diff options
| author | Shanker Donthineni <sdonthineni@nvidia.com> | 2021-08-17 23:34:59 +0530 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2021-08-18 17:32:42 -0500 |
| commit | 6937b7dd434962377e00efc04adac0390c287199 (patch) | |
| tree | 59b281bc05bce2d5fa7407458423c873c453acc9 | |
| parent | 375553a93201a58a52f142eab19545a07aa1eaf5 (diff) | |
PCI: Add support for ACPI _RST reset method
_RST is a standard ACPI method that performs a function level reset of a
device (ACPI v6.3, sec 7.3.25).
Add pci_dev_acpi_reset() to probe for _RST method and execute if present.
The default priority of this reset is set to below device-specific and
above hardware resets.
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-9-ameynarkhede03@gmail.com
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
| -rw-r--r-- | drivers/pci/pci-acpi.c | 23 | ||||
| -rw-r--r-- | drivers/pci/pci.c | 1 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 6 | ||||
| -rw-r--r-- | include/linux/pci.h | 2 |
4 files changed, 31 insertions, 1 deletions
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index c27dbb2294e3..b63db75a3dbf 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -941,6 +941,29 @@ void pci_set_acpi_fwnode(struct pci_dev *dev) acpi_pci_find_companion(&dev->dev)); } +/** + * pci_dev_acpi_reset - do a function level reset using _RST method + * @dev: device to reset + * @probe: check if _RST method is included in the acpi_device context. + */ +int pci_dev_acpi_reset(struct pci_dev *dev, int probe) +{ + acpi_handle handle = ACPI_HANDLE(&dev->dev); + + if (!handle || !acpi_has_method(handle, "_RST")) + return -ENOTTY; + + if (probe) + return 0; + + if (ACPI_FAILURE(acpi_evaluate_object(handle, "_RST", NULL, NULL))) { + pci_warn(dev, "ACPI _RST failed\n"); + return -ENOTTY; + } + + return 0; +} + static bool acpi_pci_power_manageable(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6da5f6d87f6a..4d9828160c48 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5126,6 +5126,7 @@ static void pci_dev_restore(struct pci_dev *dev) static const struct pci_reset_fn_method pci_reset_fn_methods[] = { { }, { pci_dev_specific_reset, .name = "device_specific" }, + { pci_dev_acpi_reset, .name = "acpi" }, { pcie_reset_flr, .name = "flr" }, { pci_af_flr, .name = "af_flr" }, { pci_pm_reset, .name = "pm" }, diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 232047e58b73..87cfd8db8827 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -708,7 +708,13 @@ static inline int pci_aer_raw_clear_status(struct pci_dev *dev) { return -EINVAL int pci_acpi_program_hp_params(struct pci_dev *dev); extern const struct attribute_group pci_dev_acpi_attr_group; void pci_set_acpi_fwnode(struct pci_dev *dev); +int pci_dev_acpi_reset(struct pci_dev *dev, int probe); #else +static inline int pci_dev_acpi_reset(struct pci_dev *dev, int probe) +{ + return -ENOTTY; +} + static inline void pci_set_acpi_fwnode(struct pci_dev *dev) {} static inline int pci_acpi_program_hp_params(struct pci_dev *dev) { diff --git a/include/linux/pci.h b/include/linux/pci.h index d1f4d248617b..98718f46a61c 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -50,7 +50,7 @@ PCI_STATUS_PARITY) /* Number of reset methods used in pci_reset_fn_methods array in pci.c */ -#define PCI_NUM_RESET_METHODS 6 +#define PCI_NUM_RESET_METHODS 7 /* * The PCI interface treats multi-function devices as independent |