[PATCH 5/7] habanalabs/gaudi: skip iATU if F/W security is enabled

From: Oded Gabbay
Date: Thu Apr 08 2021 - 11:22:58 EST


From: Ofir Bitton <obitton@xxxxxxxxx>

As part of the securing GAUDI, the F/W will configure the PCI iATU
regions. If the driver identifies a secured PCI ID, it will know to
skip iATU configuration in a very early stage.

Signed-off-by: Ofir Bitton <obitton@xxxxxxxxx>
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
---
drivers/misc/habanalabs/common/habanalabs.h | 3 ++
drivers/misc/habanalabs/common/pci/pci.c | 52 +++++++++++++++++++++
drivers/misc/habanalabs/gaudi/gaudi.c | 23 +++++++++
drivers/misc/habanalabs/goya/goya.c | 24 +++++++++-
4 files changed, 101 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/habanalabs/common/habanalabs.h b/drivers/misc/habanalabs/common/habanalabs.h
index c1b46126c522..44e89da30b4a 100644
--- a/drivers/misc/habanalabs/common/habanalabs.h
+++ b/drivers/misc/habanalabs/common/habanalabs.h
@@ -445,6 +445,7 @@ struct hl_mmu_properties {
* @dram_supports_virtual_memory: is there an MMU towards the DRAM
* @hard_reset_done_by_fw: true if firmware is handling hard reset flow
* @num_functional_hbms: number of functional HBMs in each DCORE.
+ * @iatu_done_by_fw: true if iATU configuration is being done by FW.
*/
struct asic_fixed_properties {
struct hw_queue_properties *hw_queues_props;
@@ -508,6 +509,7 @@ struct asic_fixed_properties {
u8 dram_supports_virtual_memory;
u8 hard_reset_done_by_fw;
u8 num_functional_hbms;
+ u8 iatu_done_by_fw;
};

/**
@@ -2400,6 +2402,7 @@ int hl_fw_read_preboot_status(struct hl_device *hdev, u32 cpu_boot_status_reg,

int hl_pci_bars_map(struct hl_device *hdev, const char * const name[3],
bool is_wc[3]);
+int hl_pci_elbi_read(struct hl_device *hdev, u64 addr, u32 *data);
int hl_pci_iatu_write(struct hl_device *hdev, u32 addr, u32 data);
int hl_pci_set_inbound_region(struct hl_device *hdev, u8 region,
struct hl_inbound_pci_region *pci_region);
diff --git a/drivers/misc/habanalabs/common/pci/pci.c b/drivers/misc/habanalabs/common/pci/pci.c
index b799f9258fb0..e941b7eef346 100644
--- a/drivers/misc/habanalabs/common/pci/pci.c
+++ b/drivers/misc/habanalabs/common/pci/pci.c
@@ -85,6 +85,58 @@ static void hl_pci_bars_unmap(struct hl_device *hdev)
pci_release_regions(pdev);
}

+int hl_pci_elbi_read(struct hl_device *hdev, u64 addr, u32 *data)
+{
+ struct pci_dev *pdev = hdev->pdev;
+ ktime_t timeout;
+ u64 msec;
+ u32 val;
+
+ if (hdev->pldm)
+ msec = HL_PLDM_PCI_ELBI_TIMEOUT_MSEC;
+ else
+ msec = HL_PCI_ELBI_TIMEOUT_MSEC;
+
+ /* Clear previous status */
+ pci_write_config_dword(pdev, mmPCI_CONFIG_ELBI_STS, 0);
+
+ pci_write_config_dword(pdev, mmPCI_CONFIG_ELBI_ADDR, (u32) addr);
+ pci_write_config_dword(pdev, mmPCI_CONFIG_ELBI_CTRL, 0);
+
+ timeout = ktime_add_ms(ktime_get(), msec);
+ for (;;) {
+ pci_read_config_dword(pdev, mmPCI_CONFIG_ELBI_STS, &val);
+ if (val & PCI_CONFIG_ELBI_STS_MASK)
+ break;
+ if (ktime_compare(ktime_get(), timeout) > 0) {
+ pci_read_config_dword(pdev, mmPCI_CONFIG_ELBI_STS,
+ &val);
+ break;
+ }
+
+ usleep_range(300, 500);
+ }
+
+ if ((val & PCI_CONFIG_ELBI_STS_MASK) == PCI_CONFIG_ELBI_STS_DONE) {
+ pci_read_config_dword(pdev, mmPCI_CONFIG_ELBI_DATA, data);
+
+ return 0;
+ }
+
+ if (val & PCI_CONFIG_ELBI_STS_ERR) {
+ dev_err(hdev->dev, "Error reading from ELBI\n");
+ return -EIO;
+ }
+
+ if (!(val & PCI_CONFIG_ELBI_STS_MASK)) {
+ dev_err(hdev->dev, "ELBI read didn't finish in time\n");
+ return -EIO;
+ }
+
+ dev_err(hdev->dev, "ELBI read has undefined bits in status\n");
+ return -EIO;
+}
+
/**
* hl_pci_elbi_write() - Write through the ELBI interface.
* @hdev: Pointer to hl_device structure.
diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c b/drivers/misc/habanalabs/gaudi/gaudi.c
index 841748392e49..8730b691ec61 100644
--- a/drivers/misc/habanalabs/gaudi/gaudi.c
+++ b/drivers/misc/habanalabs/gaudi/gaudi.c
@@ -629,6 +629,11 @@ static int gaudi_init_iatu(struct hl_device *hdev)
struct hl_outbound_pci_region outbound_region;
int rc;

+ if (hdev->asic_prop.iatu_done_by_fw) {
+ hdev->asic_funcs->set_dma_mask_from_fw(hdev);
+ return 0;
+ }
+
/* Inbound Region 0 - Bar 0 - Point to SRAM + CFG */
inbound_region.mode = PCI_BAR_MATCH_MODE;
inbound_region.bar = SRAM_BAR_ID;
@@ -673,6 +678,7 @@ static int gaudi_early_init(struct hl_device *hdev)
{
struct asic_fixed_properties *prop = &hdev->asic_prop;
struct pci_dev *pdev = hdev->pdev;
+ u32 fw_boot_status;
int rc;

rc = gaudi_get_fixed_properties(hdev);
@@ -706,6 +712,23 @@ static int gaudi_early_init(struct hl_device *hdev)

prop->dram_pci_bar_size = pci_resource_len(pdev, HBM_BAR_ID);

+ /* If FW security is enabled at this point it means no access to ELBI */
+ if (!hdev->asic_prop.fw_security_disabled) {
+ hdev->asic_prop.iatu_done_by_fw = true;
+ goto pci_init;
+ }
+
+ rc = hl_pci_elbi_read(hdev, CFG_BASE + mmCPU_BOOT_DEV_STS0,
+ &fw_boot_status);
+ if (rc)
+ goto free_queue_props;
+
+ /* Check whether FW is configuring iATU */
+ if ((fw_boot_status & CPU_BOOT_DEV_STS0_ENABLED) &&
+ (fw_boot_status & CPU_BOOT_DEV_STS0_FW_IATU_CONF_EN))
+ hdev->asic_prop.iatu_done_by_fw = true;
+
+pci_init:
rc = hl_pci_init(hdev);
if (rc)
goto free_queue_props;
diff --git a/drivers/misc/habanalabs/goya/goya.c b/drivers/misc/habanalabs/goya/goya.c
index 44dd4d8d8822..e27338f4aad2 100644
--- a/drivers/misc/habanalabs/goya/goya.c
+++ b/drivers/misc/habanalabs/goya/goya.c
@@ -555,6 +555,11 @@ static int goya_init_iatu(struct hl_device *hdev)
struct hl_outbound_pci_region outbound_region;
int rc;

+ if (hdev->asic_prop.iatu_done_by_fw) {
+ hdev->asic_funcs->set_dma_mask_from_fw(hdev);
+ return 0;
+ }
+
/* Inbound Region 0 - Bar 0 - Point to SRAM and CFG */
inbound_region.mode = PCI_BAR_MATCH_MODE;
inbound_region.bar = SRAM_CFG_BAR_ID;
@@ -602,7 +607,7 @@ static int goya_early_init(struct hl_device *hdev)
{
struct asic_fixed_properties *prop = &hdev->asic_prop;
struct pci_dev *pdev = hdev->pdev;
- u32 val;
+ u32 fw_boot_status, val;
int rc;

rc = goya_get_fixed_properties(hdev);
@@ -636,6 +641,23 @@ static int goya_early_init(struct hl_device *hdev)

prop->dram_pci_bar_size = pci_resource_len(pdev, DDR_BAR_ID);

+ /* If FW security is enabled at this point it means no access to ELBI */
+ if (!hdev->asic_prop.fw_security_disabled) {
+ hdev->asic_prop.iatu_done_by_fw = true;
+ goto pci_init;
+ }
+
+ rc = hl_pci_elbi_read(hdev, CFG_BASE + mmCPU_BOOT_DEV_STS0,
+ &fw_boot_status);
+ if (rc)
+ goto free_queue_props;
+
+ /* Check whether FW is configuring iATU */
+ if ((fw_boot_status & CPU_BOOT_DEV_STS0_ENABLED) &&
+ (fw_boot_status & CPU_BOOT_DEV_STS0_FW_IATU_CONF_EN))
+ hdev->asic_prop.iatu_done_by_fw = true;
+
+pci_init:
rc = hl_pci_init(hdev);
if (rc)
goto free_queue_props;
--
2.25.1