At present the SiFive PLIC model "priority-base" expects interrupt priority register base starting from source 1 instead source 0, that's why on most platforms "priority-base" is set to 0x04 except 'opentitan' machine. 'opentitan' should have set "priority-base" to 0x04 too.
Note the irq number calculation in sifive_plic_{read,write} is correct as the codes make up for the irq number by adding 1. Let's simply update "priority-base" to start from interrupt source 0 and add a comment to make it crystal clear. Signed-off-by: Bin Meng <bm...@tinylab.org> --- include/hw/riscv/microchip_pfsoc.h | 2 +- include/hw/riscv/shakti_c.h | 2 +- include/hw/riscv/sifive_e.h | 2 +- include/hw/riscv/sifive_u.h | 2 +- include/hw/riscv/virt.h | 2 +- hw/intc/sifive_plic.c | 5 +++-- 6 files changed, 8 insertions(+), 7 deletions(-) diff --git a/include/hw/riscv/microchip_pfsoc.h b/include/hw/riscv/microchip_pfsoc.h index 9720bac2d5..c10d87a601 100644 --- a/include/hw/riscv/microchip_pfsoc.h +++ b/include/hw/riscv/microchip_pfsoc.h @@ -152,7 +152,7 @@ enum { #define MICROCHIP_PFSOC_PLIC_NUM_SOURCES 187 #define MICROCHIP_PFSOC_PLIC_NUM_PRIORITIES 7 -#define MICROCHIP_PFSOC_PLIC_PRIORITY_BASE 0x04 +#define MICROCHIP_PFSOC_PLIC_PRIORITY_BASE 0x00 #define MICROCHIP_PFSOC_PLIC_PENDING_BASE 0x1000 #define MICROCHIP_PFSOC_PLIC_ENABLE_BASE 0x2000 #define MICROCHIP_PFSOC_PLIC_ENABLE_STRIDE 0x80 diff --git a/include/hw/riscv/shakti_c.h b/include/hw/riscv/shakti_c.h index daf0aae13f..539fe1156d 100644 --- a/include/hw/riscv/shakti_c.h +++ b/include/hw/riscv/shakti_c.h @@ -65,7 +65,7 @@ enum { #define SHAKTI_C_PLIC_NUM_SOURCES 28 /* Excluding Priority 0 */ #define SHAKTI_C_PLIC_NUM_PRIORITIES 2 -#define SHAKTI_C_PLIC_PRIORITY_BASE 0x04 +#define SHAKTI_C_PLIC_PRIORITY_BASE 0x00 #define SHAKTI_C_PLIC_PENDING_BASE 0x1000 #define SHAKTI_C_PLIC_ENABLE_BASE 0x2000 #define SHAKTI_C_PLIC_ENABLE_STRIDE 0x80 diff --git a/include/hw/riscv/sifive_e.h b/include/hw/riscv/sifive_e.h index 9e58247fd8..b824a79e2d 100644 --- a/include/hw/riscv/sifive_e.h +++ b/include/hw/riscv/sifive_e.h @@ -89,7 +89,7 @@ enum { */ #define SIFIVE_E_PLIC_NUM_SOURCES 53 #define SIFIVE_E_PLIC_NUM_PRIORITIES 7 -#define SIFIVE_E_PLIC_PRIORITY_BASE 0x04 +#define SIFIVE_E_PLIC_PRIORITY_BASE 0x00 #define SIFIVE_E_PLIC_PENDING_BASE 0x1000 #define SIFIVE_E_PLIC_ENABLE_BASE 0x2000 #define SIFIVE_E_PLIC_ENABLE_STRIDE 0x80 diff --git a/include/hw/riscv/sifive_u.h b/include/hw/riscv/sifive_u.h index 8f63a183c4..e680d61ece 100644 --- a/include/hw/riscv/sifive_u.h +++ b/include/hw/riscv/sifive_u.h @@ -158,7 +158,7 @@ enum { #define SIFIVE_U_PLIC_NUM_SOURCES 54 #define SIFIVE_U_PLIC_NUM_PRIORITIES 7 -#define SIFIVE_U_PLIC_PRIORITY_BASE 0x04 +#define SIFIVE_U_PLIC_PRIORITY_BASE 0x00 #define SIFIVE_U_PLIC_PENDING_BASE 0x1000 #define SIFIVE_U_PLIC_ENABLE_BASE 0x2000 #define SIFIVE_U_PLIC_ENABLE_STRIDE 0x80 diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h index 7c23aea4a0..37819c168c 100644 --- a/include/hw/riscv/virt.h +++ b/include/hw/riscv/virt.h @@ -99,7 +99,7 @@ enum { #define VIRT_IRQCHIP_MAX_GUESTS_BITS 3 #define VIRT_IRQCHIP_MAX_GUESTS ((1U << VIRT_IRQCHIP_MAX_GUESTS_BITS) - 1U) -#define VIRT_PLIC_PRIORITY_BASE 0x04 +#define VIRT_PLIC_PRIORITY_BASE 0x00 #define VIRT_PLIC_PENDING_BASE 0x1000 #define VIRT_PLIC_ENABLE_BASE 0x2000 #define VIRT_PLIC_ENABLE_STRIDE 0x80 diff --git a/hw/intc/sifive_plic.c b/hw/intc/sifive_plic.c index 2bd292410d..7a6a358c57 100644 --- a/hw/intc/sifive_plic.c +++ b/hw/intc/sifive_plic.c @@ -140,7 +140,7 @@ static uint64_t sifive_plic_read(void *opaque, hwaddr addr, unsigned size) SiFivePLICState *plic = opaque; if (addr_between(addr, plic->priority_base, plic->num_sources << 2)) { - uint32_t irq = ((addr - plic->priority_base) >> 2) + 1; + uint32_t irq = (addr - plic->priority_base) >> 2; return plic->source_priority[irq]; } else if (addr_between(addr, plic->pending_base, plic->num_sources >> 3)) { @@ -187,7 +187,7 @@ static void sifive_plic_write(void *opaque, hwaddr addr, uint64_t value, SiFivePLICState *plic = opaque; if (addr_between(addr, plic->priority_base, plic->num_sources << 2)) { - uint32_t irq = ((addr - plic->priority_base) >> 2) + 1; + uint32_t irq = (addr - plic->priority_base) >> 2; if (((plic->num_priorities + 1) & plic->num_priorities) == 0) { /* @@ -428,6 +428,7 @@ static Property sifive_plic_properties[] = { /* number of interrupt sources including interrupt source 0 */ DEFINE_PROP_UINT32("num-sources", SiFivePLICState, num_sources, 1), DEFINE_PROP_UINT32("num-priorities", SiFivePLICState, num_priorities, 0), + /* interrupt priority register base starting from source 0 */ DEFINE_PROP_UINT32("priority-base", SiFivePLICState, priority_base, 0), DEFINE_PROP_UINT32("pending-base", SiFivePLICState, pending_base, 0), DEFINE_PROP_UINT32("enable-base", SiFivePLICState, enable_base, 0), -- 2.34.1