[PATCH 19/20] habanalabs/gaudi2: change memory scrub mechanism

From: Oded Gabbay
Date: Thu Nov 17 2022 - 11:21:46 EST


From: farah kassabri <fkassabri@xxxxxxxxx>

Currently the scrubbing mechanism used the EDMA engines by directly
setting the engine core registers to scrub a chunk of memory.
Due to a sporadic failure with this mechanism, it was decided to
initiate the engines via its QMAN using LIN-DMA packets.

Signed-off-by: farah kassabri <fkassabri@xxxxxxxxx>
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
---
drivers/misc/habanalabs/gaudi2/gaudi2.c | 129 +++++++++++++++---------
1 file changed, 83 insertions(+), 46 deletions(-)

diff --git a/drivers/misc/habanalabs/gaudi2/gaudi2.c b/drivers/misc/habanalabs/gaudi2/gaudi2.c
index f0f2f77f56de..c14e63164a84 100644
--- a/drivers/misc/habanalabs/gaudi2/gaudi2.c
+++ b/drivers/misc/habanalabs/gaudi2/gaudi2.c
@@ -9171,34 +9171,74 @@ static void gaudi2_handle_eqe(struct hl_device *hdev, struct hl_eq_entry *eq_ent
hl_device_cond_reset(hdev, reset_flags, event_mask);
}

+static int gaudi2_memset_memory_chunk_using_edma_qm(struct hl_device *hdev,
+ struct packet_lin_dma *lin_dma_pkt, dma_addr_t pkt_dma_addr,
+ u32 hw_queue_id, u32 size, u64 addr, u32 val)
+{
+ u32 ctl, pkt_size;
+ int rc = 0;
+
+ ctl = FIELD_PREP(GAUDI2_PKT_CTL_OPCODE_MASK, PACKET_LIN_DMA);
+ ctl |= FIELD_PREP(GAUDI2_PKT_LIN_DMA_CTL_MEMSET_MASK, 1);
+ ctl |= FIELD_PREP(GAUDI2_PKT_LIN_DMA_CTL_WRCOMP_MASK, 1);
+ ctl |= FIELD_PREP(GAUDI2_PKT_CTL_EB_MASK, 1);
+
+ lin_dma_pkt->ctl = cpu_to_le32(ctl);
+ lin_dma_pkt->src_addr = cpu_to_le64(val);
+ lin_dma_pkt->dst_addr = cpu_to_le64(addr);
+ lin_dma_pkt->tsize = cpu_to_le32(size);
+
+ pkt_size = sizeof(struct packet_lin_dma);
+
+ rc = hl_hw_queue_send_cb_no_cmpl(hdev, hw_queue_id, pkt_size, pkt_dma_addr);
+ if (rc)
+ dev_err(hdev->dev, "Failed to send lin dma packet to H/W queue %d\n",
+ hw_queue_id);
+
+ return rc;
+}
+
static int gaudi2_memset_device_memory(struct hl_device *hdev, u64 addr, u64 size, u64 val)
{
- struct asic_fixed_properties *prop = &hdev->asic_prop;
+ u32 edma_queues_id[] = {GAUDI2_QUEUE_ID_DCORE0_EDMA_0_0,
+ GAUDI2_QUEUE_ID_DCORE1_EDMA_0_0,
+ GAUDI2_QUEUE_ID_DCORE2_EDMA_0_0,
+ GAUDI2_QUEUE_ID_DCORE3_EDMA_0_0};
+ u32 chunk_size, dcore, edma_idx, sob_offset, sob_addr, comp_val,
+ old_mmubp, mmubp, num_of_pkts, busy, pkt_size;
u64 comp_addr, cur_addr = addr, end_addr = addr + size;
- u32 chunk_size, busy, dcore, edma_idx, sob_offset, sob_addr, comp_val, edma_commit;
- u32 old_mmubp, mmubp;
- int rc = 0;
+ struct asic_fixed_properties *prop = &hdev->asic_prop;
+ void *lin_dma_pkts_arr;
+ dma_addr_t pkt_dma_addr;
+ int rc = 0, dma_num = 0;
+
+ if (prop->edma_enabled_mask == 0) {
+ dev_info(hdev->dev, "non of the EDMA engines is enabled - skip dram scrubbing\n");
+ return -EIO;
+ }

sob_offset = hdev->asic_prop.first_available_user_sob[0] * 4;
sob_addr = mmDCORE0_SYNC_MNGR_OBJS_SOB_OBJ_0 + sob_offset;
comp_addr = CFG_BASE + sob_addr;
comp_val = FIELD_PREP(DCORE0_SYNC_MNGR_OBJS_SOB_OBJ_INC_MASK, 1) |
FIELD_PREP(DCORE0_SYNC_MNGR_OBJS_SOB_OBJ_VAL_MASK, 1);
-
- edma_commit = FIELD_PREP(ARC_FARM_KDMA_CTX_COMMIT_LIN_MASK, 1) |
- FIELD_PREP(ARC_FARM_KDMA_CTX_COMMIT_MEM_SET_MASK, 1) |
- FIELD_PREP(ARC_FARM_KDMA_CTX_COMMIT_WR_COMP_EN_MASK, 1);
mmubp = FIELD_PREP(ARC_FARM_KDMA_CTX_AXUSER_HB_MMU_BP_WR_MASK, 1) |
FIELD_PREP(ARC_FARM_KDMA_CTX_AXUSER_HB_MMU_BP_RD_MASK, 1);

- if (prop->edma_enabled_mask == 0) {
- dev_info(hdev->dev, "non of the EDMA engines is enabled - skip dram scrubbing\n");
- return -EIO;
- }
+ /* Calculate how many lin dma pkts we'll need */
+ num_of_pkts = div64_u64(round_up(size, SZ_2G), SZ_2G);
+ pkt_size = sizeof(struct packet_lin_dma);
+
+ lin_dma_pkts_arr = hl_asic_dma_alloc_coherent(hdev, pkt_size * num_of_pkts,
+ &pkt_dma_addr, GFP_KERNEL);
+ if (!lin_dma_pkts_arr)
+ return -ENOMEM;

/*
* set mmu bypass for the scrubbing - all ddmas are configured the same so save
* only the first one to restore later
+ * also set the sob addr for all edma cores for completion.
+ * set QM as trusted to allow it to access physical address with MMU bp.
*/
old_mmubp = RREG32(mmDCORE0_EDMA0_CORE_CTX_AXUSER_HB_MMU_BP);
for (dcore = 0 ; dcore < NUM_OF_DCORES ; dcore++) {
@@ -9211,17 +9251,22 @@ static int gaudi2_memset_device_memory(struct hl_device *hdev, u64 addr, u64 siz

WREG32(mmDCORE0_EDMA0_CORE_CTX_AXUSER_HB_MMU_BP +
edma_offset, mmubp);
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_LO + edma_offset,
+ lower_32_bits(comp_addr));
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_HI + edma_offset,
+ upper_32_bits(comp_addr));
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_WDATA + edma_offset,
+ comp_val);
+ gaudi2_qman_set_test_mode(hdev,
+ edma_queues_id[dcore] + 4 * edma_idx, true);
}
}

- while (cur_addr < end_addr) {
- int dma_num = 0;
+ WREG32(sob_addr, 0);

- WREG32(sob_addr, 0);
+ while (cur_addr < end_addr) {
for (dcore = 0 ; dcore < NUM_OF_DCORES ; dcore++) {
for (edma_idx = 0 ; edma_idx < NUM_OF_EDMA_PER_DCORE ; edma_idx++) {
- u32 edma_offset = dcore * DCORE_OFFSET +
- edma_idx * DCORE_EDMA_OFFSET;
u32 edma_bit = dcore * NUM_OF_EDMA_PER_DCORE + edma_idx;

if (!(prop->edma_enabled_mask & BIT(edma_bit)))
@@ -9229,41 +9274,26 @@ static int gaudi2_memset_device_memory(struct hl_device *hdev, u64 addr, u64 siz

chunk_size = min_t(u64, SZ_2G, end_addr - cur_addr);

- WREG32(mmDCORE0_EDMA0_CORE_CTX_SRC_BASE_LO + edma_offset,
- lower_32_bits(val));
- WREG32(mmDCORE0_EDMA0_CORE_CTX_SRC_BASE_HI + edma_offset,
- upper_32_bits(val));
-
- WREG32(mmDCORE0_EDMA0_CORE_CTX_DST_BASE_LO + edma_offset,
- lower_32_bits(cur_addr));
- WREG32(mmDCORE0_EDMA0_CORE_CTX_DST_BASE_HI + edma_offset,
- upper_32_bits(cur_addr));
-
- WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_LO + edma_offset,
- lower_32_bits(comp_addr));
- WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_HI + edma_offset,
- upper_32_bits(comp_addr));
- WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_WDATA + edma_offset,
- comp_val);
-
- WREG32(mmDCORE0_EDMA0_CORE_CTX_DST_TSIZE_0 + edma_offset,
- chunk_size);
- WREG32(mmDCORE0_EDMA0_CORE_CTX_COMMIT + edma_offset, edma_commit);
+ rc = gaudi2_memset_memory_chunk_using_edma_qm(hdev,
+ (struct packet_lin_dma *)lin_dma_pkts_arr + dma_num,
+ pkt_dma_addr + dma_num * pkt_size,
+ edma_queues_id[dcore] + edma_idx * 4,
+ chunk_size, cur_addr, val);
+ if (rc)
+ goto end;

dma_num++;
-
cur_addr += chunk_size;
-
if (cur_addr == end_addr)
- goto poll;
+ break;
}
}
-poll:
- rc = hl_poll_timeout(hdev, sob_addr, busy, (busy == dma_num), 1000, 1000000);
- if (rc) {
- dev_err(hdev->dev, "DMA Timeout during HBM scrubbing\n");
- goto end;
- }
+ }
+
+ rc = hl_poll_timeout(hdev, sob_addr, busy, (busy == dma_num), 1000, 1000000);
+ if (rc) {
+ dev_err(hdev->dev, "DMA Timeout during HBM scrubbing\n");
+ goto end;
}
end:
for (dcore = 0 ; dcore < NUM_OF_DCORES ; dcore++) {
@@ -9275,10 +9305,17 @@ static int gaudi2_memset_device_memory(struct hl_device *hdev, u64 addr, u64 siz
continue;

WREG32(mmDCORE0_EDMA0_CORE_CTX_AXUSER_HB_MMU_BP + edma_offset, old_mmubp);
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_LO + edma_offset, 0);
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_ADDR_HI + edma_offset, 0);
+ WREG32(mmDCORE0_EDMA0_CORE_CTX_WR_COMP_WDATA + edma_offset, 0);
+ gaudi2_qman_set_test_mode(hdev,
+ edma_queues_id[dcore] + 4 * edma_idx, false);
}
}

WREG32(sob_addr, 0);
+ hl_asic_dma_free_coherent(hdev, pkt_size * num_of_pkts, lin_dma_pkts_arr, pkt_dma_addr);
+
return rc;
}

--
2.25.1