From: Atish Patra <atishp@rivosinc.com>
RISC-V SBI specification supports advanced debug console
support via SBI DBCN extension.
Extend the HVC SBI driver to support it.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
drivers/tty/hvc/Kconfig | 2 +-
drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
2 files changed, 76 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
index 4f9264d005c0..6e05c5c7bca1 100644
--- a/drivers/tty/hvc/Kconfig
+++ b/drivers/tty/hvc/Kconfig
@@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
config HVC_RISCV_SBI
bool "RISC-V SBI console support"
- depends on RISCV_SBI_V01
+ depends on RISCV_SBI
select HVC_DRIVER
help
This enables support for console output via RISC-V SBI calls, which
diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
index 31f53fa77e4a..56da1a4b5aca 100644
--- a/drivers/tty/hvc/hvc_riscv_sbi.c
+++ b/drivers/tty/hvc/hvc_riscv_sbi.c
@@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
return i;
}
-static const struct hv_ops hvc_sbi_ops = {
+static const struct hv_ops hvc_sbi_v01_ops = {
.get_chars = hvc_sbi_tty_get,
.put_chars = hvc_sbi_tty_put,
};
-static int __init hvc_sbi_init(void)
+static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
{
- return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
+ phys_addr_t pa;
+ struct sbiret ret;
+
+ if (is_vmalloc_addr(buf)) {
+ pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
+ if (PAGE_SIZE < (offset_in_page(buf) + count))
+ count = PAGE_SIZE - offset_in_page(buf);
+ } else {
+ pa = __pa(buf);
+ }
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
+ count, lower_32_bits(pa), upper_32_bits(pa),
+ 0, 0, 0);
+ else
+ ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
+ count, pa, 0, 0, 0, 0);
+ if (ret.error)
+ return 0;
+
+ return count;
}
-device_initcall(hvc_sbi_init);
-static int __init hvc_sbi_console_init(void)
+static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)
{
- hvc_instantiate(0, 0, &hvc_sbi_ops);
+ phys_addr_t pa;
+ struct sbiret ret;
+
+ if (is_vmalloc_addr(buf)) {
+ pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
+ if (PAGE_SIZE < (offset_in_page(buf) + count))
+ count = PAGE_SIZE - offset_in_page(buf);
+ } else {
+ pa = __pa(buf);
+ }
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
+ count, lower_32_bits(pa), upper_32_bits(pa),
+ 0, 0, 0);
+ else
+ ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
+ count, pa, 0, 0, 0, 0);
+ if (ret.error)
+ return 0;
+
+ return ret.value;
+}
+
+static const struct hv_ops hvc_sbi_dbcn_ops = {
+ .put_chars = hvc_sbi_dbcn_tty_put,
+ .get_chars = hvc_sbi_dbcn_tty_get,
+};
+
+static int __init hvc_sbi_init(void)
+{
+ int err;
+
+ if ((sbi_spec_version >= sbi_mk_version(2, 0)) &&
+ (sbi_probe_extension(SBI_EXT_DBCN) > 0)) {
+ err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_dbcn_ops, 16));
+ if (err)
+ return err;
+ hvc_instantiate(0, 0, &hvc_sbi_dbcn_ops);
+ } else {
+ if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) {
+ err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_v01_ops, 16));
+ if (err)
+ return err;
+ hvc_instantiate(0, 0, &hvc_sbi_v01_ops);
+ } else {
+ return -ENODEV;
+ }
+ }
return 0;
}
-console_initcall(hvc_sbi_console_init);
+device_initcall(hvc_sbi_init);
--
2.34.1On Fri, Oct 20, 2023 at 12:51:39PM +0530, Anup Patel wrote:
> From: Atish Patra <atishp@rivosinc.com>
>
> RISC-V SBI specification supports advanced debug console
> support via SBI DBCN extension.
>
> Extend the HVC SBI driver to support it.
>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
> drivers/tty/hvc/Kconfig | 2 +-
> drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> 2 files changed, 76 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> index 4f9264d005c0..6e05c5c7bca1 100644
> --- a/drivers/tty/hvc/Kconfig
> +++ b/drivers/tty/hvc/Kconfig
> @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
>
> config HVC_RISCV_SBI
> bool "RISC-V SBI console support"
> - depends on RISCV_SBI_V01
> + depends on RISCV_SBI
> select HVC_DRIVER
> help
> This enables support for console output via RISC-V SBI calls, which
> diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> index 31f53fa77e4a..56da1a4b5aca 100644
> --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> return i;
> }
>
> -static const struct hv_ops hvc_sbi_ops = {
> +static const struct hv_ops hvc_sbi_v01_ops = {
> .get_chars = hvc_sbi_tty_get,
> .put_chars = hvc_sbi_tty_put,
> };
>
> -static int __init hvc_sbi_init(void)
> +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> {
> - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf)) {
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + if (PAGE_SIZE < (offset_in_page(buf) + count))
> + count = PAGE_SIZE - offset_in_page(buf);
> + } else {
> + pa = __pa(buf);
> + }
> +
> + if (IS_ENABLED(CONFIG_32BIT))
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> + count, lower_32_bits(pa), upper_32_bits(pa),
> + 0, 0, 0);
> + else
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> + count, pa, 0, 0, 0, 0);
Again, you need a helper function here to keep you from having to keep
this all in sync.
> + if (ret.error)
> + return 0;
> +
> + return count;
> }
> -device_initcall(hvc_sbi_init);
>
> -static int __init hvc_sbi_console_init(void)
> +static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)
> {
> - hvc_instantiate(0, 0, &hvc_sbi_ops);
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf)) {
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + if (PAGE_SIZE < (offset_in_page(buf) + count))
> + count = PAGE_SIZE - offset_in_page(buf);
> + } else {
> + pa = __pa(buf);
> + }
> +
> + if (IS_ENABLED(CONFIG_32BIT))
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> + count, lower_32_bits(pa), upper_32_bits(pa),
> + 0, 0, 0);
> + else
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> + count, pa, 0, 0, 0, 0);
And here too.
thanks,
greg k-h
On Sat, Oct 21, 2023 at 10:16 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Fri, Oct 20, 2023 at 12:51:39PM +0530, Anup Patel wrote:
> > From: Atish Patra <atishp@rivosinc.com>
> >
> > RISC-V SBI specification supports advanced debug console
> > support via SBI DBCN extension.
> >
> > Extend the HVC SBI driver to support it.
> >
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > ---
> > drivers/tty/hvc/Kconfig | 2 +-
> > drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> > 2 files changed, 76 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> > index 4f9264d005c0..6e05c5c7bca1 100644
> > --- a/drivers/tty/hvc/Kconfig
> > +++ b/drivers/tty/hvc/Kconfig
> > @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
> >
> > config HVC_RISCV_SBI
> > bool "RISC-V SBI console support"
> > - depends on RISCV_SBI_V01
> > + depends on RISCV_SBI
> > select HVC_DRIVER
> > help
> > This enables support for console output via RISC-V SBI calls, which
> > diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> > index 31f53fa77e4a..56da1a4b5aca 100644
> > --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> > +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> > @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> > return i;
> > }
> >
> > -static const struct hv_ops hvc_sbi_ops = {
> > +static const struct hv_ops hvc_sbi_v01_ops = {
> > .get_chars = hvc_sbi_tty_get,
> > .put_chars = hvc_sbi_tty_put,
> > };
> >
> > -static int __init hvc_sbi_init(void)
> > +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> > {
> > - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> > + phys_addr_t pa;
> > + struct sbiret ret;
> > +
> > + if (is_vmalloc_addr(buf)) {
> > + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> > + if (PAGE_SIZE < (offset_in_page(buf) + count))
> > + count = PAGE_SIZE - offset_in_page(buf);
> > + } else {
> > + pa = __pa(buf);
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_32BIT))
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> > + count, lower_32_bits(pa), upper_32_bits(pa),
> > + 0, 0, 0);
> > + else
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> > + count, pa, 0, 0, 0, 0);
>
> Again, you need a helper function here to keep you from having to keep
> this all in sync.
Sure, I will update.
>
> > + if (ret.error)
> > + return 0;
> > +
> > + return count;
> > }
> > -device_initcall(hvc_sbi_init);
> >
> > -static int __init hvc_sbi_console_init(void)
> > +static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)
> > {
> > - hvc_instantiate(0, 0, &hvc_sbi_ops);
> > + phys_addr_t pa;
> > + struct sbiret ret;
> > +
> > + if (is_vmalloc_addr(buf)) {
> > + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> > + if (PAGE_SIZE < (offset_in_page(buf) + count))
> > + count = PAGE_SIZE - offset_in_page(buf);
> > + } else {
> > + pa = __pa(buf);
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_32BIT))
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> > + count, lower_32_bits(pa), upper_32_bits(pa),
> > + 0, 0, 0);
> > + else
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> > + count, pa, 0, 0, 0, 0);
>
> And here too.
Okay.
>
> thanks,
>
> greg k-h
Regards,
Anup
On Fri, Oct 20, 2023 at 12:51:39PM +0530, Anup Patel wrote:
> From: Atish Patra <atishp@rivosinc.com>
>
> RISC-V SBI specification supports advanced debug console
> support via SBI DBCN extension.
>
> Extend the HVC SBI driver to support it.
>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
> drivers/tty/hvc/Kconfig | 2 +-
> drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> 2 files changed, 76 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> index 4f9264d005c0..6e05c5c7bca1 100644
> --- a/drivers/tty/hvc/Kconfig
> +++ b/drivers/tty/hvc/Kconfig
> @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
>
> config HVC_RISCV_SBI
> bool "RISC-V SBI console support"
> - depends on RISCV_SBI_V01
> + depends on RISCV_SBI
> select HVC_DRIVER
> help
> This enables support for console output via RISC-V SBI calls, which
> diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> index 31f53fa77e4a..56da1a4b5aca 100644
> --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> return i;
> }
>
> -static const struct hv_ops hvc_sbi_ops = {
> +static const struct hv_ops hvc_sbi_v01_ops = {
> .get_chars = hvc_sbi_tty_get,
> .put_chars = hvc_sbi_tty_put,
> };
>
> -static int __init hvc_sbi_init(void)
> +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> {
> - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf)) {
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + if (PAGE_SIZE < (offset_in_page(buf) + count))
I thought checkpatch complained about uppercase constants being on the
left in comparisons.
> + count = PAGE_SIZE - offset_in_page(buf);
> + } else {
> + pa = __pa(buf);
> + }
> +
> + if (IS_ENABLED(CONFIG_32BIT))
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> + count, lower_32_bits(pa), upper_32_bits(pa),
> + 0, 0, 0);
> + else
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> + count, pa, 0, 0, 0, 0);
> + if (ret.error)
> + return 0;
> +
> + return count;
Shouldn't we return ret.value here in case it's less than count? I see we
already do that below in get().
> }
> -device_initcall(hvc_sbi_init);
>
> -static int __init hvc_sbi_console_init(void)
> +static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)
> {
> - hvc_instantiate(0, 0, &hvc_sbi_ops);
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf)) {
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + if (PAGE_SIZE < (offset_in_page(buf) + count))
> + count = PAGE_SIZE - offset_in_page(buf);
> + } else {
> + pa = __pa(buf);
> + }
> +
> + if (IS_ENABLED(CONFIG_32BIT))
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> + count, lower_32_bits(pa), upper_32_bits(pa),
> + 0, 0, 0);
> + else
> + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> + count, pa, 0, 0, 0, 0);
> + if (ret.error)
> + return 0;
> +
> + return ret.value;
> +}
> +
> +static const struct hv_ops hvc_sbi_dbcn_ops = {
> + .put_chars = hvc_sbi_dbcn_tty_put,
> + .get_chars = hvc_sbi_dbcn_tty_get,
> +};
> +
> +static int __init hvc_sbi_init(void)
> +{
> + int err;
> +
> + if ((sbi_spec_version >= sbi_mk_version(2, 0)) &&
> + (sbi_probe_extension(SBI_EXT_DBCN) > 0)) {
> + err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_dbcn_ops, 16));
Why an outbuf size of only 16?
> + if (err)
> + return err;
> + hvc_instantiate(0, 0, &hvc_sbi_dbcn_ops);
> + } else {
> + if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) {
> + err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_v01_ops, 16));
> + if (err)
> + return err;
> + hvc_instantiate(0, 0, &hvc_sbi_v01_ops);
> + } else {
> + return -ENODEV;
> + }
> + }
>
> return 0;
> }
> -console_initcall(hvc_sbi_console_init);
> +device_initcall(hvc_sbi_init);
> --
> 2.34.1
>
Thanks,
drew
On Fri, Oct 20, 2023 at 4:16 PM Andrew Jones <ajones@ventanamicro.com> wrote:
>
> On Fri, Oct 20, 2023 at 12:51:39PM +0530, Anup Patel wrote:
> > From: Atish Patra <atishp@rivosinc.com>
> >
> > RISC-V SBI specification supports advanced debug console
> > support via SBI DBCN extension.
> >
> > Extend the HVC SBI driver to support it.
> >
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > ---
> > drivers/tty/hvc/Kconfig | 2 +-
> > drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> > 2 files changed, 76 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> > index 4f9264d005c0..6e05c5c7bca1 100644
> > --- a/drivers/tty/hvc/Kconfig
> > +++ b/drivers/tty/hvc/Kconfig
> > @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
> >
> > config HVC_RISCV_SBI
> > bool "RISC-V SBI console support"
> > - depends on RISCV_SBI_V01
> > + depends on RISCV_SBI
> > select HVC_DRIVER
> > help
> > This enables support for console output via RISC-V SBI calls, which
> > diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> > index 31f53fa77e4a..56da1a4b5aca 100644
> > --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> > +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> > @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> > return i;
> > }
> >
> > -static const struct hv_ops hvc_sbi_ops = {
> > +static const struct hv_ops hvc_sbi_v01_ops = {
> > .get_chars = hvc_sbi_tty_get,
> > .put_chars = hvc_sbi_tty_put,
> > };
> >
> > -static int __init hvc_sbi_init(void)
> > +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> > {
> > - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> > + phys_addr_t pa;
> > + struct sbiret ret;
> > +
> > + if (is_vmalloc_addr(buf)) {
> > + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> > + if (PAGE_SIZE < (offset_in_page(buf) + count))
>
> I thought checkpatch complained about uppercase constants being on the
> left in comparisons.
Nope checkpatch does not complain about this.
>
> > + count = PAGE_SIZE - offset_in_page(buf);
> > + } else {
> > + pa = __pa(buf);
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_32BIT))
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> > + count, lower_32_bits(pa), upper_32_bits(pa),
> > + 0, 0, 0);
> > + else
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_WRITE,
> > + count, pa, 0, 0, 0, 0);
> > + if (ret.error)
> > + return 0;
> > +
> > + return count;
>
> Shouldn't we return ret.value here in case it's less than count? I see we
> already do that below in get().
Ahh, yes. Good catch, I will update.
>
> > }
> > -device_initcall(hvc_sbi_init);
> >
> > -static int __init hvc_sbi_console_init(void)
> > +static int hvc_sbi_dbcn_tty_get(uint32_t vtermno, char *buf, int count)
> > {
> > - hvc_instantiate(0, 0, &hvc_sbi_ops);
> > + phys_addr_t pa;
> > + struct sbiret ret;
> > +
> > + if (is_vmalloc_addr(buf)) {
> > + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> > + if (PAGE_SIZE < (offset_in_page(buf) + count))
> > + count = PAGE_SIZE - offset_in_page(buf);
> > + } else {
> > + pa = __pa(buf);
> > + }
> > +
> > + if (IS_ENABLED(CONFIG_32BIT))
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> > + count, lower_32_bits(pa), upper_32_bits(pa),
> > + 0, 0, 0);
> > + else
> > + ret = sbi_ecall(SBI_EXT_DBCN, SBI_EXT_DBCN_CONSOLE_READ,
> > + count, pa, 0, 0, 0, 0);
> > + if (ret.error)
> > + return 0;
> > +
> > + return ret.value;
> > +}
> > +
> > +static const struct hv_ops hvc_sbi_dbcn_ops = {
> > + .put_chars = hvc_sbi_dbcn_tty_put,
> > + .get_chars = hvc_sbi_dbcn_tty_get,
> > +};
> > +
> > +static int __init hvc_sbi_init(void)
> > +{
> > + int err;
> > +
> > + if ((sbi_spec_version >= sbi_mk_version(2, 0)) &&
> > + (sbi_probe_extension(SBI_EXT_DBCN) > 0)) {
> > + err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_dbcn_ops, 16));
>
> Why an outbuf size of only 16?
The output buffer size of 16 is a very common choice across
HVC drivers. The next best choice is 256.
I guess 256 is better so I will go with that.
>
> > + if (err)
> > + return err;
> > + hvc_instantiate(0, 0, &hvc_sbi_dbcn_ops);
> > + } else {
> > + if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) {
> > + err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_v01_ops, 16));
> > + if (err)
> > + return err;
> > + hvc_instantiate(0, 0, &hvc_sbi_v01_ops);
> > + } else {
> > + return -ENODEV;
> > + }
> > + }
> >
> > return 0;
> > }
> > -console_initcall(hvc_sbi_console_init);
> > +device_initcall(hvc_sbi_init);
> > --
> > 2.34.1
> >
>
> Thanks,
> drew
Regards,
Anup
Anup Patel <apatel@ventanamicro.com> writes:
> From: Atish Patra <atishp@rivosinc.com>
>
> RISC-V SBI specification supports advanced debug console
> support via SBI DBCN extension.
>
> Extend the HVC SBI driver to support it.
>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
> drivers/tty/hvc/Kconfig | 2 +-
> drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> 2 files changed, 76 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> index 4f9264d005c0..6e05c5c7bca1 100644
> --- a/drivers/tty/hvc/Kconfig
> +++ b/drivers/tty/hvc/Kconfig
> @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
>
> config HVC_RISCV_SBI
> bool "RISC-V SBI console support"
> - depends on RISCV_SBI_V01
> + depends on RISCV_SBI
> select HVC_DRIVER
> help
> This enables support for console output via RISC-V SBI calls, which
> diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> index 31f53fa77e4a..56da1a4b5aca 100644
> --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> return i;
> }
>
> -static const struct hv_ops hvc_sbi_ops = {
> +static const struct hv_ops hvc_sbi_v01_ops = {
> .get_chars = hvc_sbi_tty_get,
> .put_chars = hvc_sbi_tty_put,
> };
>
> -static int __init hvc_sbi_init(void)
> +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> {
> - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> + phys_addr_t pa;
> + struct sbiret ret;
> +
> + if (is_vmalloc_addr(buf)) {
> + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> + if (PAGE_SIZE < (offset_in_page(buf) + count))
> + count = PAGE_SIZE - offset_in_page(buf);
Thanks for fixing the cross-page issue. Now you're cutting the buffer
off. What about doing two SBI calls instead? (Dito on the get side)
Björn
On Fri, Oct 20, 2023 at 3:25 PM Björn Töpel <bjorn@kernel.org> wrote:
>
> Anup Patel <apatel@ventanamicro.com> writes:
>
> > From: Atish Patra <atishp@rivosinc.com>
> >
> > RISC-V SBI specification supports advanced debug console
> > support via SBI DBCN extension.
> >
> > Extend the HVC SBI driver to support it.
> >
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> > Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> > ---
> > drivers/tty/hvc/Kconfig | 2 +-
> > drivers/tty/hvc/hvc_riscv_sbi.c | 82 ++++++++++++++++++++++++++++++---
> > 2 files changed, 76 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
> > index 4f9264d005c0..6e05c5c7bca1 100644
> > --- a/drivers/tty/hvc/Kconfig
> > +++ b/drivers/tty/hvc/Kconfig
> > @@ -108,7 +108,7 @@ config HVC_DCC_SERIALIZE_SMP
> >
> > config HVC_RISCV_SBI
> > bool "RISC-V SBI console support"
> > - depends on RISCV_SBI_V01
> > + depends on RISCV_SBI
> > select HVC_DRIVER
> > help
> > This enables support for console output via RISC-V SBI calls, which
> > diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
> > index 31f53fa77e4a..56da1a4b5aca 100644
> > --- a/drivers/tty/hvc/hvc_riscv_sbi.c
> > +++ b/drivers/tty/hvc/hvc_riscv_sbi.c
> > @@ -39,21 +39,89 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
> > return i;
> > }
> >
> > -static const struct hv_ops hvc_sbi_ops = {
> > +static const struct hv_ops hvc_sbi_v01_ops = {
> > .get_chars = hvc_sbi_tty_get,
> > .put_chars = hvc_sbi_tty_put,
> > };
> >
> > -static int __init hvc_sbi_init(void)
> > +static int hvc_sbi_dbcn_tty_put(uint32_t vtermno, const char *buf, int count)
> > {
> > - return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
> > + phys_addr_t pa;
> > + struct sbiret ret;
> > +
> > + if (is_vmalloc_addr(buf)) {
> > + pa = page_to_phys(vmalloc_to_page(buf)) + offset_in_page(buf);
> > + if (PAGE_SIZE < (offset_in_page(buf) + count))
> > + count = PAGE_SIZE - offset_in_page(buf);
>
> Thanks for fixing the cross-page issue. Now you're cutting the buffer
> off. What about doing two SBI calls instead? (Dito on the get side)
We don't need to handle that because the hvc_console framework
will ensure remaining characters are sent-out. Same applies to
get side as well.
Regards,
Anup
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