From: Kumar Gala Date: Fri, 24 Aug 2007 21:42:53 +0000 (-0500) Subject: [POWERPC] Handle alignment faults on SPE load/store instructions X-Git-Tag: v2.6.24-rc1~1450^2~249 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=26caeb2ee1924d564e8d8190aa783a569532f81a;p=linux-2.6 [POWERPC] Handle alignment faults on SPE load/store instructions This adds code to handle alignment traps generated by the following SPE (signal processing engine) load/store instructions, by emulating the instruction in the kernel (as is done for other instructions that generate alignment traps): evldd[x] Vector Load Double Word into Double Word [Indexed] evldw[x] Vector Load Double into Two Words [Indexed] evldh[x] Vector Load Double into Four Half Words [Indexed] evlhhesplat[x] Vector Load Half Word into Half Words Even and Splat [Indexed] evlhhousplat[x] Vector Load Half Word into Half Word Odd Unsigned and Splat [Indexed] evlhhossplat[x] Vector Load Half Word into Half Word Odd Signed and Splat [Indexed] evlwhe[x] Vector Load Word into Two Half Words Even [Indexed] evlwhou[x] Vector Load Word into Two Half Words Odd Unsigned (zero-extended) [Indexed] evlwhos[x] Vector Load Word into Two Half Words Odd Signed (with sign extension) [Indexed] evlwwsplat[x] Vector Load Word into Word and Splat [Indexed] evlwhsplat[x] Vector Load Word into Two Half Words and Splat [Indexed] evstdd[x] Vector Store Double of Double [Indexed] evstdw[x] Vector Store Double of Two Words [Indexed] evstdh[x] Vector Store Double of Four Half Words [Indexed] evstwhe[x] Vector Store Word of Two Half Words from Even [Indexed] evstwho[x] Vector Store Word of Two Half Words from Odd [Indexed] evstwwe[x] Vector Store Word of Word from Even [Indexed] evstwwo[x] Vector Store Word of Word from Odd [Indexed] Signed-off-by: Kumar Gala --- diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c index 4c47f9cc0d..e06f75daeb 100644 --- a/arch/powerpc/kernel/align.c +++ b/arch/powerpc/kernel/align.c @@ -46,6 +46,8 @@ struct aligninfo { #define S 0x40 /* single-precision fp or... */ #define SX 0x40 /* ... byte count in XER */ #define HARD 0x80 /* string, stwcx. */ +#define E4 0x40 /* SPE endianness is word */ +#define E8 0x80 /* SPE endianness is double word */ /* DSISR bits reported for a DCBZ instruction: */ #define DCBZ 0x5f /* 8xx/82xx dcbz faults when cache not enabled */ @@ -392,6 +394,248 @@ static int emulate_fp_pair(struct pt_regs *regs, unsigned char __user *addr, return 1; /* exception handled and fixed up */ } +#ifdef CONFIG_SPE + +static struct aligninfo spe_aligninfo[32] = { + { 8, LD+E8 }, /* 0 00 00: evldd[x] */ + { 8, LD+E4 }, /* 0 00 01: evldw[x] */ + { 8, LD }, /* 0 00 10: evldh[x] */ + INVALID, /* 0 00 11 */ + { 2, LD }, /* 0 01 00: evlhhesplat[x] */ + INVALID, /* 0 01 01 */ + { 2, LD }, /* 0 01 10: evlhhousplat[x] */ + { 2, LD+SE }, /* 0 01 11: evlhhossplat[x] */ + { 4, LD }, /* 0 10 00: evlwhe[x] */ + INVALID, /* 0 10 01 */ + { 4, LD }, /* 0 10 10: evlwhou[x] */ + { 4, LD+SE }, /* 0 10 11: evlwhos[x] */ + { 4, LD+E4 }, /* 0 11 00: evlwwsplat[x] */ + INVALID, /* 0 11 01 */ + { 4, LD }, /* 0 11 10: evlwhsplat[x] */ + INVALID, /* 0 11 11 */ + + { 8, ST+E8 }, /* 1 00 00: evstdd[x] */ + { 8, ST+E4 }, /* 1 00 01: evstdw[x] */ + { 8, ST }, /* 1 00 10: evstdh[x] */ + INVALID, /* 1 00 11 */ + INVALID, /* 1 01 00 */ + INVALID, /* 1 01 01 */ + INVALID, /* 1 01 10 */ + INVALID, /* 1 01 11 */ + { 4, ST }, /* 1 10 00: evstwhe[x] */ + INVALID, /* 1 10 01 */ + { 4, ST }, /* 1 10 10: evstwho[x] */ + INVALID, /* 1 10 11 */ + { 4, ST+E4 }, /* 1 11 00: evstwwe[x] */ + INVALID, /* 1 11 01 */ + { 4, ST+E4 }, /* 1 11 10: evstwwo[x] */ + INVALID, /* 1 11 11 */ +}; + +#define EVLDD 0x00 +#define EVLDW 0x01 +#define EVLDH 0x02 +#define EVLHHESPLAT 0x04 +#define EVLHHOUSPLAT 0x06 +#define EVLHHOSSPLAT 0x07 +#define EVLWHE 0x08 +#define EVLWHOU 0x0A +#define EVLWHOS 0x0B +#define EVLWWSPLAT 0x0C +#define EVLWHSPLAT 0x0E +#define EVSTDD 0x10 +#define EVSTDW 0x11 +#define EVSTDH 0x12 +#define EVSTWHE 0x18 +#define EVSTWHO 0x1A +#define EVSTWWE 0x1C +#define EVSTWWO 0x1E + +/* + * Emulate SPE loads and stores. + * Only Book-E has these instructions, and it does true little-endian, + * so we don't need the address swizzling. + */ +static int emulate_spe(struct pt_regs *regs, unsigned int reg, + unsigned int instr) +{ + int t, ret; + union { + u64 ll; + u32 w[2]; + u16 h[4]; + u8 v[8]; + } data, temp; + unsigned char __user *p, *addr; + unsigned long *evr = ¤t->thread.evr[reg]; + unsigned int nb, flags; + + instr = (instr >> 1) & 0x1f; + + /* DAR has the operand effective address */ + addr = (unsigned char __user *)regs->dar; + + nb = spe_aligninfo[instr].len; + flags = spe_aligninfo[instr].flags; + + /* Verify the address of the operand */ + if (unlikely(user_mode(regs) && + !access_ok((flags & ST ? VERIFY_WRITE : VERIFY_READ), + addr, nb))) + return -EFAULT; + + /* userland only */ + if (unlikely(!user_mode(regs))) + return 0; + + flush_spe_to_thread(current); + + /* If we are loading, get the data from user space, else + * get it from register values + */ + if (flags & ST) { + data.ll = 0; + switch (instr) { + case EVSTDD: + case EVSTDW: + case EVSTDH: + data.w[0] = *evr; + data.w[1] = regs->gpr[reg]; + break; + case EVSTWHE: + data.h[2] = *evr >> 16; + data.h[3] = regs->gpr[reg] >> 16; + break; + case EVSTWHO: + data.h[2] = *evr & 0xffff; + data.h[3] = regs->gpr[reg] & 0xffff; + break; + case EVSTWWE: + data.w[1] = *evr; + break; + case EVSTWWO: + data.w[1] = regs->gpr[reg]; + break; + default: + return -EINVAL; + } + } else { + temp.ll = data.ll = 0; + ret = 0; + p = addr; + + switch (nb) { + case 8: + ret |= __get_user_inatomic(temp.v[0], p++); + ret |= __get_user_inatomic(temp.v[1], p++); + ret |= __get_user_inatomic(temp.v[2], p++); + ret |= __get_user_inatomic(temp.v[3], p++); + case 4: + ret |= __get_user_inatomic(temp.v[4], p++); + ret |= __get_user_inatomic(temp.v[5], p++); + case 2: + ret |= __get_user_inatomic(temp.v[6], p++); + ret |= __get_user_inatomic(temp.v[7], p++); + if (unlikely(ret)) + return -EFAULT; + } + + switch (instr) { + case EVLDD: + case EVLDW: + case EVLDH: + data.ll = temp.ll; + break; + case EVLHHESPLAT: + data.h[0] = temp.h[3]; + data.h[2] = temp.h[3]; + break; + case EVLHHOUSPLAT: + case EVLHHOSSPLAT: + data.h[1] = temp.h[3]; + data.h[3] = temp.h[3]; + break; + case EVLWHE: + data.h[0] = temp.h[2]; + data.h[2] = temp.h[3]; + break; + case EVLWHOU: + case EVLWHOS: + data.h[1] = temp.h[2]; + data.h[3] = temp.h[3]; + break; + case EVLWWSPLAT: + data.w[0] = temp.w[1]; + data.w[1] = temp.w[1]; + break; + case EVLWHSPLAT: + data.h[0] = temp.h[2]; + data.h[1] = temp.h[2]; + data.h[2] = temp.h[3]; + data.h[3] = temp.h[3]; + break; + default: + return -EINVAL; + } + } + + if (flags & SW) { + switch (flags & 0xf0) { + case E8: + SWAP(data.v[0], data.v[7]); + SWAP(data.v[1], data.v[6]); + SWAP(data.v[2], data.v[5]); + SWAP(data.v[3], data.v[4]); + break; + case E4: + + SWAP(data.v[0], data.v[3]); + SWAP(data.v[1], data.v[2]); + SWAP(data.v[4], data.v[7]); + SWAP(data.v[5], data.v[6]); + break; + /* Its half word endian */ + default: + SWAP(data.v[0], data.v[1]); + SWAP(data.v[2], data.v[3]); + SWAP(data.v[4], data.v[5]); + SWAP(data.v[6], data.v[7]); + break; + } + } + + if (flags & SE) { + data.w[0] = (s16)data.h[1]; + data.w[1] = (s16)data.h[3]; + } + + /* Store result to memory or update registers */ + if (flags & ST) { + ret = 0; + p = addr; + switch (nb) { + case 8: + ret |= __put_user_inatomic(data.v[0], p++); + ret |= __put_user_inatomic(data.v[1], p++); + ret |= __put_user_inatomic(data.v[2], p++); + ret |= __put_user_inatomic(data.v[3], p++); + case 4: + ret |= __put_user_inatomic(data.v[4], p++); + ret |= __put_user_inatomic(data.v[5], p++); + case 2: + ret |= __put_user_inatomic(data.v[6], p++); + ret |= __put_user_inatomic(data.v[7], p++); + } + if (unlikely(ret)) + return -EFAULT; + } else { + *evr = data.w[0]; + regs->gpr[reg] = data.w[1]; + } + + return 1; +} +#endif /* CONFIG_SPE */ /* * Called on alignment exception. Attempts to fixup @@ -450,6 +694,12 @@ int fix_alignment(struct pt_regs *regs) /* extract the operation and registers from the dsisr */ reg = (dsisr >> 5) & 0x1f; /* source/dest register */ areg = dsisr & 0x1f; /* register to update */ + +#ifdef CONFIG_SPE + if ((instr >> 26) == 0x4) + return emulate_spe(regs, reg, instr); +#endif + instr = (dsisr >> 10) & 0x7f; instr |= (dsisr >> 13) & 0x60;