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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/sh/kernel/cpu/init.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/sh/kernel/cpu/init.c')
-rw-r--r-- | arch/sh/kernel/cpu/init.c | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/init.c b/arch/sh/kernel/cpu/init.c new file mode 100644 index 000000000..c4f01c5c8 --- /dev/null +++ b/arch/sh/kernel/cpu/init.c @@ -0,0 +1,369 @@ +/* + * arch/sh/kernel/cpu/init.c + * + * CPU init code + * + * Copyright (C) 2002 - 2009 Paul Mundt + * Copyright (C) 2003 Richard Curnow + * + * 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/kernel.h> +#include <linux/mm.h> +#include <linux/log2.h> +#include <asm/mmu_context.h> +#include <asm/processor.h> +#include <linux/uaccess.h> +#include <asm/page.h> +#include <asm/cacheflush.h> +#include <asm/cache.h> +#include <asm/elf.h> +#include <asm/io.h> +#include <asm/smp.h> +#include <asm/sh_bios.h> +#include <asm/setup.h> + +#ifdef CONFIG_SH_FPU +#define cpu_has_fpu 1 +#else +#define cpu_has_fpu 0 +#endif + +#ifdef CONFIG_SH_DSP +#define cpu_has_dsp 1 +#else +#define cpu_has_dsp 0 +#endif + +/* + * Generic wrapper for command line arguments to disable on-chip + * peripherals (nofpu, nodsp, and so forth). + */ +#define onchip_setup(x) \ +static int x##_disabled = !cpu_has_##x; \ + \ +static int x##_setup(char *opts) \ +{ \ + x##_disabled = 1; \ + return 1; \ +} \ +__setup("no" __stringify(x), x##_setup); + +onchip_setup(fpu); +onchip_setup(dsp); + +#ifdef CONFIG_SPECULATIVE_EXECUTION +#define CPUOPM 0xff2f0000 +#define CPUOPM_RABD (1 << 5) + +static void speculative_execution_init(void) +{ + /* Clear RABD */ + __raw_writel(__raw_readl(CPUOPM) & ~CPUOPM_RABD, CPUOPM); + + /* Flush the update */ + (void)__raw_readl(CPUOPM); + ctrl_barrier(); +} +#else +#define speculative_execution_init() do { } while (0) +#endif + +#ifdef CONFIG_CPU_SH4A +#define EXPMASK 0xff2f0004 +#define EXPMASK_RTEDS (1 << 0) +#define EXPMASK_BRDSSLP (1 << 1) +#define EXPMASK_MMCAW (1 << 4) + +static void expmask_init(void) +{ + unsigned long expmask = __raw_readl(EXPMASK); + + /* + * Future proofing. + * + * Disable support for slottable sleep instruction, non-nop + * instructions in the rte delay slot, and associative writes to + * the memory-mapped cache array. + */ + expmask &= ~(EXPMASK_RTEDS | EXPMASK_BRDSSLP | EXPMASK_MMCAW); + + __raw_writel(expmask, EXPMASK); + ctrl_barrier(); +} +#else +#define expmask_init() do { } while (0) +#endif + +/* 2nd-level cache init */ +void __attribute__ ((weak)) l2_cache_init(void) +{ +} + +/* + * Generic first-level cache init + */ +#if defined(CONFIG_SUPERH32) && !defined(CONFIG_CPU_J2) +static void cache_init(void) +{ + unsigned long ccr, flags; + + jump_to_uncached(); + ccr = __raw_readl(SH_CCR); + + /* + * At this point we don't know whether the cache is enabled or not - a + * bootloader may have enabled it. There are at least 2 things that + * could be dirty in the cache at this point: + * 1. kernel command line set up by boot loader + * 2. spilled registers from the prolog of this function + * => before re-initialising the cache, we must do a purge of the whole + * cache out to memory for safety. As long as nothing is spilled + * during the loop to lines that have already been done, this is safe. + * - RPC + */ + if (ccr & CCR_CACHE_ENABLE) { + unsigned long ways, waysize, addrstart; + + waysize = current_cpu_data.dcache.sets; + +#ifdef CCR_CACHE_ORA + /* + * If the OC is already in RAM mode, we only have + * half of the entries to flush.. + */ + if (ccr & CCR_CACHE_ORA) + waysize >>= 1; +#endif + + waysize <<= current_cpu_data.dcache.entry_shift; + +#ifdef CCR_CACHE_EMODE + /* If EMODE is not set, we only have 1 way to flush. */ + if (!(ccr & CCR_CACHE_EMODE)) + ways = 1; + else +#endif + ways = current_cpu_data.dcache.ways; + + addrstart = CACHE_OC_ADDRESS_ARRAY; + do { + unsigned long addr; + + for (addr = addrstart; + addr < addrstart + waysize; + addr += current_cpu_data.dcache.linesz) + __raw_writel(0, addr); + + addrstart += current_cpu_data.dcache.way_incr; + } while (--ways); + } + + /* + * Default CCR values .. enable the caches + * and invalidate them immediately.. + */ + flags = CCR_CACHE_ENABLE | CCR_CACHE_INVALIDATE; + +#ifdef CCR_CACHE_EMODE + /* Force EMODE if possible */ + if (current_cpu_data.dcache.ways > 1) + flags |= CCR_CACHE_EMODE; + else + flags &= ~CCR_CACHE_EMODE; +#endif + +#if defined(CONFIG_CACHE_WRITETHROUGH) + /* Write-through */ + flags |= CCR_CACHE_WT; +#elif defined(CONFIG_CACHE_WRITEBACK) + /* Write-back */ + flags |= CCR_CACHE_CB; +#else + /* Off */ + flags &= ~CCR_CACHE_ENABLE; +#endif + + l2_cache_init(); + + __raw_writel(flags, SH_CCR); + back_to_cached(); +} +#else +#define cache_init() do { } while (0) +#endif + +#define CSHAPE(totalsize, linesize, assoc) \ + ((totalsize & ~0xff) | (linesize << 4) | assoc) + +#define CACHE_DESC_SHAPE(desc) \ + CSHAPE((desc).way_size * (desc).ways, ilog2((desc).linesz), (desc).ways) + +static void detect_cache_shape(void) +{ + l1d_cache_shape = CACHE_DESC_SHAPE(current_cpu_data.dcache); + + if (current_cpu_data.dcache.flags & SH_CACHE_COMBINED) + l1i_cache_shape = l1d_cache_shape; + else + l1i_cache_shape = CACHE_DESC_SHAPE(current_cpu_data.icache); + + if (current_cpu_data.flags & CPU_HAS_L2_CACHE) + l2_cache_shape = CACHE_DESC_SHAPE(current_cpu_data.scache); + else + l2_cache_shape = -1; /* No S-cache */ +} + +static void fpu_init(void) +{ + /* Disable the FPU */ + if (fpu_disabled && (current_cpu_data.flags & CPU_HAS_FPU)) { + printk("FPU Disabled\n"); + current_cpu_data.flags &= ~CPU_HAS_FPU; + } + + disable_fpu(); + clear_used_math(); +} + +#ifdef CONFIG_SH_DSP +static void release_dsp(void) +{ + unsigned long sr; + + /* Clear SR.DSP bit */ + __asm__ __volatile__ ( + "stc\tsr, %0\n\t" + "and\t%1, %0\n\t" + "ldc\t%0, sr\n\t" + : "=&r" (sr) + : "r" (~SR_DSP) + ); +} + +static void dsp_init(void) +{ + unsigned long sr; + + /* + * Set the SR.DSP bit, wait for one instruction, and then read + * back the SR value. + */ + __asm__ __volatile__ ( + "stc\tsr, %0\n\t" + "or\t%1, %0\n\t" + "ldc\t%0, sr\n\t" + "nop\n\t" + "stc\tsr, %0\n\t" + : "=&r" (sr) + : "r" (SR_DSP) + ); + + /* If the DSP bit is still set, this CPU has a DSP */ + if (sr & SR_DSP) + current_cpu_data.flags |= CPU_HAS_DSP; + + /* Disable the DSP */ + if (dsp_disabled && (current_cpu_data.flags & CPU_HAS_DSP)) { + printk("DSP Disabled\n"); + current_cpu_data.flags &= ~CPU_HAS_DSP; + } + + /* Now that we've determined the DSP status, clear the DSP bit. */ + release_dsp(); +} +#else +static inline void dsp_init(void) { } +#endif /* CONFIG_SH_DSP */ + +/** + * cpu_init + * + * This is our initial entry point for each CPU, and is invoked on the + * boot CPU prior to calling start_kernel(). For SMP, a combination of + * this and start_secondary() will bring up each processor to a ready + * state prior to hand forking the idle loop. + * + * We do all of the basic processor init here, including setting up + * the caches, FPU, DSP, etc. By the time start_kernel() is hit (and + * subsequently platform_setup()) things like determining the CPU + * subtype and initial configuration will all be done. + * + * Each processor family is still responsible for doing its own probing + * and cache configuration in cpu_probe(). + */ +asmlinkage void cpu_init(void) +{ + current_thread_info()->cpu = hard_smp_processor_id(); + + /* First, probe the CPU */ + cpu_probe(); + + if (current_cpu_data.type == CPU_SH_NONE) + panic("Unknown CPU"); + + /* First setup the rest of the I-cache info */ + current_cpu_data.icache.entry_mask = current_cpu_data.icache.way_incr - + current_cpu_data.icache.linesz; + + current_cpu_data.icache.way_size = current_cpu_data.icache.sets * + current_cpu_data.icache.linesz; + + /* And the D-cache too */ + current_cpu_data.dcache.entry_mask = current_cpu_data.dcache.way_incr - + current_cpu_data.dcache.linesz; + + current_cpu_data.dcache.way_size = current_cpu_data.dcache.sets * + current_cpu_data.dcache.linesz; + + /* Init the cache */ + cache_init(); + + if (raw_smp_processor_id() == 0) { +#ifdef CONFIG_MMU + shm_align_mask = max_t(unsigned long, + current_cpu_data.dcache.way_size - 1, + PAGE_SIZE - 1); +#else + shm_align_mask = PAGE_SIZE - 1; +#endif + + /* Boot CPU sets the cache shape */ + detect_cache_shape(); + } + + fpu_init(); + dsp_init(); + + /* + * Initialize the per-CPU ASID cache very early, since the + * TLB flushing routines depend on this being setup. + */ + current_cpu_data.asid_cache = NO_CONTEXT; + + current_cpu_data.phys_bits = __in_29bit_mode() ? 29 : 32; + + speculative_execution_init(); + expmask_init(); + + /* Do the rest of the boot processor setup */ + if (raw_smp_processor_id() == 0) { + /* Save off the BIOS VBR, if there is one */ + sh_bios_vbr_init(); + + /* + * Setup VBR for boot CPU. Secondary CPUs do this through + * start_secondary(). + */ + per_cpu_trap_init(); + + /* + * Boot processor to setup the FP and extended state + * context info. + */ + init_thread_xstate(); + } +} |