diff mbox series

[RFC,v2,6/9] lib: irqchip/plic: Add priority save/restore helpers

Message ID 20220530033738.27127-7-samuel@sholland.org
State Superseded
Headers show
Series HSM implementation for Allwinner D1 | expand

Commit Message

Samuel Holland May 30, 2022, 3:37 a.m. UTC 
These can be used by platform code to save the PLIC priority state, if
it would otherwise be lost during non-retentive suspend. The platform
is responsible for allocating all necessary storage.

As a space optimization, store the saved priority values as 8-bit
integers, since that is large enough to hold any priority value on the
relevant platforms.

Signed-off-by: Samuel Holland <samuel@sholland.org>
---

Changes in v2:
 - New patch for v2

 include/sbi_utils/irqchip/plic.h |  4 ++++
 lib/utils/irqchip/plic.c         | 20 ++++++++++++++++++++
 2 files changed, 24 insertions(+)

Comments

Anup Patel June 1, 2022, 1 p.m. UTC | #1 
On Mon, May 30, 2022 at 9:07 AM Samuel Holland <samuel@sholland.org> wrote:
>
> These can be used by platform code to save the PLIC priority state, if
> it would otherwise be lost during non-retentive suspend. The platform
> is responsible for allocating all necessary storage.
>
> As a space optimization, store the saved priority values as 8-bit
> integers, since that is large enough to hold any priority value on the
> relevant platforms.
>
> Signed-off-by: Samuel Holland <samuel@sholland.org>

Looks good to me.

Reviewed-by: Anup Patel <anup@brainfault.org>

Regards,
Anup

> ---
>
> Changes in v2:
>  - New patch for v2
>
>  include/sbi_utils/irqchip/plic.h |  4 ++++
>  lib/utils/irqchip/plic.c         | 20 ++++++++++++++++++++
>  2 files changed, 24 insertions(+)
>
> diff --git a/include/sbi_utils/irqchip/plic.h b/include/sbi_utils/irqchip/plic.h
> index 21b2266..566fd7a 100644
> --- a/include/sbi_utils/irqchip/plic.h
> +++ b/include/sbi_utils/irqchip/plic.h
> @@ -17,6 +17,10 @@ struct plic_data {
>         unsigned long num_src;
>  };
>
> +void plic_priority_save(const struct plic_data *plic, u8 *priority);
> +
> +void plic_priority_restore(const struct plic_data *plic, const u8 *priority);
> +
>  void plic_context_save(const struct plic_data *plic, int context_id,
>                        u32 *enable, u32 *threshold);
>
> diff --git a/lib/utils/irqchip/plic.c b/lib/utils/irqchip/plic.c
> index 0c64078..b0329b8 100644
> --- a/lib/utils/irqchip/plic.c
> +++ b/lib/utils/irqchip/plic.c
> @@ -22,6 +22,13 @@
>  #define PLIC_CONTEXT_BASE 0x200000
>  #define PLIC_CONTEXT_STRIDE 0x1000
>
> +static u32 plic_get_priority(const struct plic_data *plic, u32 source)
> +{
> +       volatile void *plic_priority = (char *)plic->addr +
> +                       PLIC_PRIORITY_BASE + 4 * source;
> +       return readl(plic_priority);
> +}
> +
>  static void plic_set_priority(const struct plic_data *plic, u32 source, u32 val)
>  {
>         volatile void *plic_priority = (char *)plic->addr +
> @@ -29,6 +36,19 @@ static void plic_set_priority(const struct plic_data *plic, u32 source, u32 val)
>         writel(val, plic_priority);
>  }
>
> +/* So far, priorities on all consumers of these functions fit in 8 bits. */
> +void plic_priority_save(const struct plic_data *plic, u8 *priority)
> +{
> +       for (u32 i = 0; i < plic->num_src; i++)
> +               priority[i] = plic_get_priority(plic, i);
> +}
> +
> +void plic_priority_restore(const struct plic_data *plic, const u8 *priority)
> +{
> +       for (u32 i = 0; i < plic->num_src; i++)
> +               plic_set_priority(plic, i, priority[i]);
> +}
> +
>  static u32 plic_get_thresh(const struct plic_data *plic, u32 cntxid)
>  {
>         volatile void *plic_thresh;
> --
> 2.35.1
>
>
> --
> opensbi mailing list
> opensbi@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi
diff mbox series

Patch

diff --git a/include/sbi_utils/irqchip/plic.h b/include/sbi_utils/irqchip/plic.h
index 21b2266..566fd7a 100644
--- a/include/sbi_utils/irqchip/plic.h
+++ b/include/sbi_utils/irqchip/plic.h
@@ -17,6 +17,10 @@  struct plic_data {
 	unsigned long num_src;
 };
 
+void plic_priority_save(const struct plic_data *plic, u8 *priority);
+
+void plic_priority_restore(const struct plic_data *plic, const u8 *priority);
+
 void plic_context_save(const struct plic_data *plic, int context_id,
 		       u32 *enable, u32 *threshold);
 
diff --git a/lib/utils/irqchip/plic.c b/lib/utils/irqchip/plic.c
index 0c64078..b0329b8 100644
--- a/lib/utils/irqchip/plic.c
+++ b/lib/utils/irqchip/plic.c
@@ -22,6 +22,13 @@ 
 #define PLIC_CONTEXT_BASE 0x200000
 #define PLIC_CONTEXT_STRIDE 0x1000
 
+static u32 plic_get_priority(const struct plic_data *plic, u32 source)
+{
+	volatile void *plic_priority = (char *)plic->addr +
+			PLIC_PRIORITY_BASE + 4 * source;
+	return readl(plic_priority);
+}
+
 static void plic_set_priority(const struct plic_data *plic, u32 source, u32 val)
 {
 	volatile void *plic_priority = (char *)plic->addr +
@@ -29,6 +36,19 @@  static void plic_set_priority(const struct plic_data *plic, u32 source, u32 val)
 	writel(val, plic_priority);
 }
 
+/* So far, priorities on all consumers of these functions fit in 8 bits. */
+void plic_priority_save(const struct plic_data *plic, u8 *priority)
+{
+	for (u32 i = 0; i < plic->num_src; i++)
+		priority[i] = plic_get_priority(plic, i);
+}
+
+void plic_priority_restore(const struct plic_data *plic, const u8 *priority)
+{
+	for (u32 i = 0; i < plic->num_src; i++)
+		plic_set_priority(plic, i, priority[i]);
+}
+
 static u32 plic_get_thresh(const struct plic_data *plic, u32 cntxid)
 {
 	volatile void *plic_thresh;