr_err("fault during user misaligned fixup @ %#lx; isn=%08x addr=0x%08x sp=0x%08lx pid=%d\n", + fp->ea, + (unsigned int)isn, addr, fp->sp, + current->pid); + + _exception(SIGSEGV, fp, SEGV_MAPERR, fp->ea); + return; + } + } + + /* + * kernel mode - + * note exception and skip bad instruction (return) + */ + if (in_kernel) { + fp->ea += 4; + + if (ma_usermode & KM_WARN) { + pr_err("kernel unaligned access @ %#lx; BADADDR 0x%08x; cause=%d, isn=0x%08x\n", + fp->ea, + (unsigned int)addr, cause, + (unsigned int)isn); + /* show_regs(fp); */ + } + + return; + } + + /* + * user mode - + * possibly warn, + * possibly send SIGBUS signal to process + */ + if (ma_usermode & UM_WARN) { + pr_err("user unaligned access @ %#lx; isn=0x%08lx ea=0x%08lx ra=0x%08lx sp=0x%08lx\n", + (unsigned long)addr, (unsigned long)isn, + fp->ea, fp->ra, fp->sp); + } + + if (ma_usermode & UM_SIGNAL) + _exception(SIGBUS, fp, BUS_ADRALN, fp->ea); + else + fp->ea += 4; /* else advance */ +} + +static void __init misaligned_calc_reg_offsets(void) +{ + int i, r, offset; + + /* pre-calc offsets of registers on sys call stack frame */ + offset = 0; + + /* struct pt_regs */ + for (i = 0; i < 16; i++) { + r = sys_stack_frame_reg_offset[i]; + reg_offsets[r] = offset; + offset += 4; + } + + /* struct switch_stack */ + offset = -sizeof(struct switch_stack); + for (i = 16; i < 32; i++) { + r = sys_stack_frame_reg_offset[i]; + reg_offsets[r] = offset; + offset += 4; + } +} + + +static int __init misaligned_init(void) +{ + /* default mode - silent fix */ + ma_usermode = UM_FIXUP | KM_WARN; + + misaligned_calc_reg_offsets(); + + return 0; +} + +fs_initcall(misaligned_init); diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c new file mode 100644 index 000000000..76e0a42d6 --- /dev/null +++ b/arch/nios2/kernel/module.c @@ -0,0 +1,137 @@ +/* + * Kernel module support for Nios II. + * + * Copyright (C) 2004 Microtronix Datacom Ltd. + * Written by Wentao Xu <xuwentao@microtronix.com> + * Copyright (C) 2001, 2003 Rusty Russell + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + +#include <linux/moduleloader.h> +#include <linux/elf.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/kernel.h> + +#include <asm/cacheflush.h> + +/* + * Modules should NOT be allocated with kmalloc for (obvious) reasons. + * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach + * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns + * addresses in 0xc0000000) + */ +void *module_alloc(unsigned long size) +{ + if (size == 0) + return NULL; + return kmalloc(size, GFP_KERNEL); +} + +/* Free memory returned from module_alloc */ +void module_memfree(void *module_region) +{ + kfree(module_region); +} + +int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *mod) +{ + unsigned int i; + Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr; + + pr_debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) { + /* This is where to make the change */ + uint32_t word; + uint32_t *loc + = ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rela[i].r_offset); + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + Elf32_Sym *sym + = ((Elf32_Sym *)sechdrs[symindex].sh_addr + + ELF32_R_SYM(rela[i].r_info)); + uint32_t v = sym->st_value + rela[i].r_addend; + + pr_debug("reltype %d 0x%x name:<%s>\n", + ELF32_R_TYPE(rela[i].r_info), + rela[i].r_offset, strtab + sym->st_name); + + switch (ELF32_R_TYPE(rela[i].r_info)) { + case R_NIOS2_NONE: + break; + case R_NIOS2_BFD_RELOC_32: + *loc += v; + break; + case R_NIOS2_PCREL16: + v -= (uint32_t)loc + 4; + if ((int32_t)v > 0x7fff || + (int32_t)v < -(int32_t)0x8000) { + pr_err("module %s: relocation overflow\n", + mod->name); + return -ENOEXEC; + } + word = *loc; + *loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) | + (word & 0x3f); + break; + case R_NIOS2_CALL26: + if (v & 3) { + pr_err("module %s: dangerous relocation\n", + mod->name); + return -ENOEXEC; + } + if ((v >> 28) != ((uint32_t)loc >> 28)) { + pr_err("module %s: relocation overflow\n", + mod->name); + return -ENOEXEC; + } + *loc = (*loc & 0x3f) | ((v >> 2) << 6); + break; + case R_NIOS2_HI16: + word = *loc; + *loc = ((((word >> 22) << 16) | + ((v >> 16) & 0xffff)) << 6) | (word & 0x3f); + break; + case R_NIOS2_LO16: + word = *loc; + *loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) | + (word & 0x3f); + break; + case R_NIOS2_HIADJ16: + { + Elf32_Addr word2; + + word = *loc; + word2 = ((v >> 16) + ((v >> 15) & 1)) & 0xffff; + *loc = ((((word >> 22) << 16) | word2) << 6) | + (word & 0x3f); + } + break; + + default: + pr_err("module %s: Unknown reloc: %u\n", + mod->name, ELF32_R_TYPE(rela[i].r_info)); + return -ENOEXEC; + } + } + + return 0; +} + +int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *me) +{ + flush_cache_all(); + return 0; +} diff --git a/arch/nios2/kernel/nios2_ksyms.c b/arch/nios2/kernel/nios2_ksyms.c new file mode 100644 index 000000000..54f7b23df --- /dev/null +++ b/arch/nios2/kernel/nios2_ksyms.c @@ -0,0 +1,45 @@ +/* + * Copyright (C) 2004 Microtronix Datacom Ltd + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + +#include <linux/export.h> +#include <linux/string.h> +#include <linux/pgtable.h> + +#include <asm/cacheflush.h> + +/* string functions */ + +EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(memset); +EXPORT_SYMBOL(memmove); + +/* memory management */ + +EXPORT_SYMBOL(empty_zero_page); +EXPORT_SYMBOL(flush_icache_range); + +/* + * libgcc functions - functions that are used internally by the + * compiler... (prototypes are not correct though, but that + * doesn't really matter since they're not versioned). + */ +#define DECLARE_EXPORT(name) extern void name(void); EXPORT_SYMBOL(name) + +DECLARE_EXPORT(__gcc_bcmp); +DECLARE_EXPORT(__divsi3); +DECLARE_EXPORT(__moddi3); +DECLARE_EXPORT(__modsi3); +DECLARE_EXPORT(__udivmoddi4); +DECLARE_EXPORT(__udivsi3); +DECLARE_EXPORT(__umoddi3); +DECLARE_EXPORT(__umodsi3); +DECLARE_EXPORT(__muldi3); +DECLARE_EXPORT(__ucmpdi2); +DECLARE_EXPORT(__lshrdi3); +DECLARE_EXPORT(__ashldi3); +DECLARE_EXPORT(__ashrdi3); diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c new file mode 100644 index 000000000..29593b985 --- /dev/null +++ b/arch/nios2/kernel/process.c @@ -0,0 +1,269 @@ +/* + * Architecture-dependent parts of process handling. + * + * Copyright (C) 2013 Altera Corporation + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2009 Wind River Systems Inc + * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com + * Copyright (C) 2004 Microtronix Datacom Ltd + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/export.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> +#include <linux/mm_types.h> +#include <linux/tick.h> +#include <linux/uaccess.h> + +#include <asm/unistd.h> +#include <asm/traps.h> +#include <asm/cpuinfo.h> + +asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); + +void (*pm_power_off)(void) = NULL; +EXPORT_SYMBOL(pm_power_off); + +void arch_cpu_idle(void) +{ + raw_local_irq_enable(); +} + +/* + * The development boards have no way to pull a board reset. Just jump to the + * cpu reset address and let the boot loader or the code in head.S take care of + * resetting peripherals. + */ +void machine_restart(char *__unused) +{ + pr_notice("Machine restart (%08x)...\n", cpuinfo.reset_addr); + local_irq_disable(); + __asm__ __volatile__ ( + "jmp %0\n\t" + : + : "r" (cpuinfo.reset_addr) + : "r4"); +} + +void machine_halt(void) +{ + pr_notice("Machine halt...\n"); + local_irq_disable(); + for (;;) + ; +} + +/* + * There is no way to power off the development boards. So just spin for now. If + * we ever have a way of resetting a board using a GPIO we should add that here. + */ +void machine_power_off(void) +{ + pr_notice("Machine power off...\n"); + local_irq_disable(); + for (;;) + ; +} + +void show_regs(struct pt_regs *regs) +{ + pr_notice("\n"); + show_regs_print_info(KERN_DEFAULT); + + pr_notice("r1: %08lx r2: %08lx r3: %08lx r4: %08lx\n", + regs->r1, regs->r2, regs->r3, regs->r4); + + pr_notice("r5: %08lx r6: %08lx r7: %08lx r8: %08lx\n", + regs->r5, regs->r6, regs->r7, regs->r8); + + pr_notice("r9: %08lx r10: %08lx r11: %08lx r12: %08lx\n", + regs->r9, regs->r10, regs->r11, regs->r12); + + pr_notice("r13: %08lx r14: %08lx r15: %08lx\n", + regs->r13, regs->r14, regs->r15); + + pr_notice("ra: %08lx fp: %08lx sp: %08lx gp: %08lx\n", + regs->ra, regs->fp, regs->sp, regs->gp); + + pr_notice("ea: %08lx estatus: %08lx\n", + regs->ea, regs->estatus); +} + +void flush_thread(void) +{ +} + +int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) +{ + unsigned long clone_flags = args->flags; + unsigned long usp = args->stack; + unsigned long tls = args->tls; + struct pt_regs *childregs = task_pt_regs(p); + struct pt_regs *regs; + struct switch_stack *stack; + struct switch_stack *childstack = + ((struct switch_stack *)childregs) - 1; + + if (unlikely(args->fn)) { + memset(childstack, 0, + sizeof(struct switch_stack) + sizeof(struct pt_regs)); + + childstack->r16 = (unsigned long) args->fn; + childstack->r17 = (unsigned long) args->fn_arg; + childstack->ra = (unsigned long) ret_from_kernel_thread; + childregs->estatus = STATUS_PIE; + childregs->sp = (unsigned long) childstack; + + p->thread.ksp = (unsigned long) childstack; + p->thread.kregs = childregs; + return 0; + } + + regs = current_pt_regs(); + *childregs = *regs; + childregs->r2 = 0; /* Set the return value for the child. */ + childregs->r7 = 0; + + stack = ((struct switch_stack *) regs) - 1; + *childstack = *stack; + childstack->ra = (unsigned long)ret_from_fork; + p->thread.kregs = childregs; + p->thread.ksp = (unsigned long) childstack; + + if (usp) + childregs->sp = usp; + + /* Initialize tls register. */ + if (clone_flags & CLONE_SETTLS) + childstack->r23 = tls; + + return 0; +} + +/* + * Generic dumping code. Used for panic and debug. + */ +void dump(struct pt_regs *fp) +{ + unsigned long *sp; + unsigned char *tp; + int i; + + pr_emerg("\nCURRENT PROCESS:\n\n"); + pr_emerg("COMM=%s PID=%d\n", current->comm, current->pid); + + if (current->mm) { + pr_emerg("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n", + (int) current->mm->start_code, + (int) current->mm->end_code, + (int) current->mm->start_data, + (int) current->mm->end_data, + (int) current->mm->end_data, + (int) current->mm->brk); + pr_emerg("USER-STACK=%08x KERNEL-STACK=%08x\n\n", + (int) current->mm->start_stack, + (int)(((unsigned long) current) + THREAD_SIZE)); + } + + pr_emerg("PC: %08lx\n", fp->ea); + pr_emerg("SR: %08lx SP: %08lx\n", + (long) fp->estatus, (long) fp); + + pr_emerg("r1: %08lx r2: %08lx r3: %08lx\n", + fp->r1, fp->r2, fp->r3); + + pr_emerg("r4: %08lx r5: %08lx r6: %08lx r7: %08lx\n", + fp->r4, fp->r5, fp->r6, fp->r7); + pr_emerg("r8: %08lx r9: %08lx r10: %08lx r11: %08lx\n", + fp->r8, fp->r9, fp->r10, fp->r11); + pr_emerg("r12: %08lx r13: %08lx r14: %08lx r15: %08lx\n", + fp->r12, fp->r13, fp->r14, fp->r15); + pr_emerg("or2: %08lx ra: %08lx fp: %08lx sp: %08lx\n", + fp->orig_r2, fp->ra, fp->fp, fp->sp); + pr_emerg("\nUSP: %08x TRAPFRAME: %08x\n", + (unsigned int) fp->sp, (unsigned int) fp); + + pr_emerg("\nCODE:"); + tp = ((unsigned char *) fp->ea) - 0x20; + for (sp = (unsigned long *) tp, i = 0; (i < 0x40); i += 4) { + if ((i % 0x10) == 0) + pr_emerg("\n%08x: ", (int) (tp + i)); + pr_emerg("%08x ", (int) *sp++); + } + pr_emerg("\n"); + + pr_emerg("\nKERNEL STACK:"); + tp = ((unsigned char *) fp) - 0x40; + for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) { + if ((i % 0x10) == 0) + pr_emerg("\n%08x: ", (int) (tp + i)); + pr_emerg("%08x ", (int) *sp++); + } + pr_emerg("\n"); + pr_emerg("\n"); + + pr_emerg("\nUSER STACK:"); + tp = (unsigned char *) (fp->sp - 0x10); + for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) { + if ((i % 0x10) == 0) + pr_emerg("\n%08x: ", (int) (tp + i)); + pr_emerg("%08x ", (int) *sp++); + } + pr_emerg("\n\n"); +} + +unsigned long __get_wchan(struct task_struct *p) +{ + unsigned long fp, pc; + unsigned long stack_page; + int count = 0; + + stack_page = (unsigned long)p; + fp = ((struct switch_stack *)p->thread.ksp)->fp; /* ;dgt2 */ + do { + if (fp < stack_page+sizeof(struct task_struct) || + fp >= 8184+stack_page) /* ;dgt2;tmp */ + return 0; + pc = ((unsigned long *)fp)[1]; + if (!in_sched_functions(pc)) + return pc; + fp = *(unsigned long *) fp; + } while (count++ < 16); /* ;dgt2;tmp */ + return 0; +} + +/* + * Do necessary setup to start up a newly executed thread. + * Will startup in user mode (status_extension = 0). + */ +void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) +{ + memset((void *) regs, 0, sizeof(struct pt_regs)); + regs->estatus = ESTATUS_EPIE | ESTATUS_EU; + regs->ea = pc; + regs->sp = sp; +} + +asmlinkage int nios2_clone(unsigned long clone_flags, unsigned long newsp, + int __user *parent_tidptr, int __user *child_tidptr, + unsigned long tls) +{ + struct kernel_clone_args args = { + .flags = (lower_32_bits(clone_flags) & ~CSIGNAL), + .pidfd = parent_tidptr, + .child_tid = child_tidptr, + .parent_tid = parent_tidptr, + .exit_signal = (lower_32_bits(clone_flags) & CSIGNAL), + .stack = newsp, + .tls = tls, + }; + + return kernel_clone(&args); +} diff --git a/arch/nios2/kernel/prom.c b/arch/nios2/kernel/prom.c new file mode 100644 index 000000000..8d98af5c7 --- /dev/null +++ b/arch/nios2/kernel/prom.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Device tree support + * + * Copyright (C) 2013, 2015 Altera Corporation + * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw> + * + * Based on MIPS support for CONFIG_OF device tree support + * + * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com> + */ + +#include <linux/init.h> +#include <linux/types.h> +#include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/io.h> + +#include <asm/sections.h> + +void __init early_init_devtree(void *params) +{ + __be32 *dtb = (u32 *)__dtb_start; +#if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR) + if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) == + OF_DT_HEADER) { + params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR; + early_init_dt_scan(params); + return; + } +#endif + if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER) + params = (void *)__dtb_start; + + early_init_dt_scan(params); +} diff --git a/arch/nios2/kernel/ptrace.c b/arch/nios2/kernel/ptrace.c new file mode 100644 index 000000000..cd62f3107 --- /dev/null +++ b/arch/nios2/kernel/ptrace.c @@ -0,0 +1,145 @@ +/* + * Copyright (C) 2014 Altera Corporation + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + +#include <linux/elf.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/ptrace.h> +#include <linux/regset.h> +#include <linux/sched.h> +#include <linux/sched/task_stack.h> +#include <linux/uaccess.h> +#include <linux/user.h> + +static int genregs_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + const struct pt_regs *regs = task_pt_regs(target); + const struct switch_stack *sw = (struct switch_stack *)regs - 1; + + membuf_zero(&to, 4); // R0 + membuf_write(&to, ®s->r1, 7 * 4); // R1..R7 + membuf_write(&to, ®s->r8, 8 * 4); // R8..R15 + membuf_write(&to, sw, 8 * 4); // R16..R23 + membuf_zero(&to, 2 * 4); /* et and bt */ + membuf_store(&to, regs->gp); + membuf_store(&to, regs->sp); + membuf_store(&to, regs->fp); + membuf_store(&to, regs->ea); + membuf_zero(&to, 4); // PTR_BA + membuf_store(&to, regs->ra); + membuf_store(&to, regs->ea); /* use ea for PC */ + return membuf_zero(&to, (NUM_PTRACE_REG - PTR_PC) * 4); +} + +/* + * Set the thread state from a regset passed in via ptrace + */ +static int genregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + struct pt_regs *regs = task_pt_regs(target); + const struct switch_stack *sw = (struct switch_stack *)regs - 1; + int ret = 0; + +#define REG_IGNORE_RANGE(START, END) \ + if (!ret) \ + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \ + START * 4, (END * 4) + 4); + +#define REG_IN_ONE(PTR, LOC) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), LOC * 4, (LOC * 4) + 4); + +#define REG_IN_RANGE(PTR, START, END) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), START * 4, (END * 4) + 4); + + REG_IGNORE_RANGE(PTR_R0, PTR_R0); + REG_IN_RANGE(®s->r1, PTR_R1, PTR_R7); + REG_IN_RANGE(®s->r8, PTR_R8, PTR_R15); + REG_IN_RANGE(sw, PTR_R16, PTR_R23); + REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */ + REG_IN_ONE(®s->gp, PTR_GP); + REG_IN_ONE(®s->sp, PTR_SP); + REG_IN_ONE(®s->fp, PTR_FP); + REG_IN_ONE(®s->ea, PTR_EA); + REG_IGNORE_RANGE(PTR_BA, PTR_BA); + REG_IN_ONE(®s->ra, PTR_RA); + REG_IN_ONE(®s->ea, PTR_PC); /* use ea for PC */ + if (!ret) + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, + PTR_STATUS * 4, -1); + + return ret; +} + +/* + * Define the register sets available on Nios2 under Linux + */ +enum nios2_regset { + REGSET_GENERAL, +}; + +static const struct user_regset nios2_regsets[] = { + [REGSET_GENERAL] = { + .core_note_type = NT_PRSTATUS, + .n = NUM_PTRACE_REG, + .size = sizeof(unsigned long), + .align = sizeof(unsigned long), + .regset_get = genregs_get, + .set = genregs_set, + } +}; + +static const struct user_regset_view nios2_user_view = { + .name = "nios2", + .e_machine = ELF_ARCH, + .ei_osabi = ELF_OSABI, + .regsets = nios2_regsets, + .n = ARRAY_SIZE(nios2_regsets) +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &nios2_user_view; +} + +void ptrace_disable(struct task_struct *child) +{ + +} + +long arch_ptrace(struct task_struct *child, long request, unsigned long addr, + unsigned long data) +{ + return ptrace_request(child, request, addr, data); +} + +asmlinkage int do_syscall_trace_enter(void) +{ + int ret = 0; + + if (test_thread_flag(TIF_SYSCALL_TRACE)) + ret = ptrace_report_syscall_entry(task_pt_regs(current)); + + return ret; +} + +asmlinkage void do_syscall_trace_exit(void) +{ + if (test_thread_flag(TIF_SYSCALL_TRACE)) + ptrace_report_syscall_exit(task_pt_regs(current), 0); +} diff --git a/arch/nios2/kernel/setup.c b/arch/nios2/kernel/setup.c new file mode 100644 index 000000000..40bc8fb75 --- /dev/null +++ b/arch/nios2/kernel/setup.c @@ -0,0 +1,197 @@ +/* + * Nios2-specific parts of system setup + * + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd. + * Copyright (C) 2001 Vic Phillips <vic@microtronix.com> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/sched/task.h> +#include <linux/console.h> +#include <linux/memblock.h> +#include <linux/initrd.h> +#include <linux/of_fdt.h> +#include <linux/screen_info.h> + +#include <asm/mmu_context.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/cpuinfo.h> + +unsigned long memory_start; +EXPORT_SYMBOL(memory_start); + +unsigned long memory_end; +EXPORT_SYMBOL(memory_end); + +static struct pt_regs fake_regs = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, + 0}; + +#ifdef CONFIG_VT +struct screen_info screen_info; +#endif + +/* Copy a short hook instruction sequence to the exception address */ +static inline void copy_exception_handler(unsigned int addr) +{ + unsigned int start = (unsigned int) exception_handler_hook; + volatile unsigned int tmp = 0; + + if (start == addr) { + /* The CPU exception address already points to the handler. */ + return; + } + + __asm__ __volatile__ ( + "ldw %2,0(%0)\n" + "stw %2,0(%1)\n" + "ldw %2,4(%0)\n" + "stw %2,4(%1)\n" + "ldw %2,8(%0)\n" + "stw %2,8(%1)\n" + "flushd 0(%1)\n" + "flushd 4(%1)\n" + "flushd 8(%1)\n" + "flushi %1\n" + "addi %1,%1,4\n" + "flushi %1\n" + "addi %1,%1,4\n" + "flushi %1\n" + "flushp\n" + : /* no output registers */ + : "r" (start), "r" (addr), "r" (tmp) + : "memory" + ); +} + +/* Copy the fast TLB miss handler */ +static inline void copy_fast_tlb_miss_handler(unsigned int addr) +{ + unsigned int start = (unsigned int) fast_handler; + unsigned int end = (unsigned int) fast_handler_end; + volatile unsigned int tmp = 0; + + __asm__ __volatile__ ( + "1:\n" + " ldw %3,0(%0)\n" + " stw %3,0(%1)\n" + " flushd 0(%1)\n" + " flushi %1\n" + " flushp\n" + " addi %0,%0,4\n" + " addi %1,%1,4\n" + " bne %0,%2,1b\n" + : /* no output registers */ + : "r" (start), "r" (addr), "r" (end), "r" (tmp) + : "memory" + ); +} + +/* + * save args passed from u-boot, called from head.S + * + * @r4: NIOS magic + * @r5: initrd start + * @r6: initrd end or fdt + * @r7: kernel command line + */ +asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6, + unsigned r7) +{ + unsigned dtb_passed = 0; + char cmdline_passed[COMMAND_LINE_SIZE] __maybe_unused = { 0, }; + +#if defined(CONFIG_NIOS2_PASS_CMDLINE) + if (r4 == 0x534f494e) { /* r4 is magic NIOS */ +#if defined(CONFIG_BLK_DEV_INITRD) + if (r5) { /* initramfs */ + initrd_start = r5; + initrd_end = r6; + } +#endif /* CONFIG_BLK_DEV_INITRD */ + dtb_passed = r6; + + if (r7) + strlcpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE); + } +#endif + + early_init_devtree((void *)dtb_passed); + +#ifndef CONFIG_CMDLINE_FORCE + if (cmdline_passed[0]) + strlcpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE); +#ifdef CONFIG_NIOS2_CMDLINE_IGNORE_DTB + else + strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE); +#endif +#endif + + parse_early_param(); +} + +static void __init find_limits(unsigned long *min, unsigned long *max_low, + unsigned long *max_high) +{ + *max_low = PFN_DOWN(memblock_get_current_limit()); + *min = PFN_UP(memblock_start_of_DRAM()); + *max_high = PFN_DOWN(memblock_end_of_DRAM()); +} + +void __init setup_arch(char **cmdline_p) +{ + console_verbose(); + + memory_start = memblock_start_of_DRAM(); + memory_end = memblock_end_of_DRAM(); + + setup_initial_init_mm(_stext, _etext, _edata, _end); + init_task.thread.kregs = &fake_regs; + + /* Keep a copy of command line */ + *cmdline_p = boot_command_line; + + find_limits(&min_low_pfn, &max_low_pfn, &max_pfn); + max_mapnr = max_low_pfn; + + memblock_reserve(__pa_symbol(_stext), _end - _stext); +#ifdef CONFIG_BLK_DEV_INITRD + if (initrd_start) { + memblock_reserve(virt_to_phys((void *)initrd_start), + initrd_end - initrd_start); + } +#endif /* CONFIG_BLK_DEV_INITRD */ + + early_init_fdt_reserve_self(); + early_init_fdt_scan_reserved_mem(); + + unflatten_and_copy_device_tree(); + + setup_cpuinfo(); + + copy_exception_handler(cpuinfo.exception_addr); + + mmu_init(); + + copy_fast_tlb_miss_handler(cpuinfo.fast_tlb_miss_exc_addr); + + /* + * Initialize MMU context handling here because data from cpuinfo is + * needed for this. + */ + mmu_context_init(); + + /* + * get kmalloc into gear + */ + paging_init(); +} diff --git a/arch/nios2/kernel/signal.c b/arch/nios2/kernel/signal.c new file mode 100644 index 000000000..a5b93a30c --- /dev/null +++ b/arch/nios2/kernel/signal.c @@ -0,0 +1,328 @@ +/* + * Copyright (C) 2013-2014 Altera Corporation + * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd + * Copyright (C) 1991, 1992 Linus Torvalds + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/uaccess.h> +#include <linux/unistd.h> +#include <linux/personality.h> +#include <linux/resume_user_mode.h> + +#include <asm/ucontext.h> +#include <asm/cacheflush.h> + +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) + +/* + * Do a signal return; undo the signal stack. + * + * Keep the return code on the stack quadword aligned! + * That makes the cache flush below easier. + */ + +struct rt_sigframe { + struct siginfo info; + struct ucontext uc; +}; + +static inline int rt_restore_ucontext(struct pt_regs *regs, + struct switch_stack *sw, + struct ucontext __user *uc, int *pr2) +{ + int temp; + unsigned long __user *gregs = uc->uc_mcontext.gregs; + int err; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + err = __get_user(temp, &uc->uc_mcontext.version); + if (temp != MCONTEXT_VERSION) + goto badframe; + /* restore passed registers */ + err |= __get_user(regs->r1, &gregs[0]); + err |= __get_user(regs->r2, &gregs[1]); + err |= __get_user(regs->r3, &gregs[2]); + err |= __get_user(regs->r4, &gregs[3]); + err |= __get_user(regs->r5, &gregs[4]); + err |= __get_user(regs->r6, &gregs[5]); + err |= __get_user(regs->r7, &gregs[6]); + err |= __get_user(regs->r8, &gregs[7]); + err |= __get_user(regs->r9, &gregs[8]); + err |= __get_user(regs->r10, &gregs[9]); + err |= __get_user(regs->r11, &gregs[10]); + err |= __get_user(regs->r12, &gregs[11]); + err |= __get_user(regs->r13, &gregs[12]); + err |= __get_user(regs->r14, &gregs[13]); + err |= __get_user(regs->r15, &gregs[14]); + err |= __get_user(sw->r16, &gregs[15]); + err |= __get_user(sw->r17, &gregs[16]); + err |= __get_user(sw->r18, &gregs[17]); + err |= __get_user(sw->r19, &gregs[18]); + err |= __get_user(sw->r20, &gregs[19]); + err |= __get_user(sw->r21, &gregs[20]); + err |= __get_user(sw->r22, &gregs[21]); + err |= __get_user(sw->r23, &gregs[22]); + /* gregs[23] is handled below */ + err |= __get_user(sw->fp, &gregs[24]); /* Verify, should this be + settable */ + err |= __get_user(sw->gp, &gregs[25]); /* Verify, should this be + settable */ + + err |= __get_user(temp, &gregs[26]); /* Not really necessary no user + settable bits */ + err |= __get_user(regs->ea, &gregs[27]); + + err |= __get_user(regs->ra, &gregs[23]); + err |= __get_user(regs->sp, &gregs[28]); + + regs->orig_r2 = -1; /* disable syscall checks */ + + err |= restore_altstack(&uc->uc_stack); + if (err) + goto badframe; + + *pr2 = regs->r2; + return err; + +badframe: + return 1; +} + +asmlinkage int do_rt_sigreturn(struct switch_stack *sw) +{ + struct pt_regs *regs = (struct pt_regs *)(sw + 1); + /* Verify, can we follow the stack back */ + struct rt_sigframe __user *frame; + sigset_t set; + int rval; + + frame = (struct rt_sigframe __user *) regs->sp; + if (!access_ok(frame, sizeof(*frame))) + goto badframe; + + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + set_current_blocked(&set); + + if (rt_restore_ucontext(regs, sw, &frame->uc, &rval)) + goto badframe; + + return rval; + +badframe: + force_sig(SIGSEGV); + return 0; +} + +static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) +{ + struct switch_stack *sw = (struct switch_stack *)regs - 1; + unsigned long __user *gregs = uc->uc_mcontext.gregs; + int err = 0; + + err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); + err |= __put_user(regs->r1, &gregs[0]); + err |= __put_user(regs->r2, &gregs[1]); + err |= __put_user(regs->r3, &gregs[2]); + err |= __put_user(regs->r4, &gregs[3]); + err |= __put_user(regs->r5, &gregs[4]); + err |= __put_user(regs->r6, &gregs[5]); + err |= __put_user(regs->r7, &gregs[6]); + err |= __put_user(regs->r8, &gregs[7]); + err |= __put_user(regs->r9, &gregs[8]); + err |= __put_user(regs->r10, &gregs[9]); + err |= __put_user(regs->r11, &gregs[10]); + err |= __put_user(regs->r12, &gregs[11]); + err |= __put_user(regs->r13, &gregs[12]); + err |= __put_user(regs->r14, &gregs[13]); + err |= __put_user(regs->r15, &gregs[14]); + err |= __put_user(sw->r16, &gregs[15]); + err |= __put_user(sw->r17, &gregs[16]); + err |= __put_user(sw->r18, &gregs[17]); + err |= __put_user(sw->r19, &gregs[18]); + err |= __put_user(sw->r20, &gregs[19]); + err |= __put_user(sw->r21, &gregs[20]); + err |= __put_user(sw->r22, &gregs[21]); + err |= __put_user(sw->r23, &gregs[22]); + err |= __put_user(regs->ra, &gregs[23]); + err |= __put_user(sw->fp, &gregs[24]); + err |= __put_user(sw->gp, &gregs[25]); + err |= __put_user(regs->ea, &gregs[27]); + err |= __put_user(regs->sp, &gregs[28]); + return err; +} + +static inline void __user *get_sigframe(struct ksignal *ksig, + struct pt_regs *regs, + size_t frame_size) +{ + unsigned long usp; + + /* Default to using normal stack. */ + usp = regs->sp; + + /* This is the X/Open sanctioned signal stack switching. */ + usp = sigsp(usp, ksig); + + /* Verify, is it 32 or 64 bit aligned */ + return (void __user *)((usp - frame_size) & -8UL); +} + +static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, + struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + int err = 0; + + frame = get_sigframe(ksig, regs, sizeof(*frame)); + + if (ksig->ka.sa.sa_flags & SA_SIGINFO) + err |= copy_siginfo_to_user(&frame->info, &ksig->info); + + /* Create the ucontext. */ + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(0, &frame->uc.uc_link); + err |= __save_altstack(&frame->uc.uc_stack, regs->sp); + err |= rt_setup_ucontext(&frame->uc, regs); + err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + + if (err) + goto give_sigsegv; + + /* Set up to return from userspace; jump to fixed address sigreturn + trampoline on kuser page. */ + regs->ra = (unsigned long) (0x1044); + + /* Set up registers for signal handler */ + regs->sp = (unsigned long) frame; + regs->r4 = (unsigned long) ksig->sig; + regs->r5 = (unsigned long) &frame->info; + regs->r6 = (unsigned long) &frame->uc; + regs->ea = (unsigned long) ksig->ka.sa.sa_handler; + return 0; + +give_sigsegv: + force_sigsegv(ksig->sig); + return -EFAULT; +} + +/* + * OK, we're invoking a handler + */ +static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) +{ + int ret; + sigset_t *oldset = sigmask_to_save(); + + /* set up the stack frame */ + ret = setup_rt_frame(ksig, oldset, regs); + + signal_setup_done(ret, ksig, 0); +} + +static int do_signal(struct pt_regs *regs) +{ + unsigned int retval = 0, continue_addr = 0, restart_addr = 0; + int restart = 0; + struct ksignal ksig; + + current->thread.kregs = regs; + + /* + * If we were from a system call, check for system call restarting... + */ + if (regs->orig_r2 >= 0 && regs->r1) { + continue_addr = regs->ea; + restart_addr = continue_addr - 4; + retval = regs->r2; + + /* + * Prepare for system call restart. We do this here so that a + * debugger will see the already changed PC. + */ + switch (retval) { + case ERESTART_RESTARTBLOCK: + restart = -2; + fallthrough; + case ERESTARTNOHAND: + case ERESTARTSYS: + case ERESTARTNOINTR: + restart++; + regs->r2 = regs->orig_r2; + regs->r7 = regs->orig_r7; + regs->ea = restart_addr; + break; + } + regs->orig_r2 = -1; + } + + if (get_signal(&ksig)) { + /* handler */ + if (unlikely(restart && regs->ea == restart_addr)) { + if (retval == ERESTARTNOHAND || + retval == ERESTART_RESTARTBLOCK || + (retval == ERESTARTSYS + && !(ksig.ka.sa.sa_flags & SA_RESTART))) { + regs->r2 = EINTR; + regs->r7 = 1; + regs->ea = continue_addr; + } + } + handle_signal(&ksig, regs); + return 0; + } + + /* + * No handler present + */ + if (unlikely(restart) && regs->ea == restart_addr) { + regs->ea = continue_addr; + regs->r2 = __NR_restart_syscall; + } + + /* + * If there's no signal to deliver, we just put the saved sigmask back. + */ + restore_saved_sigmask(); + + return restart; +} + +asmlinkage int do_notify_resume(struct pt_regs *regs) +{ + /* + * We want the common case to go fast, which is why we may in certain + * cases get here from kernel mode. Just return without doing anything + * if so. + */ + if (!user_mode(regs)) + return 0; + + if (test_thread_flag(TIF_SIGPENDING) || + test_thread_flag(TIF_NOTIFY_SIGNAL)) { + int restart = do_signal(regs); + + if (unlikely(restart)) { + /* + * Restart without handlers. + * Deal with it without leaving + * the kernel space. + */ + return restart; + } + } else if (test_thread_flag(TIF_NOTIFY_RESUME)) + resume_user_mode_work(regs); + + return 0; +} diff --git a/arch/nios2/kernel/sys_nios2.c b/arch/nios2/kernel/sys_nios2.c new file mode 100644 index 000000000..b1ca85699 --- /dev/null +++ b/arch/nios2/kernel/sys_nios2.c @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2013 Altera Corporation + * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/export.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/slab.h> +#include <linux/syscalls.h> + +#include <asm/cacheflush.h> +#include <asm/traps.h> + +/* sys_cacheflush -- flush the processor cache. */ +asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len, + unsigned int op) +{ + struct vm_area_struct *vma; + struct mm_struct *mm = current->mm; + + if (len == 0) + return 0; + + /* We only support op 0 now, return error if op is non-zero.*/ + if (op) + return -EINVAL; + + /* Check for overflow */ + if (addr + len < addr) + return -EFAULT; + + if (mmap_read_lock_killable(mm)) + return -EINTR; + + /* + * Verify that the specified address region actually belongs + * to this process. + */ + vma = find_vma(mm, addr); + if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) { + mmap_read_unlock(mm); + return -EFAULT; + } + + flush_cache_range(vma, addr, addr + len); + + mmap_read_unlock(mm); + return 0; +} + +asmlinkage int sys_getpagesize(void) +{ + return PAGE_SIZE; +} diff --git a/arch/nios2/kernel/syscall_table.c b/arch/nios2/kernel/syscall_table.c new file mode 100644 index 000000000..c2875a6dd --- /dev/null +++ b/arch/nios2/kernel/syscall_table.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright Altera Corporation (C) 2013. All rights reserved + */ + +#include <linux/syscalls.h> +#include <linux/signal.h> +#include <linux/unistd.h> + +#include <asm/syscalls.h> + +#undef __SYSCALL +#define __SYSCALL(nr, call) [nr] = (call), + +void *sys_call_table[__NR_syscalls] = { + [0 ... __NR_syscalls-1] = sys_ni_syscall, +#include <asm/unistd.h> +}; diff --git a/arch/nios2/kernel/time.c b/arch/nios2/kernel/time.c new file mode 100644 index 000000000..54467d008 --- /dev/null +++ b/arch/nios2/kernel/time.c @@ -0,0 +1,359 @@ +/* + * Copyright (C) 2013-2014 Altera Corporation + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/io.h> +#include <linux/slab.h> + +#define ALTR_TIMER_COMPATIBLE "altr,timer-1.0" + +#define ALTERA_TIMER_STATUS_REG 0 +#define ALTERA_TIMER_CONTROL_REG 4 +#define ALTERA_TIMER_PERIODL_REG 8 +#define ALTERA_TIMER_PERIODH_REG 12 +#define ALTERA_TIMER_SNAPL_REG 16 +#define ALTERA_TIMER_SNAPH_REG 20 + +#define ALTERA_TIMER_CONTROL_ITO_MSK (0x1) +#define ALTERA_TIMER_CONTROL_CONT_MSK (0x2) +#define ALTERA_TIMER_CONTROL_START_MSK (0x4) +#define ALTERA_TIMER_CONTROL_STOP_MSK (0x8) + +struct nios2_timer { + void __iomem *base; + unsigned long freq; +}; + +struct nios2_clockevent_dev { + struct nios2_timer timer; + struct clock_event_device ced; +}; + +struct nios2_clocksource { + struct nios2_timer timer; + struct clocksource cs; +}; + +static inline struct nios2_clockevent_dev * + to_nios2_clkevent(struct clock_event_device *evt) +{ + return container_of(evt, struct nios2_clockevent_dev, ced); +} + +static inline struct nios2_clocksource * + to_nios2_clksource(struct clocksource *cs) +{ + return container_of(cs, struct nios2_clocksource, cs); +} + +static u16 timer_readw(struct nios2_timer *timer, u32 offs) +{ + return readw(timer->base + offs); +} + +static void timer_writew(struct nios2_timer *timer, u16 val, u32 offs) +{ + writew(val, timer->base + offs); +} + +static inline unsigned long read_timersnapshot(struct nios2_timer *timer) +{ + unsigned long count; + + timer_writew(timer, 0, ALTERA_TIMER_SNAPL_REG); + count = timer_readw(timer, ALTERA_TIMER_SNAPH_REG) << 16 | + timer_readw(timer, ALTERA_TIMER_SNAPL_REG); + + return count; +} + +static u64 nios2_timer_read(struct clocksource *cs) +{ + struct nios2_clocksource *nios2_cs = to_nios2_clksource(cs); + unsigned long flags; + u32 count; + + local_irq_save(flags); + count = read_timersnapshot(&nios2_cs->timer); + local_irq_restore(flags); + + /* Counter is counting down */ + return ~count; +} + +static struct nios2_clocksource nios2_cs = { + .cs = { + .name = "nios2-clksrc", + .rating = 250, + .read = nios2_timer_read, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + }, +}; + +cycles_t get_cycles(void) +{ + /* Only read timer if it has been initialized */ + if (nios2_cs.timer.base) + return nios2_timer_read(&nios2_cs.cs); + return 0; +} +EXPORT_SYMBOL(get_cycles); + +static void nios2_timer_start(struct nios2_timer *timer) +{ + u16 ctrl; + + ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG); + ctrl |= ALTERA_TIMER_CONTROL_START_MSK; + timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG); +} + +static void nios2_timer_stop(struct nios2_timer *timer) +{ + u16 ctrl; + + ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG); + ctrl |= ALTERA_TIMER_CONTROL_STOP_MSK; + timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG); +} + +static void nios2_timer_config(struct nios2_timer *timer, unsigned long period, + bool periodic) +{ + u16 ctrl; + + /* The timer's actual period is one cycle greater than the value + * stored in the period register. */ + period--; + + ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG); + /* stop counter */ + timer_writew(timer, ctrl | ALTERA_TIMER_CONTROL_STOP_MSK, + ALTERA_TIMER_CONTROL_REG); + + /* write new count */ + timer_writew(timer, period, ALTERA_TIMER_PERIODL_REG); + timer_writew(timer, period >> 16, ALTERA_TIMER_PERIODH_REG); + + ctrl |= ALTERA_TIMER_CONTROL_START_MSK | ALTERA_TIMER_CONTROL_ITO_MSK; + if (periodic) + ctrl |= ALTERA_TIMER_CONTROL_CONT_MSK; + else + ctrl &= ~ALTERA_TIMER_CONTROL_CONT_MSK; + timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG); +} + +static int nios2_timer_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt); + + nios2_timer_config(&nios2_ced->timer, delta, false); + + return 0; +} + +static int nios2_timer_shutdown(struct clock_event_device *evt) +{ + struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt); + struct nios2_timer *timer = &nios2_ced->timer; + + nios2_timer_stop(timer); + return 0; +} + +static int nios2_timer_set_periodic(struct clock_event_device *evt) +{ + unsigned long period; + struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt); + struct nios2_timer *timer = &nios2_ced->timer; + + period = DIV_ROUND_UP(timer->freq, HZ); + nios2_timer_config(timer, period, true); + return 0; +} + +static int nios2_timer_resume(struct clock_event_device *evt) +{ + struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt); + struct nios2_timer *timer = &nios2_ced->timer; + + nios2_timer_start(timer); + return 0; +} + +irqreturn_t timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = (struct clock_event_device *) dev_id; + struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt); + + /* Clear the interrupt condition */ + timer_writew(&nios2_ced->timer, 0, ALTERA_TIMER_STATUS_REG); + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static int __init nios2_timer_get_base_and_freq(struct device_node *np, + void __iomem **base, u32 *freq) +{ + *base = of_iomap(np, 0); + if (!*base) { + pr_crit("Unable to map reg for %pOFn\n", np); + return -ENXIO; + } + + if (of_property_read_u32(np, "clock-frequency", freq)) { + pr_crit("Unable to get %pOFn clock frequency\n", np); + return -EINVAL; + } + + return 0; +} + +static struct nios2_clockevent_dev nios2_ce = { + .ced = { + .name = "nios2-clkevent", + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .rating = 250, + .shift = 32, + .set_next_event = nios2_timer_set_next_event, + .set_state_shutdown = nios2_timer_shutdown, + .set_state_periodic = nios2_timer_set_periodic, + .set_state_oneshot = nios2_timer_shutdown, + .tick_resume = nios2_timer_resume, + }, +}; + +static __init int nios2_clockevent_init(struct device_node *timer) +{ + void __iomem *iobase; + u32 freq; + int irq, ret; + + ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq); + if (ret) + return ret; + + irq = irq_of_parse_and_map(timer, 0); + if (!irq) { + pr_crit("Unable to parse timer irq\n"); + return -EINVAL; + } + + nios2_ce.timer.base = iobase; + nios2_ce.timer.freq = freq; + + nios2_ce.ced.cpumask = cpumask_of(0); + nios2_ce.ced.irq = irq; + + nios2_timer_stop(&nios2_ce.timer); + /* clear pending interrupt */ + timer_writew(&nios2_ce.timer, 0, ALTERA_TIMER_STATUS_REG); + + ret = request_irq(irq, timer_interrupt, IRQF_TIMER, timer->name, + &nios2_ce.ced); + if (ret) { + pr_crit("Unable to setup timer irq\n"); + return ret; + } + + clockevents_config_and_register(&nios2_ce.ced, freq, 1, ULONG_MAX); + + return 0; +} + +static __init int nios2_clocksource_init(struct device_node *timer) +{ + unsigned int ctrl; + void __iomem *iobase; + u32 freq; + int ret; + + ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq); + if (ret) + return ret; + + nios2_cs.timer.base = iobase; + nios2_cs.timer.freq = freq; + + ret = clocksource_register_hz(&nios2_cs.cs, freq); + if (ret) + return ret; + + timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODL_REG); + timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODH_REG); + + /* interrupt disable + continuous + start */ + ctrl = ALTERA_TIMER_CONTROL_CONT_MSK | ALTERA_TIMER_CONTROL_START_MSK; + timer_writew(&nios2_cs.timer, ctrl, ALTERA_TIMER_CONTROL_REG); + + /* Calibrate the delay loop directly */ + lpj_fine = freq / HZ; + + return 0; +} + +/* + * The first timer instance will use as a clockevent. If there are two or + * more instances, the second one gets used as clocksource and all + * others are unused. +*/ +static int __init nios2_time_init(struct device_node *timer) +{ + static int num_called; + int ret; + + switch (num_called) { + case 0: + ret = nios2_clockevent_init(timer); + break; + case 1: + ret = nios2_clocksource_init(timer); + break; + default: + ret = 0; + break; + } + + num_called++; + + return ret; +} + +void read_persistent_clock64(struct timespec64 *ts) +{ + ts->tv_sec = mktime64(2007, 1, 1, 0, 0, 0); + ts->tv_nsec = 0; +} + +void __init time_init(void) +{ + struct device_node *np; + int count = 0; + + for_each_compatible_node(np, NULL, ALTR_TIMER_COMPATIBLE) + count++; + + if (count < 2) + panic("%d timer is found, it needs 2 timers in system\n", count); + + timer_probe(); +} + +TIMER_OF_DECLARE(nios2_timer, ALTR_TIMER_COMPATIBLE, nios2_time_init); diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c new file mode 100644 index 000000000..85ac49d64 --- /dev/null +++ b/arch/nios2/kernel/traps.c @@ -0,0 +1,196 @@ +/* + * Hardware exception handling + * + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd. + * Copyright (C) 2001 Vic Phillips + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/ptrace.h> + +#include <asm/traps.h> +#include <asm/sections.h> +#include <linux/uaccess.h> + +static DEFINE_SPINLOCK(die_lock); + +static void _send_sig(int signo, int code, unsigned long addr) +{ + force_sig_fault(signo, code, (void __user *) addr); +} + +void die(const char *str, struct pt_regs *regs, long err) +{ + console_verbose(); + spin_lock_irq(&die_lock); + pr_warn("Oops: %s, sig: %ld\n", str, err); + show_regs(regs); + spin_unlock_irq(&die_lock); + /* + * make_task_dead() should take care of panic'ing from an interrupt + * context so we don't handle it here + */ + make_task_dead(err); +} + +void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr) +{ + if (!user_mode(regs)) + die("Exception in kernel mode", regs, signo); + + _send_sig(signo, code, addr); +} + +/* + * The show_stack() is external API which we do not use ourselves. + */ + +int kstack_depth_to_print = 48; + +void show_stack(struct task_struct *task, unsigned long *stack, + const char *loglvl) +{ + unsigned long *endstack, addr; + int i; + + if (!stack) { + if (task) + stack = (unsigned long *)task->thread.ksp; + else + stack = (unsigned long *)&stack; + } + + addr = (unsigned long) stack; + endstack = (unsigned long *) PAGE_ALIGN(addr); + + printk("%sStack from %08lx:", loglvl, (unsigned long)stack); + for (i = 0; i < kstack_depth_to_print; i++) { + if (stack + 1 > endstack) + break; + if (i % 8 == 0) + printk("%s\n ", loglvl); + printk("%s %08lx", loglvl, *stack++); + } + + printk("%s\nCall Trace:", loglvl); + i = 0; + while (stack + 1 <= endstack) { + addr = *stack++; + /* + * If the address is either in the text segment of the + * kernel, or in the region which contains vmalloc'ed + * memory, it *may* be the address of a calling + * routine; if so, print it so that someone tracing + * down the cause of the crash will be able to figure + * out the call path that was taken. + */ + if (((addr >= (unsigned long) _stext) && + (addr <= (unsigned long) _etext))) { + if (i % 4 == 0) + pr_emerg("\n "); + printk("%s [<%08lx>]", loglvl, addr); + i++; + } + } + printk("%s\n", loglvl); +} + +/* Breakpoint handler */ +asmlinkage void breakpoint_c(struct pt_regs *fp) +{ + /* + * The breakpoint entry code has moved the PC on by 4 bytes, so we must + * move it back. This could be done on the host but we do it here + * because monitor.S of JTAG gdbserver does it too. + */ + fp->ea -= 4; + _exception(SIGTRAP, fp, TRAP_BRKPT, fp->ea); +} + +#ifndef CONFIG_NIOS2_ALIGNMENT_TRAP +/* Alignment exception handler */ +asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause >>= 2; + fp->ea -= 4; + + if (fixup_exception(fp)) + return; + + if (!user_mode(fp)) { + pr_alert("Unaligned access from kernel mode, this might be a hardware\n"); + pr_alert("problem, dump registers and restart the instruction\n"); + pr_alert(" BADADDR 0x%08lx\n", addr); + pr_alert(" cause %d\n", cause); + pr_alert(" op-code 0x%08lx\n", *(unsigned long *)(fp->ea)); + show_regs(fp); + return; + } + + _exception(SIGBUS, fp, BUS_ADRALN, addr); +} +#endif /* CONFIG_NIOS2_ALIGNMENT_TRAP */ + +/* Illegal instruction handler */ +asmlinkage void handle_illegal_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_ILLOPC, fp->ea); +} + +/* Supervisor instruction handler */ +asmlinkage void handle_supervisor_instr(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_PRVOPC, fp->ea); +} + +/* Division error handler */ +asmlinkage void handle_diverror_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGFPE, fp, FPE_INTDIV, fp->ea); +} + +/* Unhandled exception handler */ +asmlinkage void unhandled_exception(struct pt_regs *regs, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause /= 4; + + pr_emerg("Unhandled exception #%d in %s mode (badaddr=0x%08lx)\n", + cause, user_mode(regs) ? "user" : "kernel", addr); + + regs->ea -= 4; + show_regs(regs); + + pr_emerg("opcode: 0x%08lx\n", *(unsigned long *)(regs->ea)); +} + +asmlinkage void handle_trap_1_c(struct pt_regs *fp) +{ + _send_sig(SIGUSR1, 0, fp->ea); +} + +asmlinkage void handle_trap_2_c(struct pt_regs *fp) +{ + _send_sig(SIGUSR2, 0, fp->ea); +} + +asmlinkage void handle_trap_3_c(struct pt_regs *fp) +{ + _send_sig(SIGILL, ILL_ILLTRP, fp->ea); +} diff --git a/arch/nios2/kernel/vmlinux.lds.S b/arch/nios2/kernel/vmlinux.lds.S new file mode 100644 index 000000000..126e11474 --- /dev/null +++ b/arch/nios2/kernel/vmlinux.lds.S @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw> + */ +#include <asm/page.h> +#include <asm-generic/vmlinux.lds.h> +#include <asm/cache.h> +#include <asm/thread_info.h> + +OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2") + +OUTPUT_ARCH(nios) +ENTRY(_start) /* Defined in head.S */ + +jiffies = jiffies_64; + +SECTIONS +{ + . = CONFIG_NIOS2_MEM_BASE | CONFIG_NIOS2_KERNEL_REGION_BASE; + + _text = .; + _stext = .; + HEAD_TEXT_SECTION + .text : { + TEXT_TEXT + SCHED_TEXT + CPUIDLE_TEXT + LOCK_TEXT + IRQENTRY_TEXT + SOFTIRQENTRY_TEXT + KPROBES_TEXT + } =0 + _etext = .; + + .got : { + *(.got.plt) + *(.igot.plt) + *(.got) + *(.igot) + } + + EXCEPTION_TABLE(L1_CACHE_BYTES) + + . = ALIGN(PAGE_SIZE); + __init_begin = .; + INIT_TEXT_SECTION(PAGE_SIZE) + INIT_DATA_SECTION(PAGE_SIZE) + PERCPU_SECTION(L1_CACHE_BYTES) + __init_end = .; + + _sdata = .; + RO_DATA(PAGE_SIZE) + RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE) + _edata = .; + + BSS_SECTION(0, 0, 0) + _end = .; + + STABS_DEBUG + DWARF_DEBUG + ELF_DETAILS + + DISCARDS +} |