diff options
| author | Heiko Stuebner <heiko@sntech.de> | 2022-10-12 01:18:41 +0200 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2022-10-27 14:35:20 -0700 |
| commit | 65e9fb081877a18c432c6ff344937b7277c044b5 (patch) | |
| tree | 26a5470b97356f9b5e29f5fb4dfc34ef703af484 /arch/riscv/include/asm/errata_list.h | |
| parent | 5e9c68ea777594a2d63fa44c0509782e90821707 (diff) | |
drivers/perf: riscv_pmu_sbi: add support for PMU variant on T-Head C9xx cores
With the T-HEAD C9XX cores being designed before or during the ratification
to the SSCOFPMF extension, it implements functionality very similar but
not equal to it.
It implements overflow handling and also some privilege-mode filtering.
While SSCOFPMF supports this for all modes, the C9XX only implements the
filtering for M-mode and S-mode but not user-mode.
So add some adaptions to allow the C9XX to still handle
its PMU through the regular SBI PMU interface instead of defining new
interfaces or drivers.
To work properly, this requires a matching change in SBI, though the actual
interface between kernel and SBI does not change.
The main differences are a the overflow CSR and irq number.
As the reading of the overflow-csr is in the hot-path during irq handling,
use an errata and alternatives to not introduce new conditionals there.
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/all/20221011231841.2951264-2-heiko@sntech.de/
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/include/asm/errata_list.h')
| -rw-r--r-- | arch/riscv/include/asm/errata_list.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/arch/riscv/include/asm/errata_list.h b/arch/riscv/include/asm/errata_list.h index 19a771085781..4180312d2a70 100644 --- a/arch/riscv/include/asm/errata_list.h +++ b/arch/riscv/include/asm/errata_list.h @@ -6,6 +6,7 @@ #define ASM_ERRATA_LIST_H #include <asm/alternative.h> +#include <asm/csr.h> #include <asm/vendorid_list.h> #ifdef CONFIG_ERRATA_SIFIVE @@ -17,7 +18,8 @@ #ifdef CONFIG_ERRATA_THEAD #define ERRATA_THEAD_PBMT 0 #define ERRATA_THEAD_CMO 1 -#define ERRATA_THEAD_NUMBER 2 +#define ERRATA_THEAD_PMU 2 +#define ERRATA_THEAD_NUMBER 3 #endif #define CPUFEATURE_SVPBMT 0 @@ -142,6 +144,18 @@ asm volatile(ALTERNATIVE_2( \ "r"((unsigned long)(_start) + (_size)) \ : "a0") +#define THEAD_C9XX_RV_IRQ_PMU 17 +#define THEAD_C9XX_CSR_SCOUNTEROF 0x5c5 + +#define ALT_SBI_PMU_OVERFLOW(__ovl) \ +asm volatile(ALTERNATIVE( \ + "csrr %0, " __stringify(CSR_SSCOUNTOVF), \ + "csrr %0, " __stringify(THEAD_C9XX_CSR_SCOUNTEROF), \ + THEAD_VENDOR_ID, ERRATA_THEAD_PMU, \ + CONFIG_ERRATA_THEAD_PMU) \ + : "=r" (__ovl) : \ + : "memory") + #endif /* __ASSEMBLY__ */ #endif |