[PATCH 1/4] habanalabs: improve communication protocol with cpucp

Oded Gabbay
2021-02-02T17:11:59Z

From: Ofir Bitton <obitton@habana.ai>

Current messaging communictaion protocol with cpucp can get out
of sync due to coherency issues. In order to improve the protocol
reliability, we modify the protocol to expect a different
acknowledgment for every packet sent to cpucp.

Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
---
drivers/misc/habanalabs/common/firmware_if.c | 17 +++++++++++++++--
drivers/misc/habanalabs/common/habanalabs.h | 3 +++
drivers/misc/habanalabs/gaudi/gaudi.c | 6 +++++-
drivers/misc/habanalabs/goya/goya.c | 6 +++++-
.../misc/habanalabs/include/common/hl_boot_if.h | 5 +++++
5 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/habanalabs/common/firmware_if.c b/drivers/misc/habanalabs/common/firmware_if.c
index ba6920f2b4ab..31b52a223f02 100644
--- a/drivers/misc/habanalabs/common/firmware_if.c
+++ b/drivers/misc/habanalabs/common/firmware_if.c
@@ -90,9 +90,10 @@ int hl_fw_send_pci_access_msg(struct hl_device *hdev, u32 opcode)
int hl_fw_send_cpu_message(struct hl_device *hdev, u32 hw_queue_id, u32 *msg,
u16 len, u32 timeout, u64 *result)
{
+ struct hl_hw_queue *queue = &hdev->kernel_queues[hw_queue_id];
struct cpucp_packet *pkt;
dma_addr_t pkt_dma_addr;
- u32 tmp;
+ u32 tmp, expected_ack_val;
int rc = 0;

pkt = hdev->asic_funcs->cpu_accessible_dma_pool_alloc(hdev, len,
@@ -115,14 +116,22 @@ int hl_fw_send_cpu_message(struct hl_device *hdev, u32 hw_queue_id, u32 *msg,
goto out;
}

+ /* set fence to a non valid value */
+ pkt->fence = UINT_MAX;
+
rc = hl_hw_queue_send_cb_no_cmpl(hdev, hw_queue_id, len, pkt_dma_addr);
if (rc) {
dev_err(hdev->dev, "Failed to send CB on CPU PQ (%d)\n", rc);
goto out;
}

+ if (hdev->asic_prop.fw_cpucp_ack_with_pi)
+ expected_ack_val = queue->pi;
+ else
+ expected_ack_val = CPUCP_PACKET_FENCE_VAL;
+
rc = hl_poll_timeout_memory(hdev, &pkt->fence, tmp,
- (tmp == CPUCP_PACKET_FENCE_VAL), 1000,
+ (tmp == expected_ack_val), 1000,
timeout, true);

hl_hw_queue_inc_ci_kernel(hdev, hw_queue_id);
@@ -777,6 +786,10 @@ int hl_fw_init_cpu(struct hl_device *hdev, u32 cpu_boot_status_reg,
CPU_BOOT_DEV_STS0_FW_HARD_RST_EN)
prop->hard_reset_done_by_fw = true;

+ if (prop->fw_boot_cpu_security_map &
+ CPU_BOOT_DEV_STS0_PKT_PI_ACK_EN)
+ prop->fw_cpucp_ack_with_pi = true;
+
dev_dbg(hdev->dev,
"Firmware boot CPU security status %#x\n",
prop->fw_boot_cpu_security_map);
diff --git a/drivers/misc/habanalabs/common/habanalabs.h b/drivers/misc/habanalabs/common/habanalabs.h
index 30f32f2edb8a..3c54010f7ab9 100644
--- a/drivers/misc/habanalabs/common/habanalabs.h
+++ b/drivers/misc/habanalabs/common/habanalabs.h
@@ -419,6 +419,8 @@ struct hl_mmu_properties {
* from BOOT_DEV_STS0
* @dram_supports_virtual_memory: is there an MMU towards the DRAM
* @hard_reset_done_by_fw: true if firmware is handling hard reset flow
+ * @fw_cpucp_ack_with_pi: true if cpucp is acking messages with the PQ PI
+ * instead of a magic number
* @num_functional_hbms: number of functional HBMs in each DCORE.
*/
struct asic_fixed_properties {
@@ -479,6 +481,7 @@ struct asic_fixed_properties {
u8 fw_security_status_valid;
u8 dram_supports_virtual_memory;
u8 hard_reset_done_by_fw;
+ u8 fw_cpucp_ack_with_pi;
u8 num_functional_hbms;
};

diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c b/drivers/misc/habanalabs/gaudi/gaudi.c
index 52fcaf25531a..006c34ae35c2 100644
--- a/drivers/misc/habanalabs/gaudi/gaudi.c
+++ b/drivers/misc/habanalabs/gaudi/gaudi.c
@@ -533,6 +533,7 @@ static int gaudi_get_fixed_properties(struct hl_device *hdev)
prop->fw_security_disabled = true;
prop->fw_security_status_valid = false;
prop->hard_reset_done_by_fw = false;
+ prop->fw_cpucp_ack_with_pi = false;

return 0;
}
@@ -4438,9 +4439,12 @@ static void gaudi_ring_doorbell(struct hl_device *hdev, u32 hw_queue_id, u32 pi)
/* ring the doorbell */
WREG32(db_reg_offset, db_value);

- if (hw_queue_id == GAUDI_QUEUE_ID_CPU_PQ)
+ if (hw_queue_id == GAUDI_QUEUE_ID_CPU_PQ) {
+ /* make sure device CPU will read latest data from host */
+ mb();
WREG32(mmGIC_DISTRIBUTOR__5_GICD_SETSPI_NSR,
GAUDI_EVENT_PI_UPDATE);
+ }
}

static void gaudi_pqe_write(struct hl_device *hdev, __le64 *pqe,
diff --git a/drivers/misc/habanalabs/goya/goya.c b/drivers/misc/habanalabs/goya/goya.c
index a954e7c02375..53db7e966866 100644
--- a/drivers/misc/habanalabs/goya/goya.c
+++ b/drivers/misc/habanalabs/goya/goya.c
@@ -461,6 +461,7 @@ int goya_get_fixed_properties(struct hl_device *hdev)
prop->fw_security_disabled = true;
prop->fw_security_status_valid = false;
prop->hard_reset_done_by_fw = false;
+ prop->fw_cpucp_ack_with_pi = false;

return 0;
}
@@ -2806,9 +2807,12 @@ void goya_ring_doorbell(struct hl_device *hdev, u32 hw_queue_id, u32 pi)
/* ring the doorbell */
WREG32(db_reg_offset, db_value);

- if (hw_queue_id == GOYA_QUEUE_ID_CPU_PQ)
+ if (hw_queue_id == GOYA_QUEUE_ID_CPU_PQ) {
+ /* make sure device CPU will read latest data from host */
+ mb();
WREG32(mmGIC_DISTRIBUTOR__5_GICD_SETSPI_NSR,
GOYA_ASYNC_EVENT_ID_PI_UPDATE);
+ }
}

void goya_pqe_write(struct hl_device *hdev, __le64 *pqe, struct hl_bd *bd)
diff --git a/drivers/misc/habanalabs/include/common/hl_boot_if.h b/drivers/misc/habanalabs/include/common/hl_boot_if.h
index 57785478a4ef..e87f5a98e193 100644
--- a/drivers/misc/habanalabs/include/common/hl_boot_if.h
+++ b/drivers/misc/habanalabs/include/common/hl_boot_if.h
@@ -166,6 +166,10 @@
* FW handles HBM ECC indications.
* Initialized in: linux
*
+ * CPU_BOOT_DEV_STS0_PKT_PI_ACK_EN Packets ack value used in the armcpd
+ * is set to the PI counter.
+ * Initialized in: linux
+ *
* CPU_BOOT_DEV_STS0_ENABLED Device status register enabled.
* This is a main indication that the
* running FW populates the device status
@@ -190,6 +194,7 @@
#define CPU_BOOT_DEV_STS0_SP_SRAM_EN (1 << 12)
#define CPU_BOOT_DEV_STS0_CLK_GATE_EN (1 << 13)
#define CPU_BOOT_DEV_STS0_HBM_ECC_EN (1 << 14)
+#define CPU_BOOT_DEV_STS0_PKT_PI_ACK_EN (1 << 15)
#define CPU_BOOT_DEV_STS0_ENABLED (1 << 31)

enum cpu_boot_status {
--
2.25.1