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-rw-r--r--arch/powerpc/kernel/misc_32.S435
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diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
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+/* 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/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/export.h>
+#include <asm/feature-fixups.h>
+
+ .text
+
+/*
+ * We store the saved ksp_limit in the unused part
+ * of the STACK_FRAME_OVERHEAD
+ */
+_GLOBAL(call_do_softirq)
+ mflr r0
+ stw r0,4(r1)
+ lwz r10,THREAD+KSP_LIMIT(r2)
+ stw r3, THREAD+KSP_LIMIT(r2)
+ stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
+ mr r1,r3
+ stw r10,8(r1)
+ bl __do_softirq
+ lwz r10,8(r1)
+ lwz r1,0(r1)
+ lwz r0,4(r1)
+ stw r10,THREAD+KSP_LIMIT(r2)
+ mtlr r0
+ blr
+
+/*
+ * void call_do_irq(struct pt_regs *regs, void *sp);
+ */
+_GLOBAL(call_do_irq)
+ mflr r0
+ stw r0,4(r1)
+ lwz r10,THREAD+KSP_LIMIT(r2)
+ stw r4, THREAD+KSP_LIMIT(r2)
+ stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
+ mr r1,r4
+ stw r10,8(r1)
+ bl __do_irq
+ lwz r10,8(r1)
+ lwz r1,0(r1)
+ lwz r0,4(r1)
+ stw r10,THREAD+KSP_LIMIT(r2)
+ mtlr r0
+ blr
+
+/*
+ * 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
+ bl 1f
+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_BUG_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_OVERHEAD
+ li r3,0
+ stw r3,0(r1) /* Zero the stack frame pointer */
+ bl start_secondary
+ b .
+#endif /* CONFIG_SMP */
+
+/*
+ * This routine is just here to keep GCC happy - sigh...
+ */
+_GLOBAL(__main)
+ blr
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