diff options
Diffstat (limited to 'arch/powerpc/kernel/misc_32.S')
-rw-r--r-- | arch/powerpc/kernel/misc_32.S | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S new file mode 100644 index 0000000000..2eabb15687 --- /dev/null +++ b/arch/powerpc/kernel/misc_32.S @@ -0,0 +1,390 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * This file contains miscellaneous low-level functions. + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Largely rewritten by Cort Dougan (cort@cs.nmt.edu) + * and Paul Mackerras. + * + */ + +#include <linux/export.h> +#include <linux/sys.h> +#include <asm/unistd.h> +#include <asm/errno.h> +#include <asm/reg.h> +#include <asm/page.h> +#include <asm/cache.h> +#include <asm/cputable.h> +#include <asm/mmu.h> +#include <asm/ppc_asm.h> +#include <asm/thread_info.h> +#include <asm/asm-offsets.h> +#include <asm/processor.h> +#include <asm/bug.h> +#include <asm/ptrace.h> +#include <asm/feature-fixups.h> + + .text + +/* + * This returns the high 64 bits of the product of two 64-bit numbers. + */ +_GLOBAL(mulhdu) + cmpwi r6,0 + cmpwi cr1,r3,0 + mr r10,r4 + mulhwu r4,r4,r5 + beq 1f + mulhwu r0,r10,r6 + mullw r7,r10,r5 + addc r7,r0,r7 + addze r4,r4 +1: beqlr cr1 /* all done if high part of A is 0 */ + mullw r9,r3,r5 + mulhwu r10,r3,r5 + beq 2f + mullw r0,r3,r6 + mulhwu r8,r3,r6 + addc r7,r0,r7 + adde r4,r4,r8 + addze r10,r10 +2: addc r4,r4,r9 + addze r3,r10 + blr + +/* + * reloc_got2 runs through the .got2 section adding an offset + * to each entry. + */ +_GLOBAL(reloc_got2) + mflr r11 + lis r7,__got2_start@ha + addi r7,r7,__got2_start@l + lis r8,__got2_end@ha + addi r8,r8,__got2_end@l + subf r8,r7,r8 + srwi. r8,r8,2 + beqlr + mtctr r8 + bcl 20,31,$+4 +1: mflr r0 + lis r4,1b@ha + addi r4,r4,1b@l + subf r0,r4,r0 + add r7,r0,r7 +2: lwz r0,0(r7) + add r0,r0,r3 + stw r0,0(r7) + addi r7,r7,4 + bdnz 2b + mtlr r11 + blr + +/* + * call_setup_cpu - call the setup_cpu function for this cpu + * r3 = data offset, r24 = cpu number + * + * Setup function is called with: + * r3 = data offset + * r4 = ptr to CPU spec (relocated) + */ +_GLOBAL(call_setup_cpu) + addis r4,r3,cur_cpu_spec@ha + addi r4,r4,cur_cpu_spec@l + lwz r4,0(r4) + add r4,r4,r3 + lwz r5,CPU_SPEC_SETUP(r4) + cmpwi 0,r5,0 + add r5,r5,r3 + beqlr + mtctr r5 + bctr + +#if defined(CONFIG_CPU_FREQ_PMAC) && defined(CONFIG_PPC_BOOK3S_32) + +/* This gets called by via-pmu.c to switch the PLL selection + * on 750fx CPU. This function should really be moved to some + * other place (as most of the cpufreq code in via-pmu + */ +_GLOBAL(low_choose_750fx_pll) + /* Clear MSR:EE */ + mfmsr r7 + rlwinm r0,r7,0,17,15 + mtmsr r0 + + /* If switching to PLL1, disable HID0:BTIC */ + cmplwi cr0,r3,0 + beq 1f + mfspr r5,SPRN_HID0 + rlwinm r5,r5,0,27,25 + sync + mtspr SPRN_HID0,r5 + isync + sync + +1: + /* Calc new HID1 value */ + mfspr r4,SPRN_HID1 /* Build a HID1:PS bit from parameter */ + rlwinm r5,r3,16,15,15 /* Clear out HID1:PS from value read */ + rlwinm r4,r4,0,16,14 /* Could have I used rlwimi here ? */ + or r4,r4,r5 + mtspr SPRN_HID1,r4 + +#ifdef CONFIG_SMP + /* Store new HID1 image */ + lwz r6,TASK_CPU(r2) + slwi r6,r6,2 +#else + li r6, 0 +#endif + addis r6,r6,nap_save_hid1@ha + stw r4,nap_save_hid1@l(r6) + + /* If switching to PLL0, enable HID0:BTIC */ + cmplwi cr0,r3,0 + bne 1f + mfspr r5,SPRN_HID0 + ori r5,r5,HID0_BTIC + sync + mtspr SPRN_HID0,r5 + isync + sync + +1: + /* Return */ + mtmsr r7 + blr + +_GLOBAL(low_choose_7447a_dfs) + /* Clear MSR:EE */ + mfmsr r7 + rlwinm r0,r7,0,17,15 + mtmsr r0 + + /* Calc new HID1 value */ + mfspr r4,SPRN_HID1 + insrwi r4,r3,1,9 /* insert parameter into bit 9 */ + sync + mtspr SPRN_HID1,r4 + sync + isync + + /* Return */ + mtmsr r7 + blr + +#endif /* CONFIG_CPU_FREQ_PMAC && CONFIG_PPC_BOOK3S_32 */ + +#ifdef CONFIG_40x + +/* + * Do an IO access in real mode + */ +_GLOBAL(real_readb) + mfmsr r7 + rlwinm r0,r7,0,~MSR_DR + sync + mtmsr r0 + sync + isync + lbz r3,0(r3) + sync + mtmsr r7 + sync + isync + blr +_ASM_NOKPROBE_SYMBOL(real_readb) + + /* + * Do an IO access in real mode + */ +_GLOBAL(real_writeb) + mfmsr r7 + rlwinm r0,r7,0,~MSR_DR + sync + mtmsr r0 + sync + isync + stb r3,0(r4) + sync + mtmsr r7 + sync + isync + blr +_ASM_NOKPROBE_SYMBOL(real_writeb) + +#endif /* CONFIG_40x */ + +/* + * Copy a whole page. We use the dcbz instruction on the destination + * to reduce memory traffic (it eliminates the unnecessary reads of + * the destination into cache). This requires that the destination + * is cacheable. + */ +#define COPY_16_BYTES \ + lwz r6,4(r4); \ + lwz r7,8(r4); \ + lwz r8,12(r4); \ + lwzu r9,16(r4); \ + stw r6,4(r3); \ + stw r7,8(r3); \ + stw r8,12(r3); \ + stwu r9,16(r3) + +_GLOBAL(copy_page) + rlwinm r5, r3, 0, L1_CACHE_BYTES - 1 + addi r3,r3,-4 + +0: twnei r5, 0 /* WARN if r3 is not cache aligned */ + EMIT_WARN_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING + + addi r4,r4,-4 + + li r5,4 + +#if MAX_COPY_PREFETCH > 1 + li r0,MAX_COPY_PREFETCH + li r11,4 + mtctr r0 +11: dcbt r11,r4 + addi r11,r11,L1_CACHE_BYTES + bdnz 11b +#else /* MAX_COPY_PREFETCH == 1 */ + dcbt r5,r4 + li r11,L1_CACHE_BYTES+4 +#endif /* MAX_COPY_PREFETCH */ + li r0,PAGE_SIZE/L1_CACHE_BYTES - MAX_COPY_PREFETCH + crclr 4*cr0+eq +2: + mtctr r0 +1: + dcbt r11,r4 + dcbz r5,r3 + COPY_16_BYTES +#if L1_CACHE_BYTES >= 32 + COPY_16_BYTES +#if L1_CACHE_BYTES >= 64 + COPY_16_BYTES + COPY_16_BYTES +#if L1_CACHE_BYTES >= 128 + COPY_16_BYTES + COPY_16_BYTES + COPY_16_BYTES + COPY_16_BYTES +#endif +#endif +#endif + bdnz 1b + beqlr + crnot 4*cr0+eq,4*cr0+eq + li r0,MAX_COPY_PREFETCH + li r11,4 + b 2b +EXPORT_SYMBOL(copy_page) + +/* + * Extended precision shifts. + * + * Updated to be valid for shift counts from 0 to 63 inclusive. + * -- Gabriel + * + * R3/R4 has 64 bit value + * R5 has shift count + * result in R3/R4 + * + * ashrdi3: arithmetic right shift (sign propagation) + * lshrdi3: logical right shift + * ashldi3: left shift + */ +_GLOBAL(__ashrdi3) + subfic r6,r5,32 + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count + addi r7,r5,32 # could be xori, or addi with -32 + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) + rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0 + sraw r7,r3,r7 # t2 = MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2 + sraw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr +EXPORT_SYMBOL(__ashrdi3) + +_GLOBAL(__ashldi3) + subfic r6,r5,32 + slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count + addi r7,r5,32 # could be xori, or addi with -32 + srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count) + slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32) + or r3,r3,r6 # MSW |= t1 + slw r4,r4,r5 # LSW = LSW << count + or r3,r3,r7 # MSW |= t2 + blr +EXPORT_SYMBOL(__ashldi3) + +_GLOBAL(__lshrdi3) + subfic r6,r5,32 + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count + addi r7,r5,32 # could be xori, or addi with -32 + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) + srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + srw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr +EXPORT_SYMBOL(__lshrdi3) + +/* + * 64-bit comparison: __cmpdi2(s64 a, s64 b) + * Returns 0 if a < b, 1 if a == b, 2 if a > b. + */ +_GLOBAL(__cmpdi2) + cmpw r3,r5 + li r3,1 + bne 1f + cmplw r4,r6 + beqlr +1: li r3,0 + bltlr + li r3,2 + blr +EXPORT_SYMBOL(__cmpdi2) +/* + * 64-bit comparison: __ucmpdi2(u64 a, u64 b) + * Returns 0 if a < b, 1 if a == b, 2 if a > b. + */ +_GLOBAL(__ucmpdi2) + cmplw r3,r5 + li r3,1 + bne 1f + cmplw r4,r6 + beqlr +1: li r3,0 + bltlr + li r3,2 + blr +EXPORT_SYMBOL(__ucmpdi2) + +_GLOBAL(__bswapdi2) + rotlwi r9,r4,8 + rotlwi r10,r3,8 + rlwimi r9,r4,24,0,7 + rlwimi r10,r3,24,0,7 + rlwimi r9,r4,24,16,23 + rlwimi r10,r3,24,16,23 + mr r3,r9 + mr r4,r10 + blr +EXPORT_SYMBOL(__bswapdi2) + +#ifdef CONFIG_SMP +_GLOBAL(start_secondary_resume) + /* Reset stack */ + rlwinm r1, r1, 0, 0, 31 - THREAD_SHIFT + addi r1,r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE + li r3,0 + stw r3,0(r1) /* Zero the stack frame pointer */ + bl start_secondary + b . +#endif /* CONFIG_SMP */ |