diff options
author | Samuel Holland <samuel@sholland.org> | 2022-06-13 04:03:52 +0300 |
---|---|---|
committer | Anup Patel <anup@brainfault.org> | 2022-06-13 09:24:06 +0300 |
commit | 2b79b694a80513696daf072db0fd980e7573b212 (patch) | |
tree | 7e64f4ba642d226c35a0726f35841ed23bdb5644 | |
parent | 415ecf28f7ade7ba5a48a0cc9be8d45a7539dd89 (diff) | |
download | opensbi-2b79b694a80513696daf072db0fd980e7573b212.tar.xz |
lib: irqchip/plic: Add priority save/restore helpers
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.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
-rw-r--r-- | include/sbi_utils/irqchip/plic.h | 5 | ||||
-rw-r--r-- | lib/utils/irqchip/plic.c | 19 |
2 files changed, 24 insertions, 0 deletions
diff --git a/include/sbi_utils/irqchip/plic.h b/include/sbi_utils/irqchip/plic.h index 21b2266..48c24f0 100644 --- a/include/sbi_utils/irqchip/plic.h +++ b/include/sbi_utils/irqchip/plic.h @@ -17,6 +17,11 @@ struct plic_data { unsigned long num_src; }; +/* So far, priorities on all consumers of these functions fit in 8 bits. */ +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..8c25b9d 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 +36,18 @@ static void plic_set_priority(const struct plic_data *plic, u32 source, u32 val) writel(val, plic_priority); } +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; |