diff mbox series

[Stable-8.0.4,34/63] target/loongarch: Fix the CSRRD CPUID instruction on big endian hosts

Message ID 20230804191647.1875608-3-mjt@tls.msk.ru
State New
Headers show
Series Patch Round-up for stable 8.0.4, freeze on 2023-08-05 | expand

Commit Message

Michael Tokarev Aug. 4, 2023, 7:16 p.m. UTC 
From: Thomas Huth <thuth@redhat.com>

The test in tests/avocado/machine_loongarch.py is currently failing
on big endian hosts like s390x. By comparing the traces between running
the QEMU_EFI.fd bios on a s390x and on a x86 host, it's quickly obvious
that the CSRRD instruction for the CPUID is behaving differently. And
indeed: The code currently does a long read (i.e. 64 bit) from the
address that points to the CPUState->cpu_index field (with tcg_gen_ld_tl()
in the trans_csrrd() function). But this cpu_index field is only an "int"
(i.e. 32 bit). While this dirty pointer magic works on little endian hosts,
it of course fails on big endian hosts. Fix it by using a proper helper
function instead.

Message-Id: <20230720175307.854460-1-thuth@redhat.com>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Thomas Huth <thuth@redhat.com>
(cherry picked from commit c34ad459926f6c600a55fe6782a27edfa405d60b)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
diff mbox series

Patch

diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index e11c875188..4bf453e002 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -319,6 +319,7 @@  typedef struct CPUArchState {
     uint64_t CSR_DBG;
     uint64_t CSR_DERA;
     uint64_t CSR_DSAVE;
+    uint64_t CSR_CPUID;
 
 #ifndef CONFIG_USER_ONLY
     LoongArchTLB  tlb[LOONGARCH_TLB_MAX];
diff --git a/target/loongarch/csr_helper.c b/target/loongarch/csr_helper.c
index 7e02787895..b778e6952d 100644
--- a/target/loongarch/csr_helper.c
+++ b/target/loongarch/csr_helper.c
@@ -36,6 +36,15 @@  target_ulong helper_csrrd_pgd(CPULoongArchState *env)
     return v;
 }
 
+target_ulong helper_csrrd_cpuid(CPULoongArchState *env)
+{
+    LoongArchCPU *lac = env_archcpu(env);
+
+    env->CSR_CPUID = CPU(lac)->cpu_index;
+
+    return env->CSR_CPUID;
+}
+
 target_ulong helper_csrrd_tval(CPULoongArchState *env)
 {
     LoongArchCPU *cpu = env_archcpu(env);
diff --git a/target/loongarch/helper.h b/target/loongarch/helper.h
index 9c01823a26..f47b0f2d05 100644
--- a/target/loongarch/helper.h
+++ b/target/loongarch/helper.h
@@ -98,6 +98,7 @@  DEF_HELPER_1(rdtime_d, i64, env)
 #ifndef CONFIG_USER_ONLY
 /* CSRs helper */
 DEF_HELPER_1(csrrd_pgd, i64, env)
+DEF_HELPER_1(csrrd_cpuid, i64, env)
 DEF_HELPER_1(csrrd_tval, i64, env)
 DEF_HELPER_2(csrwr_estat, i64, env, tl)
 DEF_HELPER_2(csrwr_asid, i64, env, tl)
diff --git a/target/loongarch/insn_trans/trans_privileged.c.inc b/target/loongarch/insn_trans/trans_privileged.c.inc
index 5a04352b01..71d7f37717 100644
--- a/target/loongarch/insn_trans/trans_privileged.c.inc
+++ b/target/loongarch/insn_trans/trans_privileged.c.inc
@@ -99,13 +99,7 @@  static const CSRInfo csr_info[] = {
     CSR_OFF(PWCH),
     CSR_OFF(STLBPS),
     CSR_OFF(RVACFG),
-    [LOONGARCH_CSR_CPUID] = {
-        .offset = (int)offsetof(CPUState, cpu_index)
-                  - (int)offsetof(LoongArchCPU, env),
-        .flags = CSRFL_READONLY,
-        .readfn = NULL,
-        .writefn = NULL
-    },
+    CSR_OFF_FUNCS(CPUID, CSRFL_READONLY, gen_helper_csrrd_cpuid, NULL),
     CSR_OFF_FLAGS(PRCFG1, CSRFL_READONLY),
     CSR_OFF_FLAGS(PRCFG2, CSRFL_READONLY),
     CSR_OFF_FLAGS(PRCFG3, CSRFL_READONLY),