lynxpoint: Enable SerialIO clock in PCI mode
The clock gating register at offset 0x800 is managed by the
clock driver in the kernel when the devices are in ACPI mode.
When in PCI mode we should force enable the clock here.
When in ACPI mode or the device is disabled it should be put
in D3Hot state.
> i2cdetect -y -r 10
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
Change-Id: Ib93ffd41bf36386d5ce63bfc0ae6597f3e23bc48
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/56122
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/4180
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/southbridge/intel/lynxpoint/serialio.c b/src/southbridge/intel/lynxpoint/serialio.c
index 11d6a36..8257cc2 100644
--- a/src/southbridge/intel/lynxpoint/serialio.c
+++ b/src/southbridge/intel/lynxpoint/serialio.c
@@ -29,6 +29,22 @@
#include "pch.h"
#include "nvs.h"
+/* Set D3Hot Power State in ACPI mode */
+static void serialio_enable_d3hot(struct device *dev)
+{
+ u32 reg32 = pci_read_config32(dev, PCH_PCS);
+ reg32 |= PCH_PCS_PS_D3HOT;
+ pci_write_config32(dev, PCH_PCS, reg32);
+}
+
+/* Enable clock in PCI mode */
+static void serialio_enable_clock(struct resource *bar0)
+{
+ u32 reg32 = read32(bar0->base + SIO_REG_PPR_CLOCK);
+ reg32 |= SIO_REG_PPR_CLOCK_EN;
+ write32(bar0->base + SIO_REG_PPR_CLOCK, reg32);
+}
+
/* Put Serial IO D21:F0-F6 device into desired mode. */
static void serialio_d21_mode(int sio_index, int int_pin, int acpi_mode)
{
@@ -143,9 +159,15 @@
struct southbridge_intel_lynxpoint_config *config = dev->chip_info;
struct resource *bar0, *bar1;
int sio_index = -1;
+ u32 reg32;
printk(BIOS_DEBUG, "Initializing Serial IO device\n");
+ /* Ensure memory and bus master are enabled */
+ reg32 = pci_read_config32(dev, PCI_COMMAND);
+ reg32 |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
+ pci_write_config32(dev, PCI_COMMAND, reg32);
+
/* Find BAR0 and BAR1 */
bar0 = find_resource(dev, PCI_BASE_ADDRESS_0);
if (!bar0)
@@ -154,6 +176,11 @@
if (!bar1)
return;
+ if (!config->sio_acpi_mode)
+ serialio_enable_clock(bar0);
+ else if (dev->path.pci.devfn != PCI_DEVFN(21, 0))
+ serialio_enable_d3hot(dev); /* all but SDMA */
+
switch (dev->path.pci.devfn) {
case PCI_DEVFN(21, 0): /* SDMA */
sio_index = SIO_ID_SDMA;
@@ -241,9 +268,9 @@
};
static struct device_operations device_ops = {
- .read_resources = pci_bus_read_resources,
+ .read_resources = pci_dev_read_resources,
.set_resources = pci_dev_set_resources,
- .enable_resources = pci_bus_enable_resources,
+ .enable_resources = pci_dev_enable_resources,
.init = serialio_init,
.ops_pci = &pci_ops,
};