diff mbox series

RISC-V: Add mvendorid, marchid, and mimpid to /proc/cpuinfo output

Message ID 20220620115549.1529597-1-apatel@ventanamicro.com (mailing list archive)
State New, archived
Headers show
Series RISC-V: Add mvendorid, marchid, and mimpid to /proc/cpuinfo output | expand

Commit Message

Anup Patel June 20, 2022, 11:55 a.m. UTC
Identifying the underlying RISC-V implementation can be important
for some of the user space applications. For example, the perf tool
uses arch specific CPU implementation id (i.e. CPUID) to select a
JSON file describing custom perf events on a CPU.

Currently, there is no way to identify RISC-V implementation so we
add mvendorid, marchid, and mimpid to /proc/cpuinfo output.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/kernel/cpu.c | 51 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

Comments

Heinrich Schuchardt June 20, 2022, 1:57 p.m. UTC | #1
On 6/20/22 13:55, Anup Patel wrote:
> Identifying the underlying RISC-V implementation can be important
> for some of the user space applications. For example, the perf tool
> uses arch specific CPU implementation id (i.e. CPUID) to select a
> JSON file describing custom perf events on a CPU.
> 
> Currently, there is no way to identify RISC-V implementation so we
> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>

Looks good to me. I only tested on QEMU where all values default to 0.

Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

> ---
>   arch/riscv/kernel/cpu.c | 51 +++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 51 insertions(+)
> 
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index fba9e9f46a8c..c037b8691bbb 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -3,10 +3,13 @@
>    * Copyright (C) 2012 Regents of the University of California
>    */
>   
> +#include <linux/cpu.h>
>   #include <linux/init.h>
>   #include <linux/seq_file.h>
>   #include <linux/of.h>
> +#include <asm/csr.h>
>   #include <asm/hwcap.h>
> +#include <asm/sbi.h>
>   #include <asm/smp.h>
>   #include <asm/pgtable.h>
>   
> @@ -64,6 +67,50 @@ int riscv_of_parent_hartid(struct device_node *node)
>   }
>   
>   #ifdef CONFIG_PROC_FS
> +
> +struct riscv_cpuinfo {
> +	unsigned long mvendorid;
> +	unsigned long marchid;
> +	unsigned long mimpid;
> +};
> +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> +
> +static int riscv_cpuinfo_starting(unsigned int cpu)
> +{
> +	struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if defined(CONFIG_RISCV_SBI)
> +	ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> +	ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> +	ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> +#elif defined(CONFIG_RISCV_M_MODE)
> +	ci->mvendorid = csr_read(CSR_MVENDORID);
> +	ci->marchid = csr_read(CSR_MARCHID);
> +	ci->mimpid = csr_read(CSR_MIMPID);
> +#else
> +	ci->mvendorid = 0;
> +	ci->marchid = 0;
> +	ci->mimpid = 0;
> +#endif
> +
> +	return 0;
> +}
> +
> +static int __init riscv_cpuinfo_init(void)
> +{
> +	int ret;
> +
> +	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting",
> +				riscv_cpuinfo_starting, NULL);
> +	if (ret < 0) {
> +		pr_err("cpuinfo: failed to register hotplug callbacks.\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +device_initcall(riscv_cpuinfo_init);
> +
>   #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
>   	{							\
>   		.uprop = #UPROP,				\
> @@ -178,6 +225,7 @@ static int c_show(struct seq_file *m, void *v)
>   {
>   	unsigned long cpu_id = (unsigned long)v - 1;
>   	struct device_node *node = of_get_cpu_node(cpu_id, NULL);
> +	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
>   	const char *compat, *isa;
>   
>   	seq_printf(m, "processor\t: %lu\n", cpu_id);
> @@ -188,6 +236,9 @@ static int c_show(struct seq_file *m, void *v)
>   	if (!of_property_read_string(node, "compatible", &compat)
>   	    && strcmp(compat, "riscv"))
>   		seq_printf(m, "uarch\t\t: %s\n", compat);
> +	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
> +	seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
> +	seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
>   	seq_puts(m, "\n");
>   	of_node_put(node);
>
Conor Dooley June 20, 2022, 3:42 p.m. UTC | #2
Hey Anup,
Tested it & got back the (sadly boring) 0s that are set in
my hardware.

Two comments below.

Thanks,
Conor.

On 20/06/2022 12:55, Anup Patel wrote:
> Identifying the underlying RISC-V implementation can be important
> for some of the user space applications. For example, the perf tool
> uses arch specific CPU implementation id (i.e. CPUID) to select a
> JSON file describing custom perf events on a CPU.
> 
> Currently, there is no way to identify RISC-V implementation so we
> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
>  arch/riscv/kernel/cpu.c | 51 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
> 
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index fba9e9f46a8c..c037b8691bbb 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -3,10 +3,13 @@
>   * Copyright (C) 2012 Regents of the University of California
>   */
>  
> +#include <linux/cpu.h>
>  #include <linux/init.h>
>  #include <linux/seq_file.h>
>  #include <linux/of.h>
> +#include <asm/csr.h>
>  #include <asm/hwcap.h>
> +#include <asm/sbi.h>
>  #include <asm/smp.h>
>  #include <asm/pgtable.h>
>  
> @@ -64,6 +67,50 @@ int riscv_of_parent_hartid(struct device_node *node)
>  }
>  
>  #ifdef CONFIG_PROC_FS
> +
> +struct riscv_cpuinfo {
> +	unsigned long mvendorid;
> +	unsigned long marchid;
> +	unsigned long mimpid;
> +};
> +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> +
> +static int riscv_cpuinfo_starting(unsigned int cpu)
> +{
> +	struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if defined(CONFIG_RISCV_SBI)

This should be #if IS_ENABLED(CONFIG_RISCV_SBI) to match the
other users

> +	ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> +	ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> +	ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> +#elif defined(CONFIG_RISCV_M_MODE)

Ditto

> +	ci->mvendorid = csr_read(CSR_MVENDORID);
> +	ci->marchid = csr_read(CSR_MARCHID);
> +	ci->mimpid = csr_read(CSR_MIMPID);
> +#else
> +	ci->mvendorid = 0;
> +	ci->marchid = 0;
> +	ci->mimpid = 0;
> +#endif
> +
> +	return 0;
> +}
> +
> +static int __init riscv_cpuinfo_init(void)
> +{
> +	int ret;
> +
> +	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting",
> +				riscv_cpuinfo_starting, NULL);
> +	if (ret < 0) {
> +		pr_err("cpuinfo: failed to register hotplug callbacks.\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +device_initcall(riscv_cpuinfo_init);
> +
>  #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
>  	{							\
>  		.uprop = #UPROP,				\
> @@ -178,6 +225,7 @@ static int c_show(struct seq_file *m, void *v)
>  {
>  	unsigned long cpu_id = (unsigned long)v - 1;
>  	struct device_node *node = of_get_cpu_node(cpu_id, NULL);
> +	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
>  	const char *compat, *isa;
>  
>  	seq_printf(m, "processor\t: %lu\n", cpu_id);
> @@ -188,6 +236,9 @@ static int c_show(struct seq_file *m, void *v)
>  	if (!of_property_read_string(node, "compatible", &compat)
>  	    && strcmp(compat, "riscv"))
>  		seq_printf(m, "uarch\t\t: %s\n", compat);
> +	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
> +	seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
> +	seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
>  	seq_puts(m, "\n");
>  	of_node_put(node);
>
Nikita Shubin June 21, 2022, 7:40 a.m. UTC | #3
Hello Anup!

On Mon, 20 Jun 2022 17:25:49 +0530
Anup Patel <apatel@ventanamicro.com> wrote:

> Identifying the underlying RISC-V implementation can be important
> for some of the user space applications. For example, the perf tool
> uses arch specific CPU implementation id (i.e. CPUID) to select a
> JSON file describing custom perf events on a CPU.
> 
> Currently, there is no way to identify RISC-V implementation so we
> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.

Tested on Sifive Unmatched:

localhost / # cat /proc/cpuinfo 
processor       : 0
hart            : 4
isa             : rv64imafdc
mmu             : sv39
uarch           : sifive,bullet0
mvendorid       : 0x489
marchid         : 0x8000000000000007
mimpid          : 0x20181004

processor       : 1
hart            : 1
isa             : rv64imafdc
mmu             : sv39
uarch           : sifive,bullet0
mvendorid       : 0x489
marchid         : 0x8000000000000007
mimpid          : 0x20181004

processor       : 2
hart            : 2
isa             : rv64imafdc
mmu             : sv39
uarch           : sifive,bullet0
mvendorid       : 0x489
marchid         : 0x8000000000000007
mimpid          : 0x20181004

processor       : 3
hart            : 3
isa             : rv64imafdc
mmu             : sv39
uarch           : sifive,bullet0
mvendorid       : 0x489
marchid         : 0x8000000000000007
mimpid          : 0x20181004

mvendorid, marchid values match the register description in u74 manual.

mimpid seems to be ok, through i can't find exact in U74/Unmatched docs.

Tested-by: Nikita Shubin <n.shubin@yadro.com>

> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
>  arch/riscv/kernel/cpu.c | 51
> +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51
> insertions(+)
> 
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index fba9e9f46a8c..c037b8691bbb 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -3,10 +3,13 @@
>   * Copyright (C) 2012 Regents of the University of California
>   */
>  
> +#include <linux/cpu.h>
>  #include <linux/init.h>
>  #include <linux/seq_file.h>
>  #include <linux/of.h>
> +#include <asm/csr.h>
>  #include <asm/hwcap.h>
> +#include <asm/sbi.h>
>  #include <asm/smp.h>
>  #include <asm/pgtable.h>
>  
> @@ -64,6 +67,50 @@ int riscv_of_parent_hartid(struct device_node
> *node) }
>  
>  #ifdef CONFIG_PROC_FS
> +
> +struct riscv_cpuinfo {
> +	unsigned long mvendorid;
> +	unsigned long marchid;
> +	unsigned long mimpid;
> +};
> +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> +
> +static int riscv_cpuinfo_starting(unsigned int cpu)
> +{
> +	struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if defined(CONFIG_RISCV_SBI)
> +	ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> +	ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> +	ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> +#elif defined(CONFIG_RISCV_M_MODE)
> +	ci->mvendorid = csr_read(CSR_MVENDORID);
> +	ci->marchid = csr_read(CSR_MARCHID);
> +	ci->mimpid = csr_read(CSR_MIMPID);
> +#else
> +	ci->mvendorid = 0;
> +	ci->marchid = 0;
> +	ci->mimpid = 0;
> +#endif
> +
> +	return 0;
> +}
> +
> +static int __init riscv_cpuinfo_init(void)
> +{
> +	int ret;
> +
> +	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
> "riscv/cpuinfo:starting",
> +				riscv_cpuinfo_starting, NULL);
> +	if (ret < 0) {
> +		pr_err("cpuinfo: failed to register hotplug
> callbacks.\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +device_initcall(riscv_cpuinfo_init);
> +
>  #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
>  	{							\
>  		.uprop = #UPROP,				\
> @@ -178,6 +225,7 @@ static int c_show(struct seq_file *m, void *v)
>  {
>  	unsigned long cpu_id = (unsigned long)v - 1;
>  	struct device_node *node = of_get_cpu_node(cpu_id, NULL);
> +	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo,
> cpu_id); const char *compat, *isa;
>  
>  	seq_printf(m, "processor\t: %lu\n", cpu_id);
> @@ -188,6 +236,9 @@ static int c_show(struct seq_file *m, void *v)
>  	if (!of_property_read_string(node, "compatible", &compat)
>  	    && strcmp(compat, "riscv"))
>  		seq_printf(m, "uarch\t\t: %s\n", compat);
> +	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
> +	seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
> +	seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
>  	seq_puts(m, "\n");
>  	of_node_put(node);
>
David Abdurachmanov June 21, 2022, 8:28 a.m. UTC | #4
On Tue, Jun 21, 2022 at 10:53 AM Nikita Shubin
<nikita.shubin@maquefel.me> wrote:
>
> Hello Anup!
>
> On Mon, 20 Jun 2022 17:25:49 +0530
> Anup Patel <apatel@ventanamicro.com> wrote:
>
> > Identifying the underlying RISC-V implementation can be important
> > for some of the user space applications. For example, the perf tool
> > uses arch specific CPU implementation id (i.e. CPUID) to select a
> > JSON file describing custom perf events on a CPU.
> >
> > Currently, there is no way to identify RISC-V implementation so we
> > add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
>
> Tested on Sifive Unmatched:
>
> localhost / # cat /proc/cpuinfo
> processor       : 0
> hart            : 4
> isa             : rv64imafdc
> mmu             : sv39
> uarch           : sifive,bullet0
> mvendorid       : 0x489
> marchid         : 0x8000000000000007
> mimpid          : 0x20181004
>
> processor       : 1
> hart            : 1
> isa             : rv64imafdc
> mmu             : sv39
> uarch           : sifive,bullet0
> mvendorid       : 0x489
> marchid         : 0x8000000000000007
> mimpid          : 0x20181004
>
> processor       : 2
> hart            : 2
> isa             : rv64imafdc
> mmu             : sv39
> uarch           : sifive,bullet0
> mvendorid       : 0x489
> marchid         : 0x8000000000000007
> mimpid          : 0x20181004
>
> processor       : 3
> hart            : 3
> isa             : rv64imafdc
> mmu             : sv39
> uarch           : sifive,bullet0
> mvendorid       : 0x489
> marchid         : 0x8000000000000007
> mimpid          : 0x20181004
>
> mvendorid, marchid values match the register description in u74 manual.
>
> mimpid seems to be ok, through i can't find exact in U74/Unmatched docs.

SiFive main website -> Products -> Documentation -> U74-MC Core
Complex Manual -> Page 274: B.2 Machine Implementation ID Register
(mimpid).

This mimpid value is not in the table thus it's most likely not part
of a particular U74 generator release. Looking at this value we could
assume that U74 cores within FU740 predates the general availability.

Cheers,
david

>
> Tested-by: Nikita Shubin <n.shubin@yadro.com>
>
> >
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > ---
> >  arch/riscv/kernel/cpu.c | 51
> > +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51
> > insertions(+)
> >
> > diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> > index fba9e9f46a8c..c037b8691bbb 100644
> > --- a/arch/riscv/kernel/cpu.c
> > +++ b/arch/riscv/kernel/cpu.c
> > @@ -3,10 +3,13 @@
> >   * Copyright (C) 2012 Regents of the University of California
> >   */
> >
> > +#include <linux/cpu.h>
> >  #include <linux/init.h>
> >  #include <linux/seq_file.h>
> >  #include <linux/of.h>
> > +#include <asm/csr.h>
> >  #include <asm/hwcap.h>
> > +#include <asm/sbi.h>
> >  #include <asm/smp.h>
> >  #include <asm/pgtable.h>
> >
> > @@ -64,6 +67,50 @@ int riscv_of_parent_hartid(struct device_node
> > *node) }
> >
> >  #ifdef CONFIG_PROC_FS
> > +
> > +struct riscv_cpuinfo {
> > +     unsigned long mvendorid;
> > +     unsigned long marchid;
> > +     unsigned long mimpid;
> > +};
> > +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> > +
> > +static int riscv_cpuinfo_starting(unsigned int cpu)
> > +{
> > +     struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> > +
> > +#if defined(CONFIG_RISCV_SBI)
> > +     ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> > +     ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> > +     ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> > +#elif defined(CONFIG_RISCV_M_MODE)
> > +     ci->mvendorid = csr_read(CSR_MVENDORID);
> > +     ci->marchid = csr_read(CSR_MARCHID);
> > +     ci->mimpid = csr_read(CSR_MIMPID);
> > +#else
> > +     ci->mvendorid = 0;
> > +     ci->marchid = 0;
> > +     ci->mimpid = 0;
> > +#endif
> > +
> > +     return 0;
> > +}
> > +
> > +static int __init riscv_cpuinfo_init(void)
> > +{
> > +     int ret;
> > +
> > +     ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
> > "riscv/cpuinfo:starting",
> > +                             riscv_cpuinfo_starting, NULL);
> > +     if (ret < 0) {
> > +             pr_err("cpuinfo: failed to register hotplug
> > callbacks.\n");
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +device_initcall(riscv_cpuinfo_init);
> > +
> >  #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
> >       {                                                       \
> >               .uprop = #UPROP,                                \
> > @@ -178,6 +225,7 @@ static int c_show(struct seq_file *m, void *v)
> >  {
> >       unsigned long cpu_id = (unsigned long)v - 1;
> >       struct device_node *node = of_get_cpu_node(cpu_id, NULL);
> > +     struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo,
> > cpu_id); const char *compat, *isa;
> >
> >       seq_printf(m, "processor\t: %lu\n", cpu_id);
> > @@ -188,6 +236,9 @@ static int c_show(struct seq_file *m, void *v)
> >       if (!of_property_read_string(node, "compatible", &compat)
> >           && strcmp(compat, "riscv"))
> >               seq_printf(m, "uarch\t\t: %s\n", compat);
> > +     seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
> > +     seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
> > +     seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
> >       seq_puts(m, "\n");
> >       of_node_put(node);
> >
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
Anup Patel July 26, 2022, 11:57 a.m. UTC | #5
Hi Palmer,

On Mon, Jun 20, 2022 at 5:26 PM Anup Patel <apatel@ventanamicro.com> wrote:
>
> Identifying the underlying RISC-V implementation can be important
> for some of the user space applications. For example, the perf tool
> uses arch specific CPU implementation id (i.e. CPUID) to select a
> JSON file describing custom perf events on a CPU.
>
> Currently, there is no way to identify RISC-V implementation so we
> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>

Can this patch be considered for 5.20 ?

Regards,
Anup

> ---
>  arch/riscv/kernel/cpu.c | 51 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index fba9e9f46a8c..c037b8691bbb 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -3,10 +3,13 @@
>   * Copyright (C) 2012 Regents of the University of California
>   */
>
> +#include <linux/cpu.h>
>  #include <linux/init.h>
>  #include <linux/seq_file.h>
>  #include <linux/of.h>
> +#include <asm/csr.h>
>  #include <asm/hwcap.h>
> +#include <asm/sbi.h>
>  #include <asm/smp.h>
>  #include <asm/pgtable.h>
>
> @@ -64,6 +67,50 @@ int riscv_of_parent_hartid(struct device_node *node)
>  }
>
>  #ifdef CONFIG_PROC_FS
> +
> +struct riscv_cpuinfo {
> +       unsigned long mvendorid;
> +       unsigned long marchid;
> +       unsigned long mimpid;
> +};
> +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> +
> +static int riscv_cpuinfo_starting(unsigned int cpu)
> +{
> +       struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if defined(CONFIG_RISCV_SBI)
> +       ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> +       ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> +       ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> +#elif defined(CONFIG_RISCV_M_MODE)
> +       ci->mvendorid = csr_read(CSR_MVENDORID);
> +       ci->marchid = csr_read(CSR_MARCHID);
> +       ci->mimpid = csr_read(CSR_MIMPID);
> +#else
> +       ci->mvendorid = 0;
> +       ci->marchid = 0;
> +       ci->mimpid = 0;
> +#endif
> +
> +       return 0;
> +}
> +
> +static int __init riscv_cpuinfo_init(void)
> +{
> +       int ret;
> +
> +       ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting",
> +                               riscv_cpuinfo_starting, NULL);
> +       if (ret < 0) {
> +               pr_err("cpuinfo: failed to register hotplug callbacks.\n");
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +device_initcall(riscv_cpuinfo_init);
> +
>  #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
>         {                                                       \
>                 .uprop = #UPROP,                                \
> @@ -178,6 +225,7 @@ static int c_show(struct seq_file *m, void *v)
>  {
>         unsigned long cpu_id = (unsigned long)v - 1;
>         struct device_node *node = of_get_cpu_node(cpu_id, NULL);
> +       struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
>         const char *compat, *isa;
>
>         seq_printf(m, "processor\t: %lu\n", cpu_id);
> @@ -188,6 +236,9 @@ static int c_show(struct seq_file *m, void *v)
>         if (!of_property_read_string(node, "compatible", &compat)
>             && strcmp(compat, "riscv"))
>                 seq_printf(m, "uarch\t\t: %s\n", compat);
> +       seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
> +       seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
> +       seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
>         seq_puts(m, "\n");
>         of_node_put(node);
>
> --
> 2.34.1
>
Conor Dooley July 26, 2022, 1:40 p.m. UTC | #6
Hey Anup,

On 26/07/2022 12:57, Anup Patel wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Hi Palmer,
> 
> On Mon, Jun 20, 2022 at 5:26 PM Anup Patel <apatel@ventanamicro.com> wrote:
>>
>> Identifying the underlying RISC-V implementation can be important
>> for some of the user space applications. For example, the perf tool
>> uses arch specific CPU implementation id (i.e. CPUID) to select a
>> JSON file describing custom perf events on a CPU.
>>
>> Currently, there is no way to identify RISC-V implementation so we
>> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
>>
>> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> 
> Can this patch be considered for 5.20 ?

iirc I mentioned the consistency of using defined() for
CONFIG_RISCV_SBI versus IS_ENABLED() elsewhere in arch/riscv/
but I don't recall a response.

Thanks,
Conor.
Anup Patel July 26, 2022, 1:43 p.m. UTC | #7
On Tue, Jul 26, 2022 at 7:10 PM <Conor.Dooley@microchip.com> wrote:
>
> Hey Anup,
>
> On 26/07/2022 12:57, Anup Patel wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >
> > Hi Palmer,
> >
> > On Mon, Jun 20, 2022 at 5:26 PM Anup Patel <apatel@ventanamicro.com> wrote:
> >>
> >> Identifying the underlying RISC-V implementation can be important
> >> for some of the user space applications. For example, the perf tool
> >> uses arch specific CPU implementation id (i.e. CPUID) to select a
> >> JSON file describing custom perf events on a CPU.
> >>
> >> Currently, there is no way to identify RISC-V implementation so we
> >> add mvendorid, marchid, and mimpid to /proc/cpuinfo output.
> >>
> >> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> >
> > Can this patch be considered for 5.20 ?
>
> iirc I mentioned the consistency of using defined() for
> CONFIG_RISCV_SBI versus IS_ENABLED() elsewhere in arch/riscv/
> but I don't recall a response.

Sorry, I missed your comment. I will address and send v2 soon.

Regards,
Anup

>
> Thanks,
> Conor.
diff mbox series

Patch

diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index fba9e9f46a8c..c037b8691bbb 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -3,10 +3,13 @@ 
  * Copyright (C) 2012 Regents of the University of California
  */
 
+#include <linux/cpu.h>
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/of.h>
+#include <asm/csr.h>
 #include <asm/hwcap.h>
+#include <asm/sbi.h>
 #include <asm/smp.h>
 #include <asm/pgtable.h>
 
@@ -64,6 +67,50 @@  int riscv_of_parent_hartid(struct device_node *node)
 }
 
 #ifdef CONFIG_PROC_FS
+
+struct riscv_cpuinfo {
+	unsigned long mvendorid;
+	unsigned long marchid;
+	unsigned long mimpid;
+};
+static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
+
+static int riscv_cpuinfo_starting(unsigned int cpu)
+{
+	struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
+
+#if defined(CONFIG_RISCV_SBI)
+	ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
+	ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
+	ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
+#elif defined(CONFIG_RISCV_M_MODE)
+	ci->mvendorid = csr_read(CSR_MVENDORID);
+	ci->marchid = csr_read(CSR_MARCHID);
+	ci->mimpid = csr_read(CSR_MIMPID);
+#else
+	ci->mvendorid = 0;
+	ci->marchid = 0;
+	ci->mimpid = 0;
+#endif
+
+	return 0;
+}
+
+static int __init riscv_cpuinfo_init(void)
+{
+	int ret;
+
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting",
+				riscv_cpuinfo_starting, NULL);
+	if (ret < 0) {
+		pr_err("cpuinfo: failed to register hotplug callbacks.\n");
+		return ret;
+	}
+
+	return 0;
+}
+device_initcall(riscv_cpuinfo_init);
+
 #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
 	{							\
 		.uprop = #UPROP,				\
@@ -178,6 +225,7 @@  static int c_show(struct seq_file *m, void *v)
 {
 	unsigned long cpu_id = (unsigned long)v - 1;
 	struct device_node *node = of_get_cpu_node(cpu_id, NULL);
+	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
 	const char *compat, *isa;
 
 	seq_printf(m, "processor\t: %lu\n", cpu_id);
@@ -188,6 +236,9 @@  static int c_show(struct seq_file *m, void *v)
 	if (!of_property_read_string(node, "compatible", &compat)
 	    && strcmp(compat, "riscv"))
 		seq_printf(m, "uarch\t\t: %s\n", compat);
+	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
+	seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
+	seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
 	seq_puts(m, "\n");
 	of_node_put(node);