From: David Gibson <david@gibson.dropbear.id.au>
To: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Warren <ivan@vmfacility.fr>,
qemu-ppc@nongnu.org, qemu-devel@nongnu.org
Subject: Re: [PATCH v5 02/10] target/ppc: Disconnect hflags from MSR
Date: Wed, 24 Mar 2021 11:03:02 +1100 [thread overview]
Message-ID: <YFqBtsijRRcEBB/k@yekko.fritz.box> (raw)
In-Reply-To: <20210323184340.619757-3-richard.henderson@linaro.org>
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On Tue, Mar 23, 2021 at 12:43:32PM -0600, Richard Henderson wrote:
> Copying flags directly from msr has drawbacks: (1) msr bits
> mean different things per cpu, (2) msr has 64 bits on 64 cpus
> while tb->flags has only 32 bits.
>
> Create a enum to define these bits. Document the origin of each bit
> and validate those bits that must match MSR. This fixes the
> truncation of env->hflags to tb->flags, because we no longer
> have hflags bits set above bit 31.
>
> Most of the code in ppc_tr_init_disas_context is moved over to
> hreg_compute_hflags. Some of it is simple extractions from msr,
> some requires examining other cpu flags. Anything that is moved
> becomes a simple extract from hflags in ppc_tr_init_disas_context.
>
> Several existing bugs are left in ppc_tr_init_disas_context, where
> additional changes are required -- to be addressed in future patches.
>
> Remove a broken #if 0 block.
>
> Reported-by: Ivan Warren <ivan@vmfacility.fr>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Applied to ppc-for-6.0.
> ---
> target/ppc/cpu.h | 25 ++++++++++++++++
> target/ppc/helper_regs.c | 65 +++++++++++++++++++++++++++++++++-------
> target/ppc/translate.c | 55 ++++++++++------------------------
> 3 files changed, 95 insertions(+), 50 deletions(-)
>
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index fd13489dce..fe6c3f815d 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -585,6 +585,31 @@ enum {
> POWERPC_FLAG_HID0_LE = 0x00400000,
> };
>
> +/*
> + * Bits for env->hflags.
> + *
> + * Most of these bits overlap with corresponding bits in MSR,
> + * but some come from other sources. Those that do come from
> + * the MSR are validated in hreg_compute_hflags.
> + */
> +enum {
> + HFLAGS_LE = 0, /* MSR_LE -- comes from elsewhere on 601 */
> + HFLAGS_HV = 1, /* computed from MSR_HV and other state */
> + HFLAGS_64 = 2, /* computed from MSR_CE and MSR_SF */
> + HFLAGS_DR = 4, /* MSR_DR */
> + HFLAGS_IR = 5, /* MSR_IR */
> + HFLAGS_SPE = 6, /* from MSR_SPE if cpu has SPE; avoid overlap w/ MSR_VR */
> + HFLAGS_VSX = 7, /* from MSR_VSX if cpu has VSX; avoid overlap w/ MSR_AP */
> + HFLAGS_TM = 8, /* computed from MSR_TM */
> + HFLAGS_BE = 9, /* MSR_BE -- from elsewhere on embedded ppc */
> + HFLAGS_SE = 10, /* MSR_SE -- from elsewhere on embedded ppc */
> + HFLAGS_FP = 13, /* MSR_FP */
> + HFLAGS_PR = 14, /* MSR_PR */
> + HFLAGS_SA = 22, /* MSR_SA */
> + HFLAGS_AP = 23, /* MSR_AP */
> + HFLAGS_VR = 25, /* MSR_VR if cpu has VRE */
> +};
> +
> /*****************************************************************************/
> /* Floating point status and control register */
> #define FPSCR_DRN2 34 /* Decimal Floating-Point rounding control */
> diff --git a/target/ppc/helper_regs.c b/target/ppc/helper_regs.c
> index a87e354ca2..df9673b90f 100644
> --- a/target/ppc/helper_regs.c
> +++ b/target/ppc/helper_regs.c
> @@ -18,6 +18,7 @@
> */
>
> #include "qemu/osdep.h"
> +#include "cpu.h"
> #include "qemu/main-loop.h"
> #include "exec/exec-all.h"
> #include "sysemu/kvm.h"
> @@ -87,24 +88,66 @@ void hreg_compute_mem_idx(CPUPPCState *env)
>
> void hreg_compute_hflags(CPUPPCState *env)
> {
> - target_ulong hflags_mask;
> + target_ulong msr = env->msr;
> + uint32_t ppc_flags = env->flags;
> + uint32_t hflags = 0;
> + uint32_t msr_mask;
>
> - /* We 'forget' FE0 & FE1: we'll never generate imprecise exceptions */
> - hflags_mask = (1 << MSR_VR) | (1 << MSR_AP) | (1 << MSR_SA) |
> - (1 << MSR_PR) | (1 << MSR_FP) | (1 << MSR_SE) | (1 << MSR_BE) |
> - (1 << MSR_LE) | (1 << MSR_VSX) | (1 << MSR_IR) | (1 << MSR_DR);
> - hflags_mask |= (1ULL << MSR_CM) | (1ULL << MSR_SF) | MSR_HVB;
> - hreg_compute_mem_idx(env);
> - env->hflags = env->msr & hflags_mask;
> + /* Some bits come straight across from MSR. */
> + QEMU_BUILD_BUG_ON(MSR_LE != HFLAGS_LE);
> + QEMU_BUILD_BUG_ON(MSR_PR != HFLAGS_PR);
> + QEMU_BUILD_BUG_ON(MSR_DR != HFLAGS_DR);
> + QEMU_BUILD_BUG_ON(MSR_IR != HFLAGS_IR);
> + QEMU_BUILD_BUG_ON(MSR_FP != HFLAGS_FP);
> + QEMU_BUILD_BUG_ON(MSR_SA != HFLAGS_SA);
> + QEMU_BUILD_BUG_ON(MSR_AP != HFLAGS_AP);
> + msr_mask = ((1 << MSR_LE) | (1 << MSR_PR) |
> + (1 << MSR_DR) | (1 << MSR_IR) |
> + (1 << MSR_FP) | (1 << MSR_SA) | (1 << MSR_AP));
>
> - if (env->flags & POWERPC_FLAG_HID0_LE) {
> + if (ppc_flags & POWERPC_FLAG_HID0_LE) {
> /*
> * Note that MSR_LE is not set in env->msr_mask for this cpu,
> - * and so will never be set in msr or hflags at this point.
> + * and so will never be set in msr.
> */
> uint32_t le = extract32(env->spr[SPR_HID0], 3, 1);
> - env->hflags |= le << MSR_LE;
> + hflags |= le << MSR_LE;
> }
> +
> + if (ppc_flags & POWERPC_FLAG_BE) {
> + QEMU_BUILD_BUG_ON(MSR_BE != HFLAGS_BE);
> + msr_mask |= 1 << MSR_BE;
> + }
> + if (ppc_flags & POWERPC_FLAG_SE) {
> + QEMU_BUILD_BUG_ON(MSR_SE != HFLAGS_SE);
> + msr_mask |= 1 << MSR_SE;
> + }
> +
> + if (msr_is_64bit(env, msr)) {
> + hflags |= 1 << HFLAGS_64;
> + }
> + if ((ppc_flags & POWERPC_FLAG_SPE) && (msr & (1 << MSR_SPE))) {
> + hflags |= 1 << HFLAGS_SPE;
> + }
> + if (ppc_flags & POWERPC_FLAG_VRE) {
> + QEMU_BUILD_BUG_ON(MSR_VR != HFLAGS_VR);
> + msr_mask |= 1 << MSR_VR;
> + }
> + if ((ppc_flags & POWERPC_FLAG_VSX) && (msr & (1 << MSR_VSX))) {
> + hflags |= 1 << HFLAGS_VSX;
> + }
> + if ((ppc_flags & POWERPC_FLAG_TM) && (msr & (1ull << MSR_TM))) {
> + hflags |= 1 << HFLAGS_TM;
> + }
> +
> +#ifndef CONFIG_USER_ONLY
> + if (!env->has_hv_mode || (msr & (1ull << MSR_HV))) {
> + hflags |= 1 << HFLAGS_HV;
> + }
> +#endif
> +
> + env->hflags = hflags | (msr & msr_mask);
> + hreg_compute_mem_idx(env);
> }
>
> void cpu_interrupt_exittb(CPUState *cs)
> diff --git a/target/ppc/translate.c b/target/ppc/translate.c
> index 0984ce637b..a9325a12e5 100644
> --- a/target/ppc/translate.c
> +++ b/target/ppc/translate.c
> @@ -7879,67 +7879,48 @@ static void ppc_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
> {
> DisasContext *ctx = container_of(dcbase, DisasContext, base);
> CPUPPCState *env = cs->env_ptr;
> + uint32_t hflags = ctx->base.tb->flags;
> int bound;
>
> ctx->exception = POWERPC_EXCP_NONE;
> ctx->spr_cb = env->spr_cb;
> - ctx->pr = msr_pr;
> + ctx->pr = (hflags >> HFLAGS_PR) & 1;
> ctx->mem_idx = env->dmmu_idx;
> - ctx->dr = msr_dr;
> -#if !defined(CONFIG_USER_ONLY)
> - ctx->hv = msr_hv || !env->has_hv_mode;
> -#endif
> + ctx->dr = (hflags >> HFLAGS_DR) & 1;
> + ctx->hv = (hflags >> HFLAGS_HV) & 1;
> ctx->insns_flags = env->insns_flags;
> ctx->insns_flags2 = env->insns_flags2;
> ctx->access_type = -1;
> ctx->need_access_type = !mmu_is_64bit(env->mmu_model);
> - ctx->le_mode = !!(env->hflags & (1 << MSR_LE));
> + ctx->le_mode = (hflags >> HFLAGS_LE) & 1;
> ctx->default_tcg_memop_mask = ctx->le_mode ? MO_LE : MO_BE;
> ctx->flags = env->flags;
> #if defined(TARGET_PPC64)
> - ctx->sf_mode = msr_is_64bit(env, env->msr);
> + ctx->sf_mode = (hflags >> HFLAGS_64) & 1;
> ctx->has_cfar = !!(env->flags & POWERPC_FLAG_CFAR);
> #endif
> ctx->lazy_tlb_flush = env->mmu_model == POWERPC_MMU_32B
> || env->mmu_model == POWERPC_MMU_601
> || env->mmu_model & POWERPC_MMU_64;
>
> - ctx->fpu_enabled = !!msr_fp;
> - if ((env->flags & POWERPC_FLAG_SPE) && msr_spe) {
> - ctx->spe_enabled = !!msr_spe;
> - } else {
> - ctx->spe_enabled = false;
> - }
> - if ((env->flags & POWERPC_FLAG_VRE) && msr_vr) {
> - ctx->altivec_enabled = !!msr_vr;
> - } else {
> - ctx->altivec_enabled = false;
> - }
> - if ((env->flags & POWERPC_FLAG_VSX) && msr_vsx) {
> - ctx->vsx_enabled = !!msr_vsx;
> - } else {
> - ctx->vsx_enabled = false;
> - }
> + ctx->fpu_enabled = (hflags >> HFLAGS_FP) & 1;
> + ctx->spe_enabled = (hflags >> HFLAGS_SPE) & 1;
> + ctx->altivec_enabled = (hflags >> HFLAGS_VR) & 1;
> + ctx->vsx_enabled = (hflags >> HFLAGS_VSX) & 1;
> if ((env->flags & POWERPC_FLAG_SCV)
> && (env->spr[SPR_FSCR] & (1ull << FSCR_SCV))) {
> ctx->scv_enabled = true;
> } else {
> ctx->scv_enabled = false;
> }
> -#if defined(TARGET_PPC64)
> - if ((env->flags & POWERPC_FLAG_TM) && msr_tm) {
> - ctx->tm_enabled = !!msr_tm;
> - } else {
> - ctx->tm_enabled = false;
> - }
> -#endif
> + ctx->tm_enabled = (hflags >> HFLAGS_TM) & 1;
> ctx->gtse = !!(env->spr[SPR_LPCR] & LPCR_GTSE);
> - if ((env->flags & POWERPC_FLAG_SE) && msr_se) {
> - ctx->singlestep_enabled = CPU_SINGLE_STEP;
> - } else {
> - ctx->singlestep_enabled = 0;
> +
> + ctx->singlestep_enabled = 0;
> + if ((hflags >> HFLAGS_SE) & 1) {
> + ctx->singlestep_enabled |= CPU_SINGLE_STEP;
> }
> - if ((env->flags & POWERPC_FLAG_BE) && msr_be) {
> + if ((hflags >> HFLAGS_BE) & 1) {
> ctx->singlestep_enabled |= CPU_BRANCH_STEP;
> }
> if ((env->flags & POWERPC_FLAG_DE) && msr_de) {
> @@ -7956,10 +7937,6 @@ static void ppc_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
> if (unlikely(ctx->base.singlestep_enabled)) {
> ctx->singlestep_enabled |= GDBSTUB_SINGLE_STEP;
> }
> -#if defined(DO_SINGLE_STEP) && 0
> - /* Single step trace mode */
> - msr_se = 1;
> -#endif
>
> bound = -(ctx->base.pc_first | TARGET_PAGE_MASK) / 4;
> ctx->base.max_insns = MIN(ctx->base.max_insns, bound);
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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next prev parent reply other threads:[~2021-03-24 1:36 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-23 18:43 [PATCH v5 00/10] target/ppc: Fix truncation of env->hflags Richard Henderson
2021-03-23 18:43 ` [PATCH v5 01/10] target/ppc: Extract post_load_update_msr Richard Henderson
2021-03-24 0:00 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 02/10] target/ppc: Disconnect hflags from MSR Richard Henderson
2021-03-24 0:03 ` David Gibson [this message]
2021-03-29 13:05 ` Greg Kurz
2021-03-29 16:26 ` Richard Henderson
2021-03-30 4:54 ` David Gibson
2021-03-30 15:01 ` Richard Henderson
2021-03-31 0:09 ` David Gibson
2021-03-31 4:04 ` Greg Kurz
2021-03-31 4:47 ` David Gibson
2021-03-31 6:31 ` Richard Henderson
2021-04-01 3:17 ` David Gibson
2021-03-31 7:30 ` Greg Kurz
2021-03-23 18:43 ` [PATCH v5 03/10] target/ppc: Reduce env->hflags to uint32_t Richard Henderson
2021-03-24 0:03 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 04/10] target/ppc: Put dbcr0 single-step bits into hflags Richard Henderson
2021-03-24 0:04 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 05/10] target/ppc: Create helper_scv Richard Henderson
2021-03-24 0:05 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 06/10] target/ppc: Put LPCR[GTSE] in hflags Richard Henderson
2021-03-24 0:06 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 07/10] target/ppc: Remove MSR_SA and MSR_AP from hflags Richard Henderson
2021-03-24 0:08 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 08/10] target/ppc: Remove env->immu_idx and env->dmmu_idx Richard Henderson
2021-03-24 0:09 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 09/10] linux-user/ppc: Fix msr updates for signal handling Richard Henderson
2021-03-24 0:10 ` David Gibson
2021-03-23 18:43 ` [PATCH v5 10/10] target/ppc: Validate hflags with CONFIG_DEBUG_TCG Richard Henderson
2021-03-24 0:12 ` David Gibson
2021-03-25 8:47 ` David Gibson
2021-03-26 12:41 ` Richard Henderson
2021-03-27 12:46 ` Richard Henderson
2021-03-28 13:09 ` David Gibson
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