soc/intel/elkhartlake: Use common UART device list driver

Remove platform-specific uart.c and switch to the common UART device
list driver. This eliminates duplicate code.

The elkhartlake uart.c simply defined uart_devices[] array. The common
driver now handles this using the PCI_UART_DEVFNn macro defined in
pci_devs.h.

This commit:
- Adds PCI_DEVFN_UART* aliases pointing to PCH_DEVFN_UART* for naming
  consistency with common code
- Selects SOC_INTEL_COMMON_FEATURE and
  SOC_INTEL_COMMON_FEATURE_UART_DEVICES in Kconfig
- Removes uart.c and updates Makefile.mk

Change-Id: I778faf19128f41509f70d324dd9ccf71d93cab0b
Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/91247
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>

src/soc/intel/elkhartlake/Kconfig

@@ -55,6 +55,8 @@ config SOC_INTEL_ELKHARTLAKE
 	select SOC_INTEL_COMMON_BLOCK_SCS
 	select SOC_INTEL_COMMON_BLOCK_SMM
 	select SOC_INTEL_COMMON_BLOCK_SMM_IO_TRAP
+	select SOC_INTEL_COMMON_FEATURE
+	select SOC_INTEL_COMMON_FEATURE_UART_DEVICES
 	select SOC_INTEL_COMMON_FSP_RESET
 	select SOC_INTEL_COMMON_PCH_CLIENT
 	select SOC_INTEL_COMMON_RESET

src/soc/intel/elkhartlake/Makefile.mk

@@ -10,7 +10,6 @@ all-y += gspi.c
 all-y += i2c.c
 all-y += pmutil.c
 all-y += spi.c
-all-y += uart.c
 
 bootblock-y += bootblock/bootblock.c
 bootblock-y += bootblock/pch.c
@@ -45,7 +44,6 @@ smm-y += gpio.c
 smm-y += p2sb.c
 smm-y += pmutil.c
 smm-y += smihandler.c
-smm-y += uart.c
 
 verstage-y += gpio.c
 

src/soc/intel/elkhartlake/include/soc/pci_devs.h

@@ -247,4 +247,9 @@
 #define  PCH_DEV_SPI		_PCH_DEV(ESPI, 5)
 #define  PCH_DEV_TRACEHUB	_PCH_DEV(ESPI, 7)
 
+/* for common code */
+#define PCI_DEVFN_UART0		PCH_DEVFN_UART0
+#define PCI_DEVFN_UART1		PCH_DEVFN_UART1
+#define PCI_DEVFN_UART2		PCH_DEVFN_UART2
+
 #endif

src/soc/intel/elkhartlake/uart.c

@@ -1,12 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-
-#include <commonlib/helpers.h>
-#include <soc/pci_devs.h>
-
-const unsigned int uart_devices[] = {
-	PCH_DEVFN_UART0,
-	PCH_DEVFN_UART1,
-	PCH_DEVFN_UART2,
-};
-
-const int uart_devices_size = ARRAY_SIZE(uart_devices);