diff options
Diffstat (limited to 'drivers/misc/habanalabs/common/pci/pci.c')
| -rw-r--r-- | drivers/misc/habanalabs/common/pci/pci.c | 52 |
1 files changed, 52 insertions, 0 deletions
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. |