x86: pci: Add a function to clear and set PCI config regs

At present the x86 pre-DM equivalent of pci_bus_clrset_config32() does not
exist. Add it to simplify PCI init code on x86.

Also add the missing functions to this header.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 118ac937d9..fb1edf3df7 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -17,13 +17,53 @@
 
 #ifndef __ASSEMBLY__
 
+/**
+ * pci_x86_read_config() - Read a configuration value from a device
+ *
+ * This function can be called before PCI is set up in driver model.
+ *
+ * @bus:	Bus to read from (ignored, can be NULL)
+ * @bdf:	PCI device address: bus, device and function -see PCI_BDF()
+ * @offset:	Register offset to read
+ * @valuep:	Place to put the returned value
+ * @size:	Access size
+ * @return 0 if OK, -ve on error
+ */
 int pci_x86_read_config(struct udevice *bus, pci_dev_t bdf, uint offset,
 			ulong *valuep, enum pci_size_t size);
 
+/**
+ * pci_bus_write_config() - Write a configuration value to a device
+ *
+ * This function can be called before PCI is set up in driver model.
+ *
+ * @bus:	Bus to read from (ignored, can be NULL)
+ * @bdf:	PCI device address: bus, device and function -see PCI_BDF()
+ * @offset:	Register offset to write
+ * @value:	Value to write
+ * @size:	Access size
+ * @return 0 if OK, -ve on error
+ */
 int pci_x86_write_config(struct udevice *bus, pci_dev_t bdf, uint offset,
 			 ulong value, enum pci_size_t size);
 
 /**
+ * pci_bus_clrset_config32() - Update a configuration value for a device
+ *
+ * The register at @offset is updated to (oldvalue & ~clr) | set. This function
+ * can be called before PCI is set up in driver model.
+ *
+ * @bus:	Bus to read from (ignored, can be NULL)
+ * @bdf:	PCI device address: bus, device and function -see PCI_BDF()
+ * @offset:	Register offset to update
+ * @clr:	Bits to clear
+ * @set:	Bits to set
+ * @return 0 if OK, -ve on error
+ */
+int pci_x86_clrset_config(struct udevice *bus, pci_dev_t bdf, uint offset,
+			  ulong clr, ulong set, enum pci_size_t size);
+
+/**
  * Assign IRQ number to a PCI device
  *
  * This function assigns IRQ for a PCI device. If the device does not exist