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>

diff --git a/arch/x86/cpu/pci.c b/arch/x86/cpu/pci.c
index c621825..0ccde19 100644 (file)
--- a/arch/x86/cpu/pci.c
+++ b/arch/x86/cpu/pci.c
@@ -16,6 +16,10 @@
 #include <asm/io.h>
 #include <asm/pci.h>
 
+/*
+ * TODO(sjg@chromium.org): Drop the first parameter from each of these
+ * functions since it is not used.
+ */
 int pci_x86_read_config(struct udevice *bus, pci_dev_t bdf, uint offset,
                        ulong *valuep, enum pci_size_t size)
 {
@@ -54,6 +58,21 @@ int pci_x86_write_config(struct udevice *bus, pci_dev_t bdf, uint offset,
        return 0;
 }
 
+int pci_x86_clrset_config(struct udevice *bus, pci_dev_t bdf, uint offset,
+                         ulong clr, ulong set, enum pci_size_t size)
+{
+       ulong value;
+       int ret;
+
+       ret = pci_x86_read_config(bus, bdf, offset, &value, size);
+       if (ret)
+               return ret;
+       value &= ~clr;
+       value |= set;
+
+       return pci_x86_write_config(bus, bdf, offset, value, size);
+}
+
 void pci_assign_irqs(int bus, int device, u8 irq[4])
 {
        pci_dev_t bdf;

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 118ac93..fb1edf3 100644 (file)
--- 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