pci: Add functions to update PCI configuration registers
It is common to read a config register value, clear and set some bits, then
write back the updated value. Add functions to do this in one step, for
convenience.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
index 519052e..cb51014 100644
--- a/drivers/pci/pci-uclass.c
+++ b/drivers/pci/pci-uclass.c
@@ -250,6 +250,21 @@
return ops->write_config(bus, bdf, offset, value, size);
}
+int pci_bus_clrset_config32(struct udevice *bus, pci_dev_t bdf, int offset,
+ u32 clr, u32 set)
+{
+ ulong val;
+ int ret;
+
+ ret = pci_bus_read_config(bus, bdf, offset, &val, PCI_SIZE_32);
+ if (ret)
+ return ret;
+ val &= ~clr;
+ val |= set;
+
+ return pci_bus_write_config(bus, bdf, offset, val, PCI_SIZE_32);
+}
+
int pci_write_config(pci_dev_t bdf, int offset, unsigned long value,
enum pci_size_t size)
{
@@ -418,6 +433,48 @@
return 0;
}
+int dm_pci_clrset_config8(struct udevice *dev, int offset, u32 clr, u32 set)
+{
+ u8 val;
+ int ret;
+
+ ret = dm_pci_read_config8(dev, offset, &val);
+ if (ret)
+ return ret;
+ val &= ~clr;
+ val |= set;
+
+ return dm_pci_write_config8(dev, offset, val);
+}
+
+int dm_pci_clrset_config16(struct udevice *dev, int offset, u32 clr, u32 set)
+{
+ u16 val;
+ int ret;
+
+ ret = dm_pci_read_config16(dev, offset, &val);
+ if (ret)
+ return ret;
+ val &= ~clr;
+ val |= set;
+
+ return dm_pci_write_config16(dev, offset, val);
+}
+
+int dm_pci_clrset_config32(struct udevice *dev, int offset, u32 clr, u32 set)
+{
+ u32 val;
+ int ret;
+
+ ret = dm_pci_read_config32(dev, offset, &val);
+ if (ret)
+ return ret;
+ val &= ~clr;
+ val |= set;
+
+ return dm_pci_write_config32(dev, offset, val);
+}
+
static void set_vga_bridge_bits(struct udevice *dev)
{
struct udevice *parent = dev->parent;
diff --git a/include/pci.h b/include/pci.h
index 68548b0..db84744 100644
--- a/include/pci.h
+++ b/include/pci.h
@@ -1027,6 +1027,21 @@
unsigned long 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.
+ *
+ * @bus: Bus to access
+ * @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_bus_clrset_config32(struct udevice *bus, pci_dev_t bdf, int offset,
+ u32 clr, u32 set);
+
+/**
* Driver model PCI config access functions. Use these in preference to others
* when you have a valid device
*/
@@ -1044,6 +1059,14 @@
int dm_pci_write_config16(struct udevice *dev, int offset, u16 value);
int dm_pci_write_config32(struct udevice *dev, int offset, u32 value);
+/**
+ * These permit convenient read/modify/write on PCI configuration. The
+ * register is updated to (oldvalue & ~clr) | set.
+ */
+int dm_pci_clrset_config8(struct udevice *dev, int offset, u32 clr, u32 set);
+int dm_pci_clrset_config16(struct udevice *dev, int offset, u32 clr, u32 set);
+int dm_pci_clrset_config32(struct udevice *dev, int offset, u32 clr, u32 set);
+
/*
* The following functions provide access to the above without needing the
* size parameter. We are trying to encourage the use of the 8/16/32-style