return true;
}
+/**
+ * pci_rebar_find_pos - find position of resize ctrl reg for BAR
+ * @pdev: PCI device
+ * @bar: BAR to find
+ *
+ * Helper to find the position of the ctrl register for a BAR.
+ * Returns -ENOTSUPP if resizable BARs are not supported at all.
+ * Returns -ENOENT if no ctrl register for the BAR could be found.
+ */
+static int pci_rebar_find_pos(struct pci_dev *pdev, int bar)
+{
+ unsigned int pos, nbars, i;
+ u32 ctrl;
+
+ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
+ if (!pos)
+ return -ENOTSUPP;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ nbars = (ctrl & PCI_REBAR_CTRL_NBAR_MASK) >>
+ PCI_REBAR_CTRL_NBAR_SHIFT;
+
+ for (i = 0; i < nbars; i++, pos += 8) {
+ int bar_idx;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX;
+ if (bar_idx == bar)
+ return pos;
+ }
+
+ return -ENOENT;
+}
+
+/**
+ * pci_rebar_get_possible_sizes - get possible sizes for BAR
+ * @pdev: PCI device
+ * @bar: BAR to query
+ *
+ * Get the possible sizes of a resizable BAR as bitmask defined in the spec
+ * (bit 0=1MB, bit 19=512GB). Returns 0 if BAR isn't resizable.
+ */
+u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
+{
+ int pos;
+ u32 cap;
+
+ pos = pci_rebar_find_pos(pdev, bar);
+ if (pos < 0)
+ return 0;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
+ return (cap & PCI_REBAR_CAP_SIZES) >> 4;
+}
+
+/**
+ * pci_rebar_get_current_size - get the current size of a BAR
+ * @pdev: PCI device
+ * @bar: BAR to set size to
+ *
+ * Read the size of a BAR from the resizable BAR config.
+ * Returns size if found or negative error code.
+ */
+int pci_rebar_get_current_size(struct pci_dev *pdev, int bar)
+{
+ int pos;
+ u32 ctrl;
+
+ pos = pci_rebar_find_pos(pdev, bar);
+ if (pos < 0)
+ return pos;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ return (ctrl & PCI_REBAR_CTRL_BAR_SIZE) >> 8;
+}
+
+/**
+ * pci_rebar_set_size - set a new size for a BAR
+ * @pdev: PCI device
+ * @bar: BAR to set size to
+ * @size: new size as defined in the spec (0=1MB, 19=512GB)
+ *
+ * Set the new size of a BAR as defined in the spec.
+ * Returns zero if resizing was successful, error code otherwise.
+ */
+int pci_rebar_set_size(struct pci_dev *pdev, int bar, int size)
+{
+ int pos;
+ u32 ctrl;
+
+ pos = pci_rebar_find_pos(pdev, bar);
+ if (pos < 0)
+ return pos;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ ctrl &= ~PCI_REBAR_CTRL_BAR_SIZE;
+ ctrl |= size << 8;
+ pci_write_config_dword(pdev, pos + PCI_REBAR_CTRL, ctrl);
+ return 0;
+}
+
/**
* pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
* @dev: the PCI device
* All operations are managed and will be undone on driver detach.
*
* Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
- * on failure. Usage example:
+ * on failure. Usage example::
*
* res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
* base = devm_pci_remap_cfg_resource(&pdev->dev, res);
err_handler->reset_done(dev);
}
-/**
- * __pci_reset_function - reset a PCI device function
- * @dev: PCI device to reset
- *
- * Some devices allow an individual function to be reset without affecting
- * other functions in the same device. The PCI device must be responsive
- * to PCI config space in order to use this function.
- *
- * The device function is presumed to be unused when this function is called.
- * Resetting the device will make the contents of PCI configuration space
- * random, so any caller of this must be prepared to reinitialise the
- * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
- * etc.
- *
- * Returns 0 if the device function was successfully reset or negative if the
- * device doesn't support resetting a single function.
- */
-int __pci_reset_function(struct pci_dev *dev)
-{
- int ret;
-
- pci_dev_lock(dev);
- ret = __pci_reset_function_locked(dev);
- pci_dev_unlock(dev);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(__pci_reset_function);
-
/**
* __pci_reset_function_locked - reset a PCI device function while holding
* the @dev mutex lock.
might_sleep();
+ /*
+ * A reset method returns -ENOTTY if it doesn't support this device
+ * and we should try the next method.
+ *
+ * If it returns 0 (success), we're finished. If it returns any
+ * other error, we're also finished: this indicates that further
+ * reset mechanisms might be broken on the device.
+ */
rc = pci_dev_specific_reset(dev, 0);
if (rc != -ENOTTY)
return rc;
*
* This function does not just reset the PCI portion of a device, but
* clears all the state associated with the device. This function differs
- * from __pci_reset_function in that it saves and restores device state
- * over the reset.
+ * from __pci_reset_function_locked() in that it saves and restores device state
+ * over the reset and takes the PCI device lock.
*
* Returns 0 if the device function was successfully reset or negative if the
* device doesn't support resetting a single function.
*
* This function does not just reset the PCI portion of a device, but
* clears all the state associated with the device. This function differs
- * from __pci_reset_function() in that it saves and restores device state
+ * from __pci_reset_function_locked() in that it saves and restores device state
* over the reset. It also differs from pci_reset_function() in that it
* requires the PCI device lock to be held.
*
projects / linux.git / blobdiff