From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-devel@nongnu.org
Subject: [PULL 27/41] target/arm: Fix has_vfp/has_neon ID reg squashing for M-profile
Date: Tue, 20 Oct 2020 16:56:42 +0100 [thread overview]
Message-ID: <20201020155656.8045-28-peter.maydell@linaro.org> (raw)
In-Reply-To: <20201020155656.8045-1-peter.maydell@linaro.org>
In arm_cpu_realizefn(), if the CPU has VFP or Neon disabled then we
squash the ID register fields so that we don't advertise it to the
guest. This code was written for A-profile and needs some tweaks to
work correctly on M-profile:
* A-profile only fields should not be zeroed on M-profile:
- MVFR0.FPSHVEC,FPTRAP
- MVFR1.SIMDLS,SIMDINT,SIMDSP,SIMDHP
- MVFR2.SIMDMISC
* M-profile only fields should be zeroed on M-profile:
- MVFR1.FP16
In particular, because MVFR1.SIMDHP on A-profile is the same field as
MVFR1.FP16 on M-profile this code was incorrectly disabling FP16
support on an M-profile CPU (where has_neon is always false). This
isn't a visible bug yet because we don't have any M-profile CPUs with
FP16 support, but the change is necessary before we introduce any.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20201019151301.2046-9-peter.maydell@linaro.org
---
target/arm/cpu.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 056319859fb..186ee621a65 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -1429,17 +1429,22 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
u = cpu->isar.mvfr0;
u = FIELD_DP32(u, MVFR0, FPSP, 0);
u = FIELD_DP32(u, MVFR0, FPDP, 0);
- u = FIELD_DP32(u, MVFR0, FPTRAP, 0);
u = FIELD_DP32(u, MVFR0, FPDIVIDE, 0);
u = FIELD_DP32(u, MVFR0, FPSQRT, 0);
- u = FIELD_DP32(u, MVFR0, FPSHVEC, 0);
u = FIELD_DP32(u, MVFR0, FPROUND, 0);
+ if (!arm_feature(env, ARM_FEATURE_M)) {
+ u = FIELD_DP32(u, MVFR0, FPTRAP, 0);
+ u = FIELD_DP32(u, MVFR0, FPSHVEC, 0);
+ }
cpu->isar.mvfr0 = u;
u = cpu->isar.mvfr1;
u = FIELD_DP32(u, MVFR1, FPFTZ, 0);
u = FIELD_DP32(u, MVFR1, FPDNAN, 0);
u = FIELD_DP32(u, MVFR1, FPHP, 0);
+ if (arm_feature(env, ARM_FEATURE_M)) {
+ u = FIELD_DP32(u, MVFR1, FP16, 0);
+ }
cpu->isar.mvfr1 = u;
u = cpu->isar.mvfr2;
@@ -1475,16 +1480,18 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
u = FIELD_DP32(u, ID_ISAR6, FHM, 0);
cpu->isar.id_isar6 = u;
- u = cpu->isar.mvfr1;
- u = FIELD_DP32(u, MVFR1, SIMDLS, 0);
- u = FIELD_DP32(u, MVFR1, SIMDINT, 0);
- u = FIELD_DP32(u, MVFR1, SIMDSP, 0);
- u = FIELD_DP32(u, MVFR1, SIMDHP, 0);
- cpu->isar.mvfr1 = u;
+ if (!arm_feature(env, ARM_FEATURE_M)) {
+ u = cpu->isar.mvfr1;
+ u = FIELD_DP32(u, MVFR1, SIMDLS, 0);
+ u = FIELD_DP32(u, MVFR1, SIMDINT, 0);
+ u = FIELD_DP32(u, MVFR1, SIMDSP, 0);
+ u = FIELD_DP32(u, MVFR1, SIMDHP, 0);
+ cpu->isar.mvfr1 = u;
- u = cpu->isar.mvfr2;
- u = FIELD_DP32(u, MVFR2, SIMDMISC, 0);
- cpu->isar.mvfr2 = u;
+ u = cpu->isar.mvfr2;
+ u = FIELD_DP32(u, MVFR2, SIMDMISC, 0);
+ cpu->isar.mvfr2 = u;
+ }
}
if (!cpu->has_neon && !cpu->has_vfp) {
--
2.20.1
next prev parent reply other threads:[~2020-10-20 16:08 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-20 15:56 [PULL 00/41] target-arm queue Peter Maydell
2020-10-20 15:56 ` [PULL 01/41] target/arm: Fix SMLAD incorrect setting of Q bit Peter Maydell
2020-10-20 15:56 ` [PULL 02/41] target/arm: AArch32 VCVT fixed-point to float is always round-to-nearest Peter Maydell
2020-10-20 15:56 ` [PULL 03/41] hw/arm/strongarm: Fix 'time to transmit a char' unit comment Peter Maydell
2020-10-20 15:56 ` [PULL 04/41] hw/arm: Restrict APEI tables generation to the 'virt' machine Peter Maydell
2020-10-20 15:56 ` [PULL 05/41] hw/timer/bcm2835: Introduce BCM2835_SYSTIMER_COUNT definition Peter Maydell
2020-10-20 15:56 ` [PULL 06/41] hw/timer/bcm2835: Rename variable holding CTRL_STATUS register Peter Maydell
2020-10-20 15:56 ` [PULL 07/41] hw/timer/bcm2835: Support the timer COMPARE registers Peter Maydell
2020-10-20 15:56 ` [PULL 08/41] hw/arm/bcm2835_peripherals: Correctly wire the SYS_timer IRQs Peter Maydell
2020-10-20 15:56 ` [PULL 09/41] accel/tcg: Add tlb_flush_page_bits_by_mmuidx* Peter Maydell
2020-10-20 15:56 ` [PULL 10/41] target/arm: Use tlb_flush_page_bits_by_mmuidx* Peter Maydell
2020-10-20 15:56 ` [PULL 11/41] tests/qtest: Add npcm7xx timer test Peter Maydell
2020-10-20 15:56 ` [PULL 12/41] loads-stores.rst: add footnote that clarifies GETPC usage Peter Maydell
2020-10-20 15:56 ` [PULL 13/41] hw/intc/bcm2835_ic: Trace GPU/CPU IRQ handlers Peter Maydell
2020-10-20 15:56 ` [PULL 14/41] hw/intc/bcm2836_control: Use IRQ definitions instead of magic numbers Peter Maydell
2020-10-20 15:56 ` [PULL 15/41] target/arm: Remove redundant mmu_idx lookup Peter Maydell
2020-10-20 15:56 ` [PULL 16/41] target/arm: Fix reported EL for mte_check_fail Peter Maydell
2020-10-20 15:56 ` [PULL 17/41] target/arm: Ignore HCR_EL2.ATA when {E2H,TGE} != 11 Peter Maydell
2020-10-20 15:56 ` [PULL 18/41] microbit_i2c: Fix coredump when dump-vmstate Peter Maydell
2020-10-20 15:56 ` [PULL 19/41] hw/arm/nseries: Fix loading kernel image on n8x0 machines Peter Maydell
2020-10-20 15:56 ` [PULL 20/41] decodetree: Fix codegen for non-overlapping group inside overlapping group Peter Maydell
2020-10-20 15:56 ` [PULL 21/41] target/arm: Implement v8.1M NOCP handling Peter Maydell
2020-10-20 15:56 ` [PULL 22/41] target/arm: Implement v8.1M conditional-select insns Peter Maydell
2020-10-20 15:56 ` [PULL 23/41] target/arm: Make the t32 insn[25:23]=111 group non-overlapping Peter Maydell
2020-10-20 15:56 ` [PULL 24/41] target/arm: Don't allow BLX imm for M-profile Peter Maydell
2020-10-20 15:56 ` [PULL 25/41] target/arm: Implement v8.1M branch-future insns (as NOPs) Peter Maydell
2020-10-20 15:56 ` [PULL 26/41] target/arm: Implement v8.1M low-overhead-loop instructions Peter Maydell
2020-10-20 15:56 ` Peter Maydell [this message]
2020-10-20 15:56 ` [PULL 28/41] target/arm: Allow M-profile CPUs with FP16 to set FPSCR.FP16 Peter Maydell
2020-10-20 15:56 ` [PULL 29/41] target/arm: Implement FPSCR.LTPSIZE for M-profile LOB extension Peter Maydell
2020-10-20 15:56 ` [PULL 30/41] linux-user/aarch64: Reset btype for signals Peter Maydell
2020-10-20 15:56 ` [PULL 31/41] linux-user: Set PAGE_TARGET_1 for TARGET_PROT_BTI Peter Maydell
2020-10-20 15:56 ` [PULL 32/41] include/elf: Add defines related to GNU property notes for AArch64 Peter Maydell
2020-10-20 15:56 ` [PULL 33/41] linux-user/elfload: Avoid leaking interp_name using GLib memory API Peter Maydell
2020-10-20 15:56 ` [PULL 34/41] linux-user/elfload: Fix coding style in load_elf_image Peter Maydell
2020-10-20 15:56 ` [PULL 35/41] linux-user/elfload: Adjust iteration over phdr Peter Maydell
2020-10-20 15:56 ` [PULL 36/41] linux-user/elfload: Move PT_INTERP detection to first loop Peter Maydell
2020-10-20 15:56 ` [PULL 37/41] linux-user/elfload: Use Error for load_elf_image Peter Maydell
2020-10-20 15:56 ` [PULL 38/41] linux-user/elfload: Use Error for load_elf_interp Peter Maydell
2020-10-20 15:56 ` [PULL 39/41] linux-user/elfload: Parse NT_GNU_PROPERTY_TYPE_0 notes Peter Maydell
2020-10-20 15:56 ` [PULL 40/41] linux-user/elfload: Parse GNU_PROPERTY_AARCH64_FEATURE_1_AND Peter Maydell
2020-10-20 15:56 ` [PULL 41/41] tests/tcg/aarch64: Add bti smoke tests Peter Maydell
2020-10-20 16:36 ` [PULL 00/41] target-arm queue Philippe Mathieu-Daudé
2020-10-20 16:36 ` no-reply
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