[PATCH 4/5] lib: sbi: Extend hart protection abstraction to allow ID configuration
Rahul Pathak
rahul.pathak at oss.qualcomm.com
Wed Jul 22 04:22:28 PDT 2026
On Fri, Jul 17, 2026 at 1:15 PM Anup Patel <anup.patel at oss.qualcomm.com> wrote:
>
> There are various ID configuration ISA extensions such as RISC-V Worlds,
> Supervisor domain ID, QoS ID, etc which need to be re-configured upon
> domain context switch on a hart. Extend hart protection abstraction to
> support both memory protection and ID configuration ISA extensions.
>
> Signed-off-by: Anup Patel <anup.patel at oss.qualcomm.com>
> ---
> include/sbi/sbi_hart_protection.h | 16 +++++-
> lib/sbi/sbi_hart_pmp.c | 2 +
> lib/sbi/sbi_hart_protection.c | 94 ++++++++++++++++++++++++++-----
> lib/sbi/sbi_init.c | 2 +-
> platform/generic/eswin/eic770x.c | 1 +
> 5 files changed, 98 insertions(+), 17 deletions(-)
>
> diff --git a/include/sbi/sbi_hart_protection.h b/include/sbi/sbi_hart_protection.h
> index 5e170f05..1358b5be 100644
> --- a/include/sbi/sbi_hart_protection.h
> +++ b/include/sbi/sbi_hart_protection.h
> @@ -13,6 +13,13 @@
> struct sbi_scratch;
> struct sbi_domain;
>
> +/** Different types of hart protection mechanisms */
> +enum sbi_hart_protection_type {
> + SBI_HART_PROTECTION_TYPE_MEMORY = 0,
> + SBI_HART_PROTECTION_TYPE_ID,
> + SBI_HART_PROTECTIOn_TYPE_MAX
Typo here "n"
> +};
> +
> /** Representation of hart protection mechanism */
> struct sbi_hart_protection {
> /** List head */
> @@ -21,6 +28,9 @@ struct sbi_hart_protection {
> /** Name of the hart protection mechanism */
> char name[32];
>
> + /** Type of the hart protection mechanism */
> + enum sbi_hart_protection_type type;
> +
> /** Ratings of the hart protection mechanism (higher is better) */
> unsigned long rating;
>
> @@ -40,11 +50,11 @@ struct sbi_hart_protection {
> };
>
> /**
> - * Get the best hart protection mechanism
> + * Get the best hart memory protection mechanism
> *
> - * @return pointer to best hart protection mechanism
> + * @return pointer to best hart memory protection mechanism
> */
> -struct sbi_hart_protection *sbi_hart_protection_best(void);
> +struct sbi_hart_protection *sbi_hart_memory_protection_best(void);
>
> /**
> * Register a hart protection mechanism
> diff --git a/lib/sbi/sbi_hart_pmp.c b/lib/sbi/sbi_hart_pmp.c
> index 5ede3cc1..c0a4ce1b 100644
> --- a/lib/sbi/sbi_hart_pmp.c
> +++ b/lib/sbi/sbi_hart_pmp.c
> @@ -425,6 +425,7 @@ static void sbi_hart_pmp_unconfigure(struct sbi_scratch *scratch,
> static struct sbi_hart_protection pmp_protection = {
> .name = "pmp",
> .rating = 100,
> + .type = SBI_HART_PROTECTION_TYPE_MEMORY,
> .configure = sbi_hart_oldpmp_configure,
> .unconfigure = sbi_hart_pmp_unconfigure,
> };
> @@ -432,6 +433,7 @@ static struct sbi_hart_protection pmp_protection = {
> static struct sbi_hart_protection epmp_protection = {
> .name = "epmp",
> .rating = 200,
> + .type = SBI_HART_PROTECTION_TYPE_MEMORY,
> .configure = sbi_hart_smepmp_configure,
> .unconfigure = sbi_hart_pmp_unconfigure,
> .map_range = sbi_hart_smepmp_map_range,
> diff --git a/lib/sbi/sbi_hart_protection.c b/lib/sbi/sbi_hart_protection.c
> index fecefde8..d31e9938 100644
> --- a/lib/sbi/sbi_hart_protection.c
> +++ b/lib/sbi/sbi_hart_protection.c
> @@ -10,12 +10,16 @@
>
> static SBI_LIST_HEAD(hart_protection_list);
>
> -struct sbi_hart_protection *sbi_hart_protection_best(void)
> +struct sbi_hart_protection *sbi_hart_memory_protection_best(void)
> {
> - if (sbi_list_empty(&hart_protection_list))
> - return NULL;
> + struct sbi_hart_protection *pos;
>
> - return sbi_list_first_entry(&hart_protection_list, struct sbi_hart_protection, head);
> + sbi_list_for_each_entry(pos, &hart_protection_list, head) {
> + if (pos->type == SBI_HART_PROTECTION_TYPE_MEMORY)
> + return pos;
> + }
> +
> + return NULL;
> }
>
> int sbi_hart_protection_register(struct sbi_hart_protection *hprot)
> @@ -74,33 +78,97 @@ static void __hart_protection_unconfigure(struct sbi_scratch *scratch,
> int sbi_hart_protection_configure(struct sbi_scratch *scratch,
> struct sbi_domain *dom)
> {
> - return __hart_protection_configure(scratch, sbi_hart_protection_best(), dom);
> + bool do_configure, memory_protect_done = false;
> + struct sbi_hart_protection *hprot;
> + int ret;
> +
> + sbi_list_for_each_entry(hprot, &hart_protection_list, head) {
> + do_configure = false;
> + switch (hprot->type) {
While reading the code found that hprot->type checking is not done
in the early stage in sbi_hart_protection_register itself. If firmware
has to explicitly check and fail upon invalid type then why not fail
while registering the protection mechanism itself.
> + case SBI_HART_PROTECTION_TYPE_MEMORY:
> + do_configure = !memory_protect_done;
> + memory_protect_done = true;
> + break;
> + case SBI_HART_PROTECTION_TYPE_ID:
> + do_configure = true;
> + break;
> + default:
> + break;
> + }
> + if (!do_configure)
> + continue;
> +
> + ret = __hart_protection_configure(scratch, hprot, dom);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> }
>
> void sbi_hart_protection_unconfigure(struct sbi_scratch *scratch,
> struct sbi_domain *dom)
> {
> - __hart_protection_unconfigure(scratch, sbi_hart_protection_best(), dom);
> +
> + bool do_unconfigure, memory_protect_done = false;
> + struct sbi_hart_protection *hprot;
> +
> + sbi_list_for_each_entry(hprot, &hart_protection_list, head) {
> + do_unconfigure = false;
> + switch (hprot->type) {
> + case SBI_HART_PROTECTION_TYPE_MEMORY:
> + do_unconfigure = !memory_protect_done;
> + memory_protect_done = true;
> + break;
> + case SBI_HART_PROTECTION_TYPE_ID:
> + do_unconfigure = true;
> + break;
> + default:
> + break;
> + }
> + if (!do_unconfigure)
> + continue;
> +
> + __hart_protection_unconfigure(scratch, hprot, dom);
> + }
> }
>
> int sbi_hart_protection_reconfigure(struct sbi_scratch *scratch,
> struct sbi_domain *current_dom,
> struct sbi_domain *next_dom)
> {
> - struct sbi_hart_protection *hprot = sbi_hart_protection_best();
> + bool do_reconfigure, memory_protect_done = false;
> + struct sbi_hart_protection *hprot;
> int ret;
>
> - __hart_protection_unconfigure(scratch, hprot, current_dom);
> - ret = __hart_protection_configure(scratch, hprot, next_dom);
> - if (ret)
> - return ret;
> + sbi_list_for_each_entry(hprot, &hart_protection_list, head) {
> + do_reconfigure = false;
> + switch (hprot->type) {
> + case SBI_HART_PROTECTION_TYPE_MEMORY:
> + do_reconfigure = !memory_protect_done;
> + memory_protect_done = true;
> + break;
> + case SBI_HART_PROTECTION_TYPE_ID:
> + do_reconfigure = true;
> + break;
> + default:
> + break;
> + }
> + if (!do_reconfigure)
> + continue;
> +
> + __hart_protection_unconfigure(scratch, hprot, current_dom);
> + ret = __hart_protection_configure(scratch, hprot, next_dom);
> + if (ret)
> + return ret;
> + }
>
> return 0;
> }
>
> int sbi_hart_protection_map_range(unsigned long base, unsigned long size)
> {
> - struct sbi_hart_protection *hprot = sbi_hart_protection_best();
> + struct sbi_hart_protection *hprot = sbi_hart_memory_protection_best();
>
> if (!hprot || !hprot->map_range)
> return 0;
> @@ -110,7 +178,7 @@ int sbi_hart_protection_map_range(unsigned long base, unsigned long size)
>
> int sbi_hart_protection_unmap_range(unsigned long base, unsigned long size)
> {
> - struct sbi_hart_protection *hprot = sbi_hart_protection_best();
> + struct sbi_hart_protection *hprot = sbi_hart_memory_protection_best();
>
> if (!hprot || !hprot->unmap_range)
> return 0;
> diff --git a/lib/sbi/sbi_init.c b/lib/sbi/sbi_init.c
> index d74dc67c..3f1f136a 100644
> --- a/lib/sbi/sbi_init.c
> +++ b/lib/sbi/sbi_init.c
> @@ -93,7 +93,7 @@ static void sbi_boot_print_general(struct sbi_scratch *scratch)
> sbi_printf("Platform Features : %s\n", str);
> sbi_printf("Platform HART Count : %u\n",
> sbi_platform_hart_count(plat));
> - hprot = sbi_hart_protection_best();
> + hprot = sbi_hart_memory_protection_best();
> sbi_printf("Platform HART Protection : %s\n",
> (hprot) ? hprot->name : "---");
> idev = sbi_ipi_get_device();
> diff --git a/platform/generic/eswin/eic770x.c b/platform/generic/eswin/eic770x.c
> index da4d0e34..c71198a8 100644
> --- a/platform/generic/eswin/eic770x.c
> +++ b/platform/generic/eswin/eic770x.c
> @@ -470,6 +470,7 @@ static void eswin_eic7700_pmp_unconfigure(struct sbi_scratch *scratch,
> static struct sbi_hart_protection eswin_eic7700_pmp_protection = {
> .name = "eic7700_pmp",
> .rating = -1UL,
> + .type = SBI_HART_PROTECTION_TYPE_MEMORY,
> .configure = eswin_eic7700_pmp_configure,
> .unconfigure = eswin_eic7700_pmp_unconfigure,
> };
> --
> 2.43.0
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi
More information about the opensbi
mailing list