linux/arch/powerpc/kernel/ppc_ksyms.c
Philippe Bergheaud 00f554fade powerpc: memcpy optimization for 64bit LE
Unaligned stores take alignment exceptions on POWER7 running in little-endian.
This is a dumb little-endian base memcpy that prevents unaligned stores.
Once booted the feature fixup code switches over to the VMX copy loops
(which are already endian safe).

The question is what we do before that switch over. The base 64bit
memcpy takes alignment exceptions on POWER7 so we can't use it as is.
Fixing the causes of alignment exception would slow it down, because
we'd need to ensure all loads and stores are aligned either through
rotate tricks or bytewise loads and stores. Either would be bad for
all other 64bit platforms.

[ I simplified the loop a bit - Anton ]

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-30 15:26:18 +10:00

210 lines
5.0 KiB
C

#include <linux/export.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/sched.h>
#include <linux/elfcore.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/screen_info.h>
#include <linux/vt_kern.h>
#include <linux/nvram.h>
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/bitops.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <linux/atomic.h>
#include <asm/checksum.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/pmu.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/irq.h>
#include <asm/pmac_feature.h>
#include <asm/dma.h>
#include <asm/machdep.h>
#include <asm/hw_irq.h>
#include <asm/nvram.h>
#include <asm/mmu_context.h>
#include <asm/backlight.h>
#include <asm/time.h>
#include <asm/cputable.h>
#include <asm/btext.h>
#include <asm/div64.h>
#include <asm/signal.h>
#include <asm/dcr.h>
#include <asm/ftrace.h>
#include <asm/switch_to.h>
#include <asm/epapr_hcalls.h>
#ifdef CONFIG_PPC32
extern void transfer_to_handler(void);
extern void do_IRQ(struct pt_regs *regs);
extern void machine_check_exception(struct pt_regs *regs);
extern void alignment_exception(struct pt_regs *regs);
extern void program_check_exception(struct pt_regs *regs);
extern void single_step_exception(struct pt_regs *regs);
extern int sys_sigreturn(struct pt_regs *regs);
EXPORT_SYMBOL(clear_pages);
EXPORT_SYMBOL(ISA_DMA_THRESHOLD);
EXPORT_SYMBOL(DMA_MODE_READ);
EXPORT_SYMBOL(DMA_MODE_WRITE);
EXPORT_SYMBOL(transfer_to_handler);
EXPORT_SYMBOL(do_IRQ);
EXPORT_SYMBOL(machine_check_exception);
EXPORT_SYMBOL(alignment_exception);
EXPORT_SYMBOL(program_check_exception);
EXPORT_SYMBOL(single_step_exception);
EXPORT_SYMBOL(sys_sigreturn);
#endif
#ifdef CONFIG_FUNCTION_TRACER
EXPORT_SYMBOL(_mcount);
#endif
EXPORT_SYMBOL(strcpy);
EXPORT_SYMBOL(strncpy);
EXPORT_SYMBOL(strcat);
EXPORT_SYMBOL(strlen);
EXPORT_SYMBOL(strcmp);
EXPORT_SYMBOL(strncmp);
#ifndef CONFIG_GENERIC_CSUM
EXPORT_SYMBOL(csum_partial);
EXPORT_SYMBOL(csum_partial_copy_generic);
EXPORT_SYMBOL(ip_fast_csum);
EXPORT_SYMBOL(csum_tcpudp_magic);
#endif
EXPORT_SYMBOL(__copy_tofrom_user);
EXPORT_SYMBOL(__clear_user);
EXPORT_SYMBOL(copy_page);
#if defined(CONFIG_PCI) && defined(CONFIG_PPC32)
EXPORT_SYMBOL(isa_io_base);
EXPORT_SYMBOL(isa_mem_base);
EXPORT_SYMBOL(pci_dram_offset);
#endif /* CONFIG_PCI */
EXPORT_SYMBOL(start_thread);
#ifdef CONFIG_PPC_FPU
EXPORT_SYMBOL(giveup_fpu);
EXPORT_SYMBOL(load_fp_state);
EXPORT_SYMBOL(store_fp_state);
#endif
#ifdef CONFIG_ALTIVEC
EXPORT_SYMBOL(giveup_altivec);
EXPORT_SYMBOL(load_vr_state);
EXPORT_SYMBOL(store_vr_state);
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_VSX
EXPORT_SYMBOL(giveup_vsx);
EXPORT_SYMBOL_GPL(__giveup_vsx);
#endif /* CONFIG_VSX */
#ifdef CONFIG_SPE
EXPORT_SYMBOL(giveup_spe);
#endif /* CONFIG_SPE */
#ifndef CONFIG_PPC64
EXPORT_SYMBOL(flush_instruction_cache);
#endif
EXPORT_SYMBOL(flush_dcache_range);
EXPORT_SYMBOL(flush_icache_range);
#ifdef CONFIG_SMP
#ifdef CONFIG_PPC32
EXPORT_SYMBOL(smp_hw_index);
#endif
#endif
#ifdef CONFIG_ADB
EXPORT_SYMBOL(adb_request);
EXPORT_SYMBOL(adb_register);
EXPORT_SYMBOL(adb_unregister);
EXPORT_SYMBOL(adb_poll);
EXPORT_SYMBOL(adb_try_handler_change);
#endif /* CONFIG_ADB */
#ifdef CONFIG_ADB_CUDA
EXPORT_SYMBOL(cuda_request);
EXPORT_SYMBOL(cuda_poll);
#endif /* CONFIG_ADB_CUDA */
EXPORT_SYMBOL(to_tm);
#ifdef CONFIG_PPC32
long long __ashrdi3(long long, int);
long long __ashldi3(long long, int);
long long __lshrdi3(long long, int);
EXPORT_SYMBOL(__ashrdi3);
EXPORT_SYMBOL(__ashldi3);
EXPORT_SYMBOL(__lshrdi3);
int __ucmpdi2(unsigned long long, unsigned long long);
EXPORT_SYMBOL(__ucmpdi2);
int __cmpdi2(long long, long long);
EXPORT_SYMBOL(__cmpdi2);
#endif
long long __bswapdi2(long long);
EXPORT_SYMBOL(__bswapdi2);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(memcmp);
EXPORT_SYMBOL(memchr);
#if defined(CONFIG_FB_VGA16_MODULE)
EXPORT_SYMBOL(screen_info);
#endif
#ifdef CONFIG_PPC32
EXPORT_SYMBOL(timer_interrupt);
EXPORT_SYMBOL(tb_ticks_per_jiffy);
EXPORT_SYMBOL(cacheable_memcpy);
EXPORT_SYMBOL(cacheable_memzero);
#endif
#ifdef CONFIG_PPC32
EXPORT_SYMBOL(switch_mmu_context);
#endif
#ifdef CONFIG_PPC_STD_MMU_32
extern long mol_trampoline;
EXPORT_SYMBOL(mol_trampoline); /* For MOL */
EXPORT_SYMBOL(flush_hash_pages); /* For MOL */
#ifdef CONFIG_SMP
extern int mmu_hash_lock;
EXPORT_SYMBOL(mmu_hash_lock); /* For MOL */
#endif /* CONFIG_SMP */
extern long *intercept_table;
EXPORT_SYMBOL(intercept_table);
#endif /* CONFIG_PPC_STD_MMU_32 */
#ifdef CONFIG_PPC_DCR_NATIVE
EXPORT_SYMBOL(__mtdcr);
EXPORT_SYMBOL(__mfdcr);
#endif
EXPORT_SYMBOL(empty_zero_page);
#ifdef CONFIG_PPC64
EXPORT_SYMBOL(__arch_hweight8);
EXPORT_SYMBOL(__arch_hweight16);
EXPORT_SYMBOL(__arch_hweight32);
EXPORT_SYMBOL(__arch_hweight64);
#endif
#ifdef CONFIG_PPC_BOOK3S_64
EXPORT_SYMBOL_GPL(mmu_psize_defs);
#endif
#ifdef CONFIG_EPAPR_PARAVIRT
EXPORT_SYMBOL(epapr_hypercall_start);
#endif