This patch enables support in the driver for 64-bit DMA mask when running
in a POWER9 machine.
POWER9 supports either 32-bit or 64-bit DMA mask. However, our ASICs
support 48-bit DMA mask. To support 64-bit, the driver needs to add a
special configuration to the ASIC's PCIe controller.
The activation of this special configuration is done in case the PCI
parent device of Goya is a PHB4 PCI device of IBM.
Signed-off-by: Oded Gabbay <oded.gab...@gmail.com>
---
Changes in v2:
- Remove kernel module parameter and instead read the PCI device ID of the
parent PCI bus. If it is PHB4, do the special configuration.
drivers/misc/habanalabs/goya/goya.c | 6 +++++-
drivers/misc/habanalabs/habanalabs.h | 4 ++++
drivers/misc/habanalabs/pci.c | 23 ++++++++++++++++++++++-
3 files changed, 31 insertions(+), 2 deletions(-)
diff --git a/drivers/misc/habanalabs/goya/goya.c
b/drivers/misc/habanalabs/goya/goya.c
index e8b3a31d211f..71dc2341dd8c 100644
--- a/drivers/misc/habanalabs/goya/goya.c
+++ b/drivers/misc/habanalabs/goya/goya.c
@@ -472,7 +472,11 @@ static int goya_early_init(struct hl_device *hdev)
prop->dram_pci_bar_size = pci_resource_len(pdev, DDR_BAR_ID);
- rc = hl_pci_init(hdev, 48);
+ if (hl_pci_parent_is_phb4(hdev))
+ rc = hl_pci_init(hdev, 64);
+ else
+ rc = hl_pci_init(hdev, 48);
+
if (rc)
return rc;
diff --git a/drivers/misc/habanalabs/habanalabs.h
b/drivers/misc/habanalabs/habanalabs.h
index 5e4a631b3d88..3ba94188884f 100644
--- a/drivers/misc/habanalabs/habanalabs.h
+++ b/drivers/misc/habanalabs/habanalabs.h
@@ -1208,6 +1208,8 @@ struct hl_device_reset_work {
* @dma_mask: the dma mask that was set for this device
* @in_debug: is device under debug. This, together with fd_open_cnt, enforces
* that only a single user is configuring the debug infrastructure.
+ * @power9_64bit_dma_enable: true to enable 64-bit DMA mask support. Relevant
+ * only to POWER9 machines.
*/
struct hl_device {
struct pci_dev *pdev;
@@ -1281,6 +1283,7 @@ struct hl_device {
u8 device_cpu_disabled;
u8 dma_mask;
u8 in_debug;
+ u8 power9_64bit_dma_enable;
/* Parameters for bring-up */
u8 mmu_enable;
@@ -1504,6 +1507,7 @@ int hl_pci_init_iatu(struct hl_device *hdev, u64
sram_base_address,
int hl_pci_init(struct hl_device *hdev, u8 dma_mask);
void hl_pci_fini(struct hl_device *hdev);
int hl_pci_set_dma_mask(struct hl_device *hdev, u8 dma_mask);
+bool hl_pci_parent_is_phb4(struct hl_device *hdev);
long hl_get_frequency(struct hl_device *hdev, u32 pll_index, bool curr);
void hl_set_frequency(struct hl_device *hdev, u32 pll_index, u64 freq);
diff --git a/drivers/misc/habanalabs/pci.c b/drivers/misc/habanalabs/pci.c
index c98d88c7a5c6..dcb737f9677c 100644
--- a/drivers/misc/habanalabs/pci.c
+++ b/drivers/misc/habanalabs/pci.c
@@ -10,6 +10,8 @@
#include <linux/pci.h>
+#define PCI_DEVICE_ID_IBM_PHB4 0x04C1
+
#define HL_PLDM_PCI_ELBI_TIMEOUT_MSEC (HL_PCI_ELBI_TIMEOUT_MSEC * 10)
/**
@@ -182,6 +184,20 @@ static void hl_pci_reset_link_through_bridge(struct
hl_device *hdev)
ssleep(3);
}
+bool hl_pci_parent_is_phb4(struct hl_device *hdev)
+{
+ struct pci_dev *parent_port = hdev->pdev->bus->self;
+
+ if ((parent_port->vendor == PCI_VENDOR_ID_IBM) &&
+ (parent_port->device == PCI_DEVICE_ID_IBM_PHB4)) {
+ hdev->power9_64bit_dma_enable = 1;
+ return true;
+ }
+
+ hdev->power9_64bit_dma_enable = 0;
+ return false;
+}
+
/**
* hl_pci_set_dram_bar_base() - Set DDR BAR to map specific device address.
* @hdev: Pointer to hl_device structure.
@@ -283,7 +299,12 @@ int hl_pci_init_iatu(struct hl_device *hdev, u64
sram_base_address,
upper_32_bits(host_phys_base_address));
rc |= hl_pci_iatu_write(hdev, 0x010, lower_32_bits(host_phys_end_addr));
rc |= hl_pci_iatu_write(hdev, 0x014, 0);
- rc |= hl_pci_iatu_write(hdev, 0x018, 0);
+
+ if ((hdev->power9_64bit_dma_enable) && (hdev->dma_mask == 64))
+ rc |= hl_pci_iatu_write(hdev, 0x018, 0x08000000);
+ else
+ rc |= hl_pci_iatu_write(hdev, 0x018, 0);
+
rc |= hl_pci_iatu_write(hdev, 0x020, upper_32_bits(host_phys_end_addr));
/* Increase region size */
rc |= hl_pci_iatu_write(hdev, 0x000, 0x00002000);
--
2.17.1
