soc/amd/stoneyridge: Add function to enable I2C host controllers

In preparation for moving AGESA calls out of bootblock:
Add function to enable the four stoneyridge I2C engines.

BUG=b:65442212
BRANCH=master
TEST=abuild, build Gardenia, build and boot Grunt (with other changes
to call code not committed at this time)

Change-Id: Icb55c49cf56c65a9c2e1838cff1ed5afc04e1826
Signed-off-by: Garrett Kirkendall <garrett.kirkendall@amd.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/25026
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/stoneyridge/include/soc/southbridge.h

@@ -344,6 +344,7 @@ struct soc_amd_stoneyridge_gpio {
 
 void sb_enable_rom(void);
 void configure_stoneyridge_uart(void);
+void configure_stoneyridge_i2c(void);
 void sb_clk_output_48Mhz(void);
 void sb_disable_4dw_burst(void);
 void sb_enable(device_t dev);

src/soc/amd/stoneyridge/southbridge.c

@@ -320,6 +320,26 @@ void configure_stoneyridge_uart(void)
 	} while (!status);
 }
 
+void configure_stoneyridge_i2c(void)
+{
+	bool status;
+
+	/* Power on the I2C devices */
+	power_on_aoac_device(FCH_AOAC_D3_CONTROL_I2C0);
+	power_on_aoac_device(FCH_AOAC_D3_CONTROL_I2C1);
+	power_on_aoac_device(FCH_AOAC_D3_CONTROL_I2C2);
+	power_on_aoac_device(FCH_AOAC_D3_CONTROL_I2C3);
+
+	/* Wait for the I2C devices to indicate power and clock OK */
+	do {
+		udelay(100);
+		status = is_aoac_device_enabled(FCH_AOAC_D3_STATE_I2C0);
+		status &= is_aoac_device_enabled(FCH_AOAC_D3_STATE_I2C1);
+		status &= is_aoac_device_enabled(FCH_AOAC_D3_STATE_I2C2);
+		status &= is_aoac_device_enabled(FCH_AOAC_D3_STATE_I2C3);
+	} while (!status);
+}
+
 void sb_pci_port80(void)
 {
 	u8 byte;