[PATCH v2 0/6] linux-user: Rework get_elf_hwcap() and support MIPS Loongson 2F/3E

[PATCH v2 0/6] linux-user: Rework get_elf_hwcap() and support MIPS Loongson 2F/3E

[Philippe Mathieu-Daudé]

Introduce the GET_FEATURE_REG_SET() and GET_FEATURE_REG_EQU()
macros to check if an instruction set is supported by a CPU
using CP0 read-only bits (instead of QEMU insn_flags which
is not always coherent - we might remove it soon).

Use these macros to test for MSA ASE and Release 6.

Update the ELF HWCAP bits and set the Loongson instructions
so we can run 2F/3E userland binaries.

Supersedes: <20201201083951.2745111-1-f4bug@amsat.org>

Philippe Mathieu-Daudé (6):
  linux-user/elfload: Move GET_FEATURE macro out of get_elf_hwcap() body
  linux-user/elfload: Rename MIPS GET_FEATURE() as GET_FEATURE_INSN()
  linux-user/elfload: Introduce MIPS GET_FEATURE_REG_SET() macro
  linux-user/elfload: Introduce MIPS GET_FEATURE_REG_EQU() macro
  linux-user/elfload: Update HWCAP bits from linux 5.7
  linux-user: Add support for MIPS Loongson 2F/3E

 linux-user/elfload.c | 41 ++++++++++++++++++++++++++++++++++-------
 1 file changed, 34 insertions(+), 7 deletions(-)

-- 
2.26.2

[PATCH v2 1/6] linux-user/elfload: Move GET_FEATURE macro out of get_elf_hwcap() body

[Philippe Mathieu-Daudé]

As we are going to add more macros, keep the function body clear.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 0b02a926025..aae28fd929d 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -989,22 +989,22 @@ enum {
 
 #define ELF_HWCAP get_elf_hwcap()
 
+#define GET_FEATURE(_flag, _hwcap) \
+    do { if (cpu->env.insn_flags & (_flag)) { hwcaps |= _hwcap; } } while (0)
+
 static uint32_t get_elf_hwcap(void)
 {
     MIPSCPU *cpu = MIPS_CPU(thread_cpu);
     uint32_t hwcaps = 0;
 
-#define GET_FEATURE(flag, hwcap) \
-    do { if (cpu->env.insn_flags & (flag)) { hwcaps |= hwcap; } } while (0)
-
     GET_FEATURE(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
     GET_FEATURE(ASE_MSA, HWCAP_MIPS_MSA);
 
-#undef GET_FEATURE
-
     return hwcaps;
 }
 
+#undef GET_FEATURE
+
 #endif /* TARGET_MIPS */
 
 #ifdef TARGET_MICROBLAZE
-- 
2.26.2

Re: [PATCH v2 1/6] linux-user/elfload: Move GET_FEATURE macro out of get_elf_hwcap() body

[Richard Henderson]

On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
> As we are going to add more macros, keep the function body clear.
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  linux-user/elfload.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~

[PATCH v2 2/6] linux-user/elfload: Rename MIPS GET_FEATURE() as GET_FEATURE_INSN()

[Philippe Mathieu-Daudé]

We want to add macros similar to GET_FEATURE().
As this one use the 'insn_flags' field, rename it
GET_FEATURE_INSN().

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index aae28fd929d..0e1d7e7677c 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -989,7 +989,7 @@ enum {
 
 #define ELF_HWCAP get_elf_hwcap()
 
-#define GET_FEATURE(_flag, _hwcap) \
+#define GET_FEATURE_INSN(_flag, _hwcap) \
     do { if (cpu->env.insn_flags & (_flag)) { hwcaps |= _hwcap; } } while (0)
 
 static uint32_t get_elf_hwcap(void)
@@ -997,13 +997,13 @@ static uint32_t get_elf_hwcap(void)
     MIPSCPU *cpu = MIPS_CPU(thread_cpu);
     uint32_t hwcaps = 0;
 
-    GET_FEATURE(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
-    GET_FEATURE(ASE_MSA, HWCAP_MIPS_MSA);
+    GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
+    GET_FEATURE_INSN(ASE_MSA, HWCAP_MIPS_MSA);
 
     return hwcaps;
 }
 
-#undef GET_FEATURE
+#undef GET_FEATURE_INSN
 
 #endif /* TARGET_MIPS */
 
-- 
2.26.2

Re: [PATCH v2 2/6] linux-user/elfload: Rename MIPS GET_FEATURE() as GET_FEATURE_INSN()

[Richard Henderson]

On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
> We want to add macros similar to GET_FEATURE().
> As this one use the 'insn_flags' field, rename it
> GET_FEATURE_INSN().
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  linux-user/elfload.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~

[PATCH v2 3/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_SET() macro

[Philippe Mathieu-Daudé]

ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_SET() macro which
checks if a CPU register has bits set.

Use the macro to check for MSA (which sets the MSAP bit of
the Config3 register when the ASE implementation is present).

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 0e1d7e7677c..b7c6d30723a 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -992,17 +992,21 @@ enum {
 #define GET_FEATURE_INSN(_flag, _hwcap) \
     do { if (cpu->env.insn_flags & (_flag)) { hwcaps |= _hwcap; } } while (0)
 
+#define GET_FEATURE_REG_SET(_reg, _mask, _hwcap) \
+    do { if (cpu->env._reg & (_mask)) { hwcaps |= _hwcap; } } while (0)
+
 static uint32_t get_elf_hwcap(void)
 {
     MIPSCPU *cpu = MIPS_CPU(thread_cpu);
     uint32_t hwcaps = 0;
 
     GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
-    GET_FEATURE_INSN(ASE_MSA, HWCAP_MIPS_MSA);
+    GET_FEATURE_REG_SET(CP0_Config3, 1 << CP0C3_MSAP, HWCAP_MIPS_MSA);
 
     return hwcaps;
 }
 
+#undef GET_FEATURE_REG_SET
 #undef GET_FEATURE_INSN
 
 #endif /* TARGET_MIPS */
-- 
2.26.2

Re: [PATCH v2 3/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_SET() macro

[Richard Henderson]

On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
> ISA features are usually denoted in read-only bits from
> CPU registers. Add the GET_FEATURE_REG_SET() macro which
> checks if a CPU register has bits set.
> 
> Use the macro to check for MSA (which sets the MSAP bit of
> the Config3 register when the ASE implementation is present).
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  linux-user/elfload.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~

[PATCH v2 4/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_EQU() macro

[Philippe Mathieu-Daudé]

ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_EQU() macro which
checks if a CPU register has bits set to a specific value.

Use the macro to check the 'Architecture Revision' level
of the Config0 register, which is '2' when the Release 6
ISA is implemented.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index b7c6d30723a..73c1972183b 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -995,17 +995,25 @@ enum {
 #define GET_FEATURE_REG_SET(_reg, _mask, _hwcap) \
     do { if (cpu->env._reg & (_mask)) { hwcaps |= _hwcap; } } while (0)
 
+#define GET_FEATURE_REG_EQU(_reg, _mask, _val, _hwcap) \
+    do { \
+        if ((cpu->env._reg & (_mask)) == _val) { \
+            hwcaps |= _hwcap; \
+        } \
+    } while (0)
+
 static uint32_t get_elf_hwcap(void)
 {
     MIPSCPU *cpu = MIPS_CPU(thread_cpu);
     uint32_t hwcaps = 0;
 
-    GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
+    GET_FEATURE_REG_EQU(CP0_Config0, 7 << CP0C0_AR, 2, HWCAP_MIPS_R6);
     GET_FEATURE_REG_SET(CP0_Config3, 1 << CP0C3_MSAP, HWCAP_MIPS_MSA);
 
     return hwcaps;
 }
 
+#undef GET_FEATURE_REG_EQU
 #undef GET_FEATURE_REG_SET
 #undef GET_FEATURE_INSN
 
-- 
2.26.2

Re: [PATCH v2 4/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_EQU() macro

[Richard Henderson]

On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
> +#define GET_FEATURE_REG_EQU(_reg, _mask, _val, _hwcap) \
> +    do { \
> +        if ((cpu->env._reg & (_mask)) == _val) { \
> +            hwcaps |= _hwcap; \
> +        } \
> +    } while (0)
> +
>  static uint32_t get_elf_hwcap(void)
>  {
>      MIPSCPU *cpu = MIPS_CPU(thread_cpu);
>      uint32_t hwcaps = 0;
>  
> -    GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
> +    GET_FEATURE_REG_EQU(CP0_Config0, 7 << CP0C0_AR, 2, HWCAP_MIPS_R6);

You'd need 2 << CP0C0_AR for the equality to match.
Would it be better to have the shift as a separate argument?


r~

Re: [PATCH v2 4/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_EQU() macro

[Philippe Mathieu-Daudé]

On 12/1/20 6:36 PM, Richard Henderson wrote:
> On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
>> +#define GET_FEATURE_REG_EQU(_reg, _mask, _val, _hwcap) \
>> +    do { \
>> +        if ((cpu->env._reg & (_mask)) == _val) { \
>> +            hwcaps |= _hwcap; \
>> +        } \
>> +    } while (0)
>> +
>>  static uint32_t get_elf_hwcap(void)
>>  {
>>      MIPSCPU *cpu = MIPS_CPU(thread_cpu);
>>      uint32_t hwcaps = 0;
>>  
>> -    GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
>> +    GET_FEATURE_REG_EQU(CP0_Config0, 7 << CP0C0_AR, 2, HWCAP_MIPS_R6);
> 
> You'd need 2 << CP0C0_AR for the equality to match.

Oops...

> Would it be better to have the shift as a separate argument?

Yes, thanks!

Phil.

[PATCH v2 5/6] linux-user/elfload: Update HWCAP bits from linux 5.7

[Philippe Mathieu-Daudé]

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 73c1972183b..167ffbfb06c 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -985,6 +985,19 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUMIPSState *e
 enum {
     HWCAP_MIPS_R6           = (1 << 0),
     HWCAP_MIPS_MSA          = (1 << 1),
+    HWCAP_MIPS_CRC32        = (1 << 2),
+    HWCAP_MIPS_MIPS16       = (1 << 3),
+    HWCAP_MIPS_MDMX         = (1 << 4),
+    HWCAP_MIPS_MIPS3D       = (1 << 5),
+    HWCAP_MIPS_SMARTMIPS    = (1 << 6),
+    HWCAP_MIPS_DSP          = (1 << 7),
+    HWCAP_MIPS_DSP2         = (1 << 8),
+    HWCAP_MIPS_DSP3         = (1 << 9),
+    HWCAP_MIPS_MIPS16E2     = (1 << 10),
+    HWCAP_LOONGSON_MMI      = (1 << 11),
+    HWCAP_LOONGSON_EXT      = (1 << 12),
+    HWCAP_LOONGSON_EXT2     = (1 << 13),
+    HWCAP_LOONGSON_CPUCFG   = (1 << 14),
 };
 
 #define ELF_HWCAP get_elf_hwcap()
-- 
2.26.2

[PATCH v2 6/6] linux-user: Add support for MIPS Loongson 2F/3E

[Philippe Mathieu-Daudé]

Userland ELF binaries using Longsoon SIMD instructions have the
HWCAP_LOONGSON_MMI bit set [1].
Binaries compiled for Longsoon 3E [2] have the HWCAP_LOONGSON_EXT
bit set for the LQ / SQ instructions.

[1] commit 8e2d5831e4b ("target/mips: Legalize Loongson insn flags")
[2] commit af868995e1b ("target/mips: Add Loongson-3 CPU definition")

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 linux-user/elfload.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 167ffbfb06c..3b4fc3126da 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1022,6 +1022,8 @@ static uint32_t get_elf_hwcap(void)
 
     GET_FEATURE_REG_EQU(CP0_Config0, 7 << CP0C0_AR, 2, HWCAP_MIPS_R6);
     GET_FEATURE_REG_SET(CP0_Config3, 1 << CP0C3_MSAP, HWCAP_MIPS_MSA);
+    GET_FEATURE_INSN(ASE_LMMI, HWCAP_LOONGSON_MMI);
+    GET_FEATURE_INSN(ASE_LEXT, HWCAP_LOONGSON_EXT);
 
     return hwcaps;
 }
-- 
2.26.2