From: Tomasz Jeznach <tjeznach@rivosinc.com>
DBG support adds three additional registers: tr_req_iova, tr_req_ctl and
tr_response.
The DBG cap is always enabled. No on/off toggle is provided for it.
Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241016204038.649340-11-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
---
hw/riscv/riscv-iommu-bits.h | 17 +++++++++++
hw/riscv/riscv-iommu.c | 59 +++++++++++++++++++++++++++++++++++++
2 files changed, 76 insertions(+)
diff --git a/hw/riscv/riscv-iommu-bits.h b/hw/riscv/riscv-iommu-bits.h
index 96a994b9aa..6359ae0353 100644
--- a/hw/riscv/riscv-iommu-bits.h
+++ b/hw/riscv/riscv-iommu-bits.h
@@ -82,6 +82,7 @@ struct riscv_iommu_pq_record {
#define RISCV_IOMMU_CAP_ATS BIT_ULL(25)
#define RISCV_IOMMU_CAP_T2GPA BIT_ULL(26)
#define RISCV_IOMMU_CAP_IGS GENMASK_ULL(29, 28)
+#define RISCV_IOMMU_CAP_DBG BIT_ULL(31)
#define RISCV_IOMMU_CAP_PAS GENMASK_ULL(37, 32)
#define RISCV_IOMMU_CAP_PD8 BIT_ULL(38)
#define RISCV_IOMMU_CAP_PD17 BIT_ULL(39)
@@ -184,6 +185,22 @@ enum {
RISCV_IOMMU_INTR_COUNT
};
+/* 5.24 Translation request IOVA (64bits) */
+#define RISCV_IOMMU_REG_TR_REQ_IOVA 0x0258
+
+/* 5.25 Translation request control (64bits) */
+#define RISCV_IOMMU_REG_TR_REQ_CTL 0x0260
+#define RISCV_IOMMU_TR_REQ_CTL_GO_BUSY BIT_ULL(0)
+#define RISCV_IOMMU_TR_REQ_CTL_NW BIT_ULL(3)
+#define RISCV_IOMMU_TR_REQ_CTL_PID GENMASK_ULL(31, 12)
+#define RISCV_IOMMU_TR_REQ_CTL_DID GENMASK_ULL(63, 40)
+
+/* 5.26 Translation request response (64bits) */
+#define RISCV_IOMMU_REG_TR_RESPONSE 0x0268
+#define RISCV_IOMMU_TR_RESPONSE_FAULT BIT_ULL(0)
+#define RISCV_IOMMU_TR_RESPONSE_S BIT_ULL(9)
+#define RISCV_IOMMU_TR_RESPONSE_PPN RISCV_IOMMU_PPN_FIELD
+
/* 5.27 Interrupt cause to vector (64bits) */
#define RISCV_IOMMU_REG_ICVEC 0x02F8
#define RISCV_IOMMU_ICVEC_CIV GENMASK_ULL(3, 0)
diff --git a/hw/riscv/riscv-iommu.c b/hw/riscv/riscv-iommu.c
index 1a8da005c0..feb650549a 100644
--- a/hw/riscv/riscv-iommu.c
+++ b/hw/riscv/riscv-iommu.c
@@ -1764,6 +1764,50 @@ static void riscv_iommu_process_pq_control(RISCVIOMMUState *s)
riscv_iommu_reg_mod32(s, RISCV_IOMMU_REG_PQCSR, ctrl_set, ctrl_clr);
}
+static void riscv_iommu_process_dbg(RISCVIOMMUState *s)
+{
+ uint64_t iova = riscv_iommu_reg_get64(s, RISCV_IOMMU_REG_TR_REQ_IOVA);
+ uint64_t ctrl = riscv_iommu_reg_get64(s, RISCV_IOMMU_REG_TR_REQ_CTL);
+ unsigned devid = get_field(ctrl, RISCV_IOMMU_TR_REQ_CTL_DID);
+ unsigned pid = get_field(ctrl, RISCV_IOMMU_TR_REQ_CTL_PID);
+ RISCVIOMMUContext *ctx;
+ void *ref;
+
+ if (!(ctrl & RISCV_IOMMU_TR_REQ_CTL_GO_BUSY)) {
+ return;
+ }
+
+ ctx = riscv_iommu_ctx(s, devid, pid, &ref);
+ if (ctx == NULL) {
+ riscv_iommu_reg_set64(s, RISCV_IOMMU_REG_TR_RESPONSE,
+ RISCV_IOMMU_TR_RESPONSE_FAULT |
+ (RISCV_IOMMU_FQ_CAUSE_DMA_DISABLED << 10));
+ } else {
+ IOMMUTLBEntry iotlb = {
+ .iova = iova,
+ .perm = ctrl & RISCV_IOMMU_TR_REQ_CTL_NW ? IOMMU_RO : IOMMU_RW,
+ .addr_mask = ~0,
+ .target_as = NULL,
+ };
+ int fault = riscv_iommu_translate(s, ctx, &iotlb, false);
+ if (fault) {
+ iova = RISCV_IOMMU_TR_RESPONSE_FAULT | (((uint64_t) fault) << 10);
+ } else {
+ iova = iotlb.translated_addr & ~iotlb.addr_mask;
+ iova >>= TARGET_PAGE_BITS;
+ iova &= RISCV_IOMMU_TR_RESPONSE_PPN;
+
+ /* We do not support superpages (> 4kbs) for now */
+ iova &= ~RISCV_IOMMU_TR_RESPONSE_S;
+ }
+ riscv_iommu_reg_set64(s, RISCV_IOMMU_REG_TR_RESPONSE, iova);
+ }
+
+ riscv_iommu_reg_mod64(s, RISCV_IOMMU_REG_TR_REQ_CTL, 0,
+ RISCV_IOMMU_TR_REQ_CTL_GO_BUSY);
+ riscv_iommu_ctx_put(s, ref);
+}
+
typedef void riscv_iommu_process_fn(RISCVIOMMUState *s);
static void riscv_iommu_update_icvec(RISCVIOMMUState *s, uint64_t data)
@@ -1928,6 +1972,12 @@ static MemTxResult riscv_iommu_mmio_write(void *opaque, hwaddr addr,
return MEMTX_OK;
+ case RISCV_IOMMU_REG_TR_REQ_CTL:
+ process_fn = riscv_iommu_process_dbg;
+ regb = RISCV_IOMMU_REG_TR_REQ_CTL;
+ busy = RISCV_IOMMU_TR_REQ_CTL_GO_BUSY;
+ break;
+
default:
break;
}
@@ -2065,6 +2115,9 @@ static void riscv_iommu_realize(DeviceState *dev, Error **errp)
s->cap |= RISCV_IOMMU_CAP_SV32X4 | RISCV_IOMMU_CAP_SV39X4 |
RISCV_IOMMU_CAP_SV48X4 | RISCV_IOMMU_CAP_SV57X4;
}
+ /* Enable translation debug interface */
+ s->cap |= RISCV_IOMMU_CAP_DBG;
+
/* Report QEMU target physical address space limits */
s->cap = set_field(s->cap, RISCV_IOMMU_CAP_PAS,
TARGET_PHYS_ADDR_SPACE_BITS);
@@ -2121,6 +2174,12 @@ static void riscv_iommu_realize(DeviceState *dev, Error **errp)
stl_le_p(&s->regs_wc[RISCV_IOMMU_REG_IPSR], ~0);
stl_le_p(&s->regs_ro[RISCV_IOMMU_REG_ICVEC], 0);
stq_le_p(&s->regs_rw[RISCV_IOMMU_REG_DDTP], s->ddtp);
+ /* If debug registers enabled. */
+ if (s->cap & RISCV_IOMMU_CAP_DBG) {
+ stq_le_p(&s->regs_ro[RISCV_IOMMU_REG_TR_REQ_IOVA], 0);
+ stq_le_p(&s->regs_ro[RISCV_IOMMU_REG_TR_REQ_CTL],
+ RISCV_IOMMU_TR_REQ_CTL_GO_BUSY);
+ }
/* Memory region for downstream access, if specified. */
if (s->target_mr) {
--
2.47.0