diff options
| author | Atish Patra <[email protected]> | 2019-01-20 23:24:26 -0800 |
|---|---|---|
| committer | Anup Patel <[email protected]> | 2019-01-22 10:03:49 +0530 |
| commit | b9c517f5593716d11013bef5fa25f037734327b7 (patch) | |
| tree | 73113d448ccb1503ad3d4e0ed366be216988a589 | |
| parent | 312b6bf32f51e530dd22746fe2a36d6459e29588 (diff) | |
lib: Fix ipi type update
IPIs are updated in scratch space by source hart.
However, different harts or same hart may want to
send different IPIs before previous IPI was read
by the target hart. Currently, previous IPI type
is overwritten in that case.
Use atomic bit set/clear operations to update IPIs.
Signed-off-by: Atish Patra <[email protected]>
| -rw-r--r-- | lib/sbi_ipi.c | 43 |
1 files changed, 27 insertions, 16 deletions
diff --git a/lib/sbi_ipi.c b/lib/sbi_ipi.c index 423a9a09..1b740706 100644 --- a/lib/sbi_ipi.c +++ b/lib/sbi_ipi.c @@ -9,7 +9,10 @@ #include <sbi/riscv_asm.h> #include <sbi/riscv_barrier.h> +#include <sbi/riscv_atomic.h> #include <sbi/sbi_hart.h> +#include <sbi/sbi_bitops.h> +#include <sbi/sbi_console.h> #include <sbi/sbi_ipi.h> #include <sbi/sbi_platform.h> #include <sbi/sbi_timer.h> @@ -30,7 +33,7 @@ int sbi_ipi_send_many(struct sbi_scratch *scratch, for (i = 0, m = mask; m; i++, m >>= 1) { if ((m & 1) && (i != hartid) && !sbi_platform_hart_disabled(plat, hartid)) { oth = sbi_hart_id_to_scratch(scratch, i); - oth->ipi_type = event; + atomic_raw_set_bit(event, &oth->ipi_type); mb(); sbi_platform_ipi_inject(plat, i, hartid); if (event != SBI_IPI_EVENT_SOFT) @@ -49,23 +52,31 @@ void sbi_ipi_clear_smode(struct sbi_scratch *scratch, u32 hartid) void sbi_ipi_process(struct sbi_scratch *scratch, u32 hartid) { struct sbi_platform *plat = sbi_platform_ptr(scratch); + volatile unsigned long ipi_type; + unsigned int ipi_event; sbi_platform_ipi_clear(plat, hartid); - switch (scratch->ipi_type) { - case SBI_IPI_EVENT_SOFT: - csr_set(mip, MIP_SSIP); - break; - case SBI_IPI_EVENT_FENCE_I: - __asm__ __volatile("fence.i"); - break; - case SBI_IPI_EVENT_SFENCE_VMA: - __asm__ __volatile("sfence.vma"); - break; - case SBI_IPI_EVENT_HALT: - sbi_hart_hang(); - break; - }; - scratch->ipi_type = 0; + + do { + ipi_type = scratch->ipi_type; + rmb(); + ipi_event = __ffs(ipi_type); + switch (ipi_event) { + case SBI_IPI_EVENT_SOFT: + csr_set(mip, MIP_SSIP); + break; + case SBI_IPI_EVENT_FENCE_I: + __asm__ __volatile("fence.i"); + break; + case SBI_IPI_EVENT_SFENCE_VMA: + __asm__ __volatile("sfence.vma"); + break; + case SBI_IPI_EVENT_HALT: + sbi_hart_hang(); + break; + }; + ipi_type = atomic_raw_clear_bit(ipi_event, &scratch->ipi_type); + } while(ipi_type > 0); } int sbi_ipi_init(struct sbi_scratch *scratch, u32 hartid, bool cold_boot) |