From: Heiko Stuebner <[email protected]>
When filling hwcap the kernel already expects the isa string to start with
rv32 if CONFIG_32BIT and rv64 if CONFIG_64BIT.
So when recreating the runtime isa-string we can also just go the other way
to get the correct starting point for it.
Signed-off-by: Heiko Stuebner <[email protected]>
---
arch/riscv/kernel/cpu.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index ebc478f0a16c..06c2f587a176 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -244,7 +244,7 @@ static void strcat_isa_ext(char *isa_str)
*/
static const char base_riscv_exts[13] = "imafdqcbkjpvh";
-static char *riscv_create_isa_string(const char *isa)
+static char *riscv_create_isa_string(void)
{
int maxlen = 4;
char *isa_str;
@@ -261,7 +261,11 @@ static char *riscv_create_isa_string(const char *isa)
return ERR_PTR(-ENOMEM);
/* Print the rv[64/32] part */
- strncat(isa_str, isa, 4);
+#if IS_ENABLED(CONFIG_32BIT)
+ strncat(isa_str, "rv32", 4);
+#elif IS_ENABLED(CONFIG_64BIT)
+ strncat(isa_str, "rv64", 4);
+#endif
for (i = 0; i < sizeof(base_riscv_exts); i++) {
if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a'))
@@ -280,7 +284,7 @@ static void print_isa(struct seq_file *f, const char *isa)
seq_puts(f, "isa\t\t: ");
- isa_str = riscv_create_isa_string(isa);
+ isa_str = riscv_create_isa_string();
if (!IS_ERR(isa_str)) {
seq_write(f, isa_str, strlen(isa_str));
kfree(isa_str);
--
2.39.0
On Mon, Apr 24, 2023 at 09:49:09PM +0200, Heiko Stuebner wrote:
> From: Heiko Stuebner <[email protected]>
>
> When filling hwcap the kernel already expects the isa string to start with
> rv32 if CONFIG_32BIT and rv64 if CONFIG_64BIT.
>
> So when recreating the runtime isa-string we can also just go the other way
> to get the correct starting point for it.
>
> Signed-off-by: Heiko Stuebner <[email protected]>
> ---
> arch/riscv/kernel/cpu.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index ebc478f0a16c..06c2f587a176 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -244,7 +244,7 @@ static void strcat_isa_ext(char *isa_str)
> */
> static const char base_riscv_exts[13] = "imafdqcbkjpvh";
>
> -static char *riscv_create_isa_string(const char *isa)
> +static char *riscv_create_isa_string(void)
> {
> int maxlen = 4;
> char *isa_str;
> @@ -261,7 +261,11 @@ static char *riscv_create_isa_string(const char *isa)
> return ERR_PTR(-ENOMEM);
>
> /* Print the rv[64/32] part */
> - strncat(isa_str, isa, 4);
> +#if IS_ENABLED(CONFIG_32BIT)
> + strncat(isa_str, "rv32", 4);
> +#elif IS_ENABLED(CONFIG_64BIT)
> + strncat(isa_str, "rv64", 4);
> +#endif
I see we do the validation in riscv_fill_hwcap() and we also do this
#ifdeffery there, but I can't see any reason not to do
if (IS_ENABLED(CONFIG_32BIT))
...
else
...
instead.
>
> for (i = 0; i < sizeof(base_riscv_exts); i++) {
> if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a'))
> @@ -280,7 +284,7 @@ static void print_isa(struct seq_file *f, const char *isa)
>
> seq_puts(f, "isa\t\t: ");
>
> - isa_str = riscv_create_isa_string(isa);
> + isa_str = riscv_create_isa_string();
Why are we still passing 'isa' to print_isa()? It's now unused and
print_isa()'s single caller only fetches it from the DT for this
one purpose, so that of_property_read_string() call could now also
be dropped.
> if (!IS_ERR(isa_str)) {
> seq_write(f, isa_str, strlen(isa_str));
> kfree(isa_str);
> --
> 2.39.0
>
Thanks,
drew
On Mon, 24 Apr 2023 12:49:09 PDT (-0700), [email protected] wrote:
> From: Heiko Stuebner <[email protected]>
>
> When filling hwcap the kernel already expects the isa string to start with
> rv32 if CONFIG_32BIT and rv64 if CONFIG_64BIT.
>
> So when recreating the runtime isa-string we can also just go the other way
> to get the correct starting point for it.
>
> Signed-off-by: Heiko Stuebner <[email protected]>
> ---
> arch/riscv/kernel/cpu.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index ebc478f0a16c..06c2f587a176 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -244,7 +244,7 @@ static void strcat_isa_ext(char *isa_str)
> */
> static const char base_riscv_exts[13] = "imafdqcbkjpvh";
>
> -static char *riscv_create_isa_string(const char *isa)
> +static char *riscv_create_isa_string(void)
> {
> int maxlen = 4;
> char *isa_str;
> @@ -261,7 +261,11 @@ static char *riscv_create_isa_string(const char *isa)
> return ERR_PTR(-ENOMEM);
>
> /* Print the rv[64/32] part */
> - strncat(isa_str, isa, 4);
> +#if IS_ENABLED(CONFIG_32BIT)
> + strncat(isa_str, "rv32", 4);
> +#elif IS_ENABLED(CONFIG_64BIT)
> + strncat(isa_str, "rv64", 4);
> +#endif
>
> for (i = 0; i < sizeof(base_riscv_exts); i++) {
> if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a'))
> @@ -280,7 +284,7 @@ static void print_isa(struct seq_file *f, const char *isa)
>
> seq_puts(f, "isa\t\t: ");
>
> - isa_str = riscv_create_isa_string(isa);
> + isa_str = riscv_create_isa_string();
> if (!IS_ERR(isa_str)) {
> seq_write(f, isa_str, strlen(isa_str));
> kfree(isa_str);
Conor pointed out this one, I just looked at the cover letter and got
distracted by uABI stuff. It's not directly fixing anything so I'm
going to leave it out of this merge window, particularly given that it's
tied up with the rest.
Reviewed-by: Palmer Dabbelt <[email protected]>