soc/intel/common/block/uart: Update the UART PCI device reference

This implementation revises the UART PCI device reference in common
UART driver. The SOC functions have been aligned to provide the UART
PCI device reference using pcidev_path_on_root.

The uart_get_device() return type is changed, and files in which
it gets used are updated.

Change-Id: Ie0fe5991f3b0b9c596c3de9472e98e4091d7dd87
Signed-off-by: Aamir Bohra <aamir.bohra@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34582
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

6 files changed, 38 insertions, 31 deletions

diff --git a/src/soc/intel/apollolake/uart.c b/src/soc/intel/apollolake/uart.c
index 27be4e65f9..f8c4aafec2 100644
--- a/src/soc/intel/apollolake/uart.c
+++ b/src/soc/intel/apollolake/uart.c
@@ -74,7 +74,7 @@ const struct uart_gpio_pad_config uart_gpio_pads[] = {
 
 const int uart_max_index = ARRAY_SIZE(uart_gpio_pads);
 
-struct device *soc_uart_console_to_device(int uart_console)
+DEVTREE_CONST struct device *soc_uart_console_to_device(int uart_console)
 {
 	/*
 	 * if index is valid, this function will return corresponding structure
@@ -82,13 +82,13 @@ struct device *soc_uart_console_to_device(int uart_console)
 	 */
 	switch (uart_console) {
 	case 0:
-		return (struct device *)PCH_DEV_UART0;
+		return pcidev_path_on_root(PCH_DEVFN_UART0);
 	case 1:
-		return (struct device *)PCH_DEV_UART1;
+		return pcidev_path_on_root(PCH_DEVFN_UART1);
 	case 2:
-		return (struct device *)PCH_DEV_UART2;
+		return pcidev_path_on_root(PCH_DEVFN_UART2);
 	case 3:
-		return (struct device *)PCH_DEV_UART3;
+		return pcidev_path_on_root(PCH_DEVFN_UART3);
 	default:
 		printk(BIOS_ERR, "Invalid UART console index\n");
 		return NULL;
diff --git a/src/soc/intel/cannonlake/uart.c b/src/soc/intel/cannonlake/uart.c
index 7174a9a58f..ae19acc264 100644
--- a/src/soc/intel/cannonlake/uart.c
+++ b/src/soc/intel/cannonlake/uart.c
@@ -50,7 +50,7 @@ const struct uart_gpio_pad_config uart_gpio_pads[] = {
 
 const int uart_max_index = ARRAY_SIZE(uart_gpio_pads);
 
-struct device *soc_uart_console_to_device(int uart_console)
+DEVTREE_CONST struct device *soc_uart_console_to_device(int uart_console)
 {
 	/*
 	 * if index is valid, this function will return corresponding structure
@@ -58,11 +58,11 @@ struct device *soc_uart_console_to_device(int uart_console)
 	 */
 	switch (uart_console) {
 	case 0:
-		return (struct device *)PCH_DEV_UART0;
+		return pcidev_path_on_root(PCH_DEVFN_UART0);
 	case 1:
-		return (struct device *)PCH_DEV_UART1;
+		return pcidev_path_on_root(PCH_DEVFN_UART1);
 	case 2:
-		return (struct device *)PCH_DEV_UART2;
+		return pcidev_path_on_root(PCH_DEVFN_UART2);
 	default:
 		printk(BIOS_ERR, "Invalid UART console index\n");
 		return NULL;
diff --git a/src/soc/intel/common/block/include/intelblocks/uart.h b/src/soc/intel/common/block/include/intelblocks/uart.h
index 55f259db7c..1b62421d2b 100644
--- a/src/soc/intel/common/block/include/intelblocks/uart.h
+++ b/src/soc/intel/common/block/include/intelblocks/uart.h
@@ -40,7 +40,7 @@ struct uart_gpio_pad_config {
  * Common routine to initialize UART controller PCI config space, take it out of
  * reset and configure M/N dividers.
  */
-void uart_common_init(struct device *dev, uintptr_t baseaddr);
+void uart_common_init(const struct device *dev, uintptr_t baseaddr);
 
 /*
  * Check if UART debug controller is initialized
@@ -72,7 +72,7 @@ void uart_bootblock_init(void);
  * Pointer to device structure = If device has a UART debug controller.
  * NULL = otherwise
  */
-struct device *uart_get_device(void);
+const struct device *uart_get_device(void);
 
 /**************************** SoC callbacks ***********************************/
 
@@ -89,6 +89,6 @@ struct device *uart_get_device(void);
  * Pointer to device structure = If device has a UART debug controller.
  * NULL = otherwise
  */
-struct device *soc_uart_console_to_device(int uart_console);
+DEVTREE_CONST struct device *soc_uart_console_to_device(int uart_console);
 
 #endif	/* SOC_INTEL_COMMON_BLOCK_UART_H */
diff --git a/src/soc/intel/common/block/uart/uart.c b/src/soc/intel/common/block/uart/uart.c
index 9d820ffd7e..f556aed3d6 100644
--- a/src/soc/intel/common/block/uart/uart.c
+++ b/src/soc/intel/common/block/uart/uart.c
@@ -65,15 +65,13 @@ static int uart_get_valid_index(void)
 	return UART_CONSOLE_INVALID_INDEX;
 }
 
-void uart_common_init(struct device *device, uintptr_t baseaddr)
+void uart_common_init(const struct device *device, uintptr_t baseaddr)
 {
 #if defined(__SIMPLE_DEVICE__)
-	pci_devfn_t dev = (pci_devfn_t)(uintptr_t)device;
+	pci_devfn_t dev = PCI_BDF(device);
 #else
-	struct device *dev = device;
+	const struct device *dev = device;
 #endif
-	if (!dev)
-		return;
 
 	/* Set UART base address */
 	pci_write_config32(dev, PCI_BASE_ADDRESS_0, baseaddr);
@@ -84,7 +82,7 @@ void uart_common_init(struct device *device, uintptr_t baseaddr)
 	uart_lpss_init(baseaddr);
 }
 
-struct device *uart_get_device(void)
+const struct device *uart_get_device(void)
 {
 	/*
 	 * This function will get called even if INTEL_LPSS_UART_FOR_CONSOLE
@@ -105,14 +103,16 @@ struct device *uart_get_device(void)
 bool uart_is_controller_initialized(void)
 {
 	uintptr_t base;
+	const struct device *dev_uart = uart_get_device();
+
+	if (!dev_uart)
+		return false;
 
 #if defined(__SIMPLE_DEVICE__)
-	pci_devfn_t dev = (pci_devfn_t)(uintptr_t)uart_get_device();
+	pci_devfn_t dev = PCI_BDF(dev_uart);
 #else
-	struct device *dev = uart_get_device();
+	const struct device *dev = dev_uart;
 #endif
-	if (!dev)
-		return false;
 
 	base = pci_read_config32(dev, PCI_BASE_ADDRESS_0) & ~0xFFF;
 	if (!base)
@@ -136,8 +136,15 @@ static void uart_configure_gpio_pads(void)
 
 void uart_bootblock_init(void)
 {
+	const struct device *dev_uart;
+
+	dev_uart = uart_get_device();
+
+	if (!dev_uart)
+		return;
+
 	/* Program UART BAR0, command, reset and clock register */
-	uart_common_init(uart_get_device(), CONFIG_CONSOLE_UART_BASE_ADDRESS);
+	uart_common_init(dev_uart, CONFIG_CONSOLE_UART_BASE_ADDRESS);
 
 	/* Configure the 2 pads per UART. */
 	uart_configure_gpio_pads();
diff --git a/src/soc/intel/icelake/uart.c b/src/soc/intel/icelake/uart.c
index 7174a9a58f..ae19acc264 100644
--- a/src/soc/intel/icelake/uart.c
+++ b/src/soc/intel/icelake/uart.c
@@ -50,7 +50,7 @@ const struct uart_gpio_pad_config uart_gpio_pads[] = {
 
 const int uart_max_index = ARRAY_SIZE(uart_gpio_pads);
 
-struct device *soc_uart_console_to_device(int uart_console)
+DEVTREE_CONST struct device *soc_uart_console_to_device(int uart_console)
 {
 	/*
 	 * if index is valid, this function will return corresponding structure
@@ -58,11 +58,11 @@ struct device *soc_uart_console_to_device(int uart_console)
 	 */
 	switch (uart_console) {
 	case 0:
-		return (struct device *)PCH_DEV_UART0;
+		return pcidev_path_on_root(PCH_DEVFN_UART0);
 	case 1:
-		return (struct device *)PCH_DEV_UART1;
+		return pcidev_path_on_root(PCH_DEVFN_UART1);
 	case 2:
-		return (struct device *)PCH_DEV_UART2;
+		return pcidev_path_on_root(PCH_DEVFN_UART2);
 	default:
 		printk(BIOS_ERR, "Invalid UART console index\n");
 		return NULL;
diff --git a/src/soc/intel/skylake/uart.c b/src/soc/intel/skylake/uart.c
index 8b7c99eae5..18fcf1b194 100644
--- a/src/soc/intel/skylake/uart.c
+++ b/src/soc/intel/skylake/uart.c
@@ -51,7 +51,7 @@ const struct uart_gpio_pad_config uart_gpio_pads[] = {
 
 const int uart_max_index = ARRAY_SIZE(uart_gpio_pads);
 
-struct device *soc_uart_console_to_device(int uart_console)
+DEVTREE_CONST struct device *soc_uart_console_to_device(int uart_console)
 {
 	/*
 	 * if index is valid, this function will return corresponding structure
@@ -59,11 +59,11 @@ struct device *soc_uart_console_to_device(int uart_console)
 	 */
 	switch (uart_console) {
 	case 0:
-		return (struct device *)PCH_DEV_UART0;
+		return pcidev_path_on_root(PCH_DEVFN_UART0);
 	case 1:
-		return (struct device *)PCH_DEV_UART1;
+		return pcidev_path_on_root(PCH_DEVFN_UART1);
 	case 2:
-		return (struct device *)PCH_DEV_UART2;
+		return pcidev_path_on_root(PCH_DEVFN_UART2);
 	default:
 		printk(BIOS_ERR, "Invalid UART console index\n");
 		return NULL;