lkml.org 
[lkml]   [2022]   [Jul]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 03/12] habanalabs/gaudi2: configure virtual MSI-X doorbell interface
Date
From: Tomer Tayar <ttayar@habana.ai>

Due to a watchdog timer in the LBW path, writes to the MSI-X doorbell
can return sporadic error responses.
To work-around this issue, a virtual MSI-X doorbell on the HBW path is
configured, using the MSI-X AXI slave interface in the PCIe controller.
Upon an access to a configured HBW host address, the controller will
generate MSI-X interrupt instead of treating the access as regular host
memory access.

This patch allocates the dedicate host memory page, and communicate the
address to F/W, so it will configure the relevant address match
registers in the controller, and will use this address to generate MSI-X
interrupts for F/W events.

Following patches will handle other initiators in the device, to move
them to use the virtual MSI-X doorbell.

Signed-off-by: Tomer Tayar <ttayar@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
---
drivers/misc/habanalabs/gaudi2/gaudi2.c | 23 ++++++++++++++++---
drivers/misc/habanalabs/gaudi2/gaudi2P.h | 5 ++++
drivers/misc/habanalabs/gaudi2/gaudi2_masks.h | 3 +++
3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/habanalabs/gaudi2/gaudi2.c b/drivers/misc/habanalabs/gaudi2/gaudi2.c
index d9a85ea56f75..539cb88a88e4 100644
--- a/drivers/misc/habanalabs/gaudi2/gaudi2.c
+++ b/drivers/misc/habanalabs/gaudi2/gaudi2.c
@@ -2673,9 +2673,11 @@ static void gaudi2_scrub_arcs_dccm(struct hl_device *hdev)

static int gaudi2_late_init(struct hl_device *hdev)
{
+ struct gaudi2_device *gaudi2 = hdev->asic_specific;
int rc;

- rc = hl_fw_send_pci_access_msg(hdev, CPUCP_PACKET_ENABLE_PCI_ACCESS, 0x0);
+ rc = hl_fw_send_pci_access_msg(hdev, CPUCP_PACKET_ENABLE_PCI_ACCESS,
+ gaudi2->virt_msix_db_dma_addr);
if (rc) {
dev_err(hdev->dev, "Failed to enable PCI access from CPU\n");
return rc;
@@ -2922,6 +2924,7 @@ static inline int gaudi2_get_non_zero_random_int(void)

static int gaudi2_sw_init(struct hl_device *hdev)
{
+ struct asic_fixed_properties *prop = &hdev->asic_prop;
struct gaudi2_device *gaudi2;
int i, rc;

@@ -2982,6 +2985,14 @@ static int gaudi2_sw_init(struct hl_device *hdev)
goto free_cpu_accessible_dma_pool;
}

+ gaudi2->virt_msix_db_cpu_addr = hl_cpu_accessible_dma_pool_alloc(hdev, prop->pmmu.page_size,
+ &gaudi2->virt_msix_db_dma_addr);
+ if (!gaudi2->virt_msix_db_cpu_addr) {
+ dev_err(hdev->dev, "Failed to allocate DMA memory for virtual MSI-X doorbell\n");
+ rc = -ENOMEM;
+ goto free_cpu_accessible_dma_pool;
+ }
+
spin_lock_init(&gaudi2->hw_queues_lock);
spin_lock_init(&gaudi2->kdma_lock);

@@ -2990,7 +3001,7 @@ static int gaudi2_sw_init(struct hl_device *hdev)
GFP_KERNEL | __GFP_ZERO);
if (!gaudi2->scratchpad_kernel_address) {
rc = -ENOMEM;
- goto free_cpu_accessible_dma_pool;
+ goto free_virt_msix_db_mem;
}

gaudi2_user_mapped_blocks_init(hdev);
@@ -2999,15 +3010,18 @@ static int gaudi2_sw_init(struct hl_device *hdev)
gaudi2_user_interrupt_setup(hdev);

hdev->supports_coresight = true;
- hdev->asic_prop.supports_soft_reset = true;
hdev->supports_sync_stream = true;
hdev->supports_cb_mapping = true;
hdev->supports_wait_for_multi_cs = false;

+ prop->supports_soft_reset = true;
+
hdev->asic_funcs->set_pci_memory_regions(hdev);

return 0;

+free_virt_msix_db_mem:
+ hl_cpu_accessible_dma_pool_free(hdev, prop->pmmu.page_size, gaudi2->virt_msix_db_cpu_addr);
free_cpu_accessible_dma_pool:
gen_pool_destroy(hdev->cpu_accessible_dma_pool);
free_cpu_dma_mem:
@@ -3022,8 +3036,11 @@ static int gaudi2_sw_init(struct hl_device *hdev)

static int gaudi2_sw_fini(struct hl_device *hdev)
{
+ struct asic_fixed_properties *prop = &hdev->asic_prop;
struct gaudi2_device *gaudi2 = hdev->asic_specific;

+ hl_cpu_accessible_dma_pool_free(hdev, prop->pmmu.page_size, gaudi2->virt_msix_db_cpu_addr);
+
gen_pool_destroy(hdev->cpu_accessible_dma_pool);

hl_asic_dma_free_coherent(hdev, HL_CPU_ACCESSIBLE_MEM_SIZE, hdev->cpu_accessible_dma_mem,
diff --git a/drivers/misc/habanalabs/gaudi2/gaudi2P.h b/drivers/misc/habanalabs/gaudi2/gaudi2P.h
index dc0094a2a911..012413d7df9a 100644
--- a/drivers/misc/habanalabs/gaudi2/gaudi2P.h
+++ b/drivers/misc/habanalabs/gaudi2/gaudi2P.h
@@ -439,6 +439,8 @@ struct dup_block_ctx {
* currently used for HBW QMAN writes which is
* redundant.
* @scratchpad_bus_address: scratchpad bus address
+ * @virt_msix_db_cpu_addr: host memory page for the virtual MSI-X doorbell.
+ * @virt_msix_db_dma_addr: bus address of the page for the virtual MSI-X doorbell.
* @dram_bar_cur_addr: current address of DRAM PCI bar.
* @hw_cap_initialized: This field contains a bit per H/W engine. When that
* engine is initialized, that bit is set by the driver to
@@ -499,6 +501,9 @@ struct gaudi2_device {
void *scratchpad_kernel_address;
dma_addr_t scratchpad_bus_address;

+ void *virt_msix_db_cpu_addr;
+ dma_addr_t virt_msix_db_dma_addr;
+
u64 dram_bar_cur_addr;
u64 hw_cap_initialized;
u64 active_hw_arc;
diff --git a/drivers/misc/habanalabs/gaudi2/gaudi2_masks.h b/drivers/misc/habanalabs/gaudi2/gaudi2_masks.h
index 19ec1f130bef..3fd5cf4a8645 100644
--- a/drivers/misc/habanalabs/gaudi2/gaudi2_masks.h
+++ b/drivers/misc/habanalabs/gaudi2/gaudi2_masks.h
@@ -132,4 +132,7 @@
#define ROT_MSS_HALT_RSB_MASK BIT(1)
#define ROT_MSS_HALT_MRSB_MASK BIT(2)

+#define PCIE_DBI_MSIX_ADDRESS_MATCH_LOW_OFF_MSIX_ADDRESS_MATCH_EN_SHIFT 0
+#define PCIE_DBI_MSIX_ADDRESS_MATCH_LOW_OFF_MSIX_ADDRESS_MATCH_EN_MASK 0x1
+
#endif /* GAUDI2_MASKS_H_ */
--
2.25.1
\
 
 \ /
  Last update: 2022-07-11 08:30    [W:0.052 / U:0.420 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site