include/console/uart: make index parameter unsigned

The UART index is never negative, so make it unsigned and drop the
checks for the index to be non-negative.

Change-Id: I64bd60bd2a3b82552cb3ac6524792b9ac6c09a94
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45294
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

32 files changed, 98 insertions, 98 deletions

diff --git a/src/drivers/uart/oxpcie_early.c b/src/drivers/uart/oxpcie_early.c
index b012c5a77a..ff7d0cfd8a 100644
--- a/src/drivers/uart/oxpcie_early.c
+++ b/src/drivers/uart/oxpcie_early.c
@@ -55,9 +55,9 @@ static int oxpcie_uart_active(void)
 	return oxpcie_present;
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
-	if ((idx >= 0) && (idx < 8) && oxpcie_uart_active())
+	if ((idx < 8) && oxpcie_uart_active())
 		return uart0_base + idx * 0x200;
 	return 0;
 }
diff --git a/src/drivers/uart/pl011.c b/src/drivers/uart/pl011.c
index 2b81e76693..0a73d829ad 100644
--- a/src/drivers/uart/pl011.c
+++ b/src/drivers/uart/pl011.c
@@ -5,11 +5,11 @@
 #include <console/uart.h>
 #include <drivers/uart/pl011.h>
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct pl011_uart *regs = uart_platform_baseptr(idx);
 
@@ -17,7 +17,7 @@ void uart_tx_byte(int idx, unsigned char data)
 	uart_tx_flush(idx);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	struct pl011_uart *regs = uart_platform_baseptr(idx);
 
@@ -26,7 +26,7 @@ void uart_tx_flush(int idx)
 		;
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct pl011_uart *regs = uart_platform_baseptr(idx);
 
diff --git a/src/drivers/uart/sifive.c b/src/drivers/uart/sifive.c
index 0c94c6aeaa..31181aa51f 100644
--- a/src/drivers/uart/sifive.c
+++ b/src/drivers/uart/sifive.c
@@ -45,7 +45,7 @@ static void sifive_uart_init(struct sifive_uart_registers *regs, int div)
 	write32(&regs->rxctrl, RXCTRL_RXEN|RXCTRL_RXCNT(0));
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	unsigned int div;
 	div = uart_baudrate_divisor(get_uart_baudrate(),
@@ -58,7 +58,7 @@ static bool uart_can_tx(struct sifive_uart_registers *regs)
 	return !(read32(&regs->txdata) & TXDATA_FULL);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct sifive_uart_registers *regs = uart_platform_baseptr(idx);
 
@@ -68,7 +68,7 @@ void uart_tx_byte(int idx, unsigned char data)
 	write32(&regs->txdata, data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	struct sifive_uart_registers *regs = uart_platform_baseptr(idx);
 	uint32_t ip;
@@ -79,7 +79,7 @@ void uart_tx_flush(int idx)
 	} while (!(ip & IP_TXWM));
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct sifive_uart_registers *regs = uart_platform_baseptr(idx);
 	uint32_t rxdata;
diff --git a/src/drivers/uart/uart8250io.c b/src/drivers/uart/uart8250io.c
index 22b79e8b6b..d0841de39c 100644
--- a/src/drivers/uart/uart8250io.c
+++ b/src/drivers/uart/uart8250io.c
@@ -77,14 +77,14 @@ static void uart8250_init(unsigned int base_port, unsigned int divisor)
 
 static const unsigned int bases[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (idx < ARRAY_SIZE(bases))
 		return bases[idx];
 	return 0;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	if (!CONFIG(DRIVERS_UART_8250IO_SKIP_INIT)) {
 		unsigned int div;
@@ -94,17 +94,17 @@ void uart_init(int idx)
 	}
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	uart8250_tx_byte(uart_platform_base(idx), data);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return uart8250_rx_byte(uart_platform_base(idx));
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	uart8250_tx_flush(uart_platform_base(idx));
 }
diff --git a/src/drivers/uart/uart8250mem.c b/src/drivers/uart/uart8250mem.c
index 8d73272031..1834095014 100644
--- a/src/drivers/uart/uart8250mem.c
+++ b/src/drivers/uart/uart8250mem.c
@@ -97,7 +97,7 @@ static void uart8250_mem_init(void *base, unsigned int divisor)
 	uart8250_write(base, UART8250_LCR, CONFIG_TTYS0_LCS);
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	void *base = uart_platform_baseptr(idx);
 	if (!base)
@@ -109,7 +109,7 @@ void uart_init(int idx)
 	uart8250_mem_init(base, div);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	void *base = uart_platform_baseptr(idx);
 	if (!base)
@@ -117,7 +117,7 @@ void uart_tx_byte(int idx, unsigned char data)
 	uart8250_mem_tx_byte(base, data);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	void *base = uart_platform_baseptr(idx);
 	if (!base)
@@ -125,7 +125,7 @@ unsigned char uart_rx_byte(int idx)
 	return uart8250_mem_rx_byte(base);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	void *base = uart_platform_baseptr(idx);
 	if (!base)
diff --git a/src/include/console/uart.h b/src/include/console/uart.h
index 9d37886ccd..6126a89d57 100644
--- a/src/include/console/uart.h
+++ b/src/include/console/uart.h
@@ -35,14 +35,14 @@ unsigned int uart_input_clock_divider(void);
 /* Bitbang out one byte on an 8n1 UART through the output function set_tx(). */
 void uart_bitbang_tx_byte(unsigned char data, void (*set_tx)(int line_state));
 
-void uart_init(int idx);
-void uart_tx_byte(int idx, unsigned char data);
-void uart_tx_flush(int idx);
-unsigned char uart_rx_byte(int idx);
+void uart_init(unsigned int idx);
+void uart_tx_byte(unsigned int idx, unsigned char data);
+void uart_tx_flush(unsigned int idx);
+unsigned char uart_rx_byte(unsigned int idx);
 
-uintptr_t uart_platform_base(int idx);
+uintptr_t uart_platform_base(unsigned int idx);
 
-static inline void *uart_platform_baseptr(int idx)
+static inline void *uart_platform_baseptr(unsigned int idx)
 {
 	return (void *)uart_platform_base(idx);
 }
diff --git a/src/mainboard/emulation/qemu-aarch64/mmio.c b/src/mainboard/emulation/qemu-aarch64/mmio.c
index 0cffc282ec..0fac64d234 100644
--- a/src/mainboard/emulation/qemu-aarch64/mmio.c
+++ b/src/mainboard/emulation/qemu-aarch64/mmio.c
@@ -3,7 +3,7 @@
 #include <console/uart.h>
 #include <mainboard/addressmap.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return VIRT_UART_BASE;
 }
diff --git a/src/mainboard/emulation/qemu-armv7/mmio.c b/src/mainboard/emulation/qemu-armv7/mmio.c
index 3f239153db..0f07e7f1ef 100644
--- a/src/mainboard/emulation/qemu-armv7/mmio.c
+++ b/src/mainboard/emulation/qemu-armv7/mmio.c
@@ -4,7 +4,7 @@
 
 #define VEXPRESS_UART0_IO_ADDRESS      (0x10009000)
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return VEXPRESS_UART0_IO_ADDRESS;
 }
diff --git a/src/mainboard/emulation/qemu-power8/uart.c b/src/mainboard/emulation/qemu-power8/uart.c
index c6d7e40fef..4b1bf3287e 100644
--- a/src/mainboard/emulation/qemu-power8/uart.c
+++ b/src/mainboard/emulation/qemu-power8/uart.c
@@ -5,26 +5,26 @@
 #include <boot/coreboot_tables.h>
 
 static uint8_t *buf = (void *)0;
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t) buf;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return 0;
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 }
 
diff --git a/src/mainboard/emulation/qemu-riscv/uart.c b/src/mainboard/emulation/qemu-riscv/uart.c
index 4eee12b933..19a2b0016c 100644
--- a/src/mainboard/emulation/qemu-riscv/uart.c
+++ b/src/mainboard/emulation/qemu-riscv/uart.c
@@ -4,7 +4,7 @@
 #include <console/uart.h>
 #include <mainboard/addressmap.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t) QEMU_VIRT_UART0;
 }
diff --git a/src/mainboard/emulation/spike-riscv/uart.c b/src/mainboard/emulation/spike-riscv/uart.c
index d6e0510274..efefc52d62 100644
--- a/src/mainboard/emulation/spike-riscv/uart.c
+++ b/src/mainboard/emulation/spike-riscv/uart.c
@@ -3,7 +3,7 @@
 #include <types.h>
 #include <console/uart.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t) 0x02100000;
 }
diff --git a/src/soc/amd/picasso/uart_console.c b/src/soc/amd/picasso/uart_console.c
index 3ab2a70920..b5c5159486 100644
--- a/src/soc/amd/picasso/uart_console.c
+++ b/src/soc/amd/picasso/uart_console.c
@@ -8,7 +8,7 @@
  * be provided exactly once and only by the UART that is used for console.
  */
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return get_uart_base(idx);
 }
diff --git a/src/soc/amd/stoneyridge/uart.c b/src/soc/amd/stoneyridge/uart.c
index ab129c5f05..73346ab658 100644
--- a/src/soc/amd/stoneyridge/uart.c
+++ b/src/soc/amd/stoneyridge/uart.c
@@ -3,7 +3,7 @@
 #include <console/uart.h>
 #include <soc/southbridge.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (CONFIG_UART_FOR_CONSOLE < 0 || CONFIG_UART_FOR_CONSOLE > 1)
 		return 0;
diff --git a/src/soc/cavium/cn81xx/uart.c b/src/soc/cavium/cn81xx/uart.c
index 03f94d57ac..4e5fd82a37 100644
--- a/src/soc/cavium/cn81xx/uart.c
+++ b/src/soc/cavium/cn81xx/uart.c
@@ -94,7 +94,7 @@ unsigned int uart_platform_refclk(void)
 	return uart_hclk(uart);
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return CONFIG_CONSOLE_SERIAL_UART_ADDRESS;
 }
diff --git a/src/soc/intel/common/block/uart/uart.c b/src/soc/intel/common/block/uart/uart.c
index 5507663a5a..142a9365a9 100644
--- a/src/soc/intel/common/block/uart/uart.c
+++ b/src/soc/intel/common/block/uart/uart.c
@@ -37,7 +37,7 @@ static void uart_lpss_init(const struct device *dev, uintptr_t baseaddr)
 }
 
 #if CONFIG(INTEL_LPSS_UART_FOR_CONSOLE)
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (idx == CONFIG_UART_FOR_CONSOLE)
 		return CONFIG_CONSOLE_UART_BASE_ADDRESS;
diff --git a/src/soc/intel/denverton_ns/uart_debug.c b/src/soc/intel/denverton_ns/uart_debug.c
index 8ee02cca7f..acd1f038c3 100644
--- a/src/soc/intel/denverton_ns/uart_debug.c
+++ b/src/soc/intel/denverton_ns/uart_debug.c
@@ -8,9 +8,9 @@
 #define MY_PCI_DEV(SEGBUS, DEV, FN) \
 	((((SEGBUS)&0xFFF) << 20) | (((DEV)&0x1F) << 15) | (((FN)&0x07) << 12))
 
-uintptr_t uart_platform_base(int idx);
+uintptr_t uart_platform_base(unsigned int idx);
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t)pci_io_read_config32(
 		       MY_PCI_DEV(0, CONFIG_HSUART_DEV, idx),
diff --git a/src/soc/intel/quark/uart_common.c b/src/soc/intel/quark/uart_common.c
index 8696277ce1..19ca745ca1 100644
--- a/src/soc/intel/quark/uart_common.c
+++ b/src/soc/intel/quark/uart_common.c
@@ -8,7 +8,7 @@ unsigned int uart_platform_refclk(void)
 	return 44236800;
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return UART_BASE_ADDRESS;
 }
diff --git a/src/soc/mediatek/common/uart.c b/src/soc/mediatek/common/uart.c
index 99cba13b24..ba3c71a8c6 100644
--- a/src/soc/mediatek/common/uart.c
+++ b/src/soc/mediatek/common/uart.c
@@ -139,22 +139,22 @@ static int mtk_uart_tst_byte(void)
 	return (read8(&uart_ptr->lsr) & UART8250_LSR_DR) == UART8250_LSR_DR;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	mtk_uart_init();
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return mtk_uart_rx_byte();
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	mtk_uart_tx_byte(data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	mtk_uart_tx_flush();
 }
diff --git a/src/soc/nvidia/tegra124/uart.c b/src/soc/nvidia/tegra124/uart.c
index d016cc2618..4f24c0da66 100644
--- a/src/soc/nvidia/tegra124/uart.c
+++ b/src/soc/nvidia/tegra124/uart.c
@@ -76,12 +76,12 @@ static int tegra124_uart_tst_byte(struct tegra124_uart *uart_ptr)
 	return (read8(&uart_ptr->lsr) & UART8250_LSR_DR) == UART8250_LSR_DR;
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	//Default to UART A
 	unsigned int base = 0x70006000;
 	//UARTs A - E are mapped as index 0 - 4
-	if ((idx < 5) && (idx >= 0)) {
+	if ((idx < 5)) {
 		if (idx != 1) { //not UART B
 			base += idx * 0x100;
 		} else {
@@ -91,25 +91,25 @@ uintptr_t uart_platform_base(int idx)
 	return base;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	struct tegra124_uart *uart_ptr = uart_platform_baseptr(idx);
 	tegra124_uart_init(uart_ptr);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct tegra124_uart *uart_ptr = uart_platform_baseptr(idx);
 	return tegra124_uart_rx_byte(uart_ptr);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct tegra124_uart *uart_ptr = uart_platform_baseptr(idx);
 	tegra124_uart_tx_byte(uart_ptr, data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	struct tegra124_uart *uart_ptr = uart_platform_baseptr(idx);
 	tegra124_uart_tx_flush(uart_ptr);
diff --git a/src/soc/nvidia/tegra210/uart.c b/src/soc/nvidia/tegra210/uart.c
index 865e1fafe1..7dbaf7b207 100644
--- a/src/soc/nvidia/tegra210/uart.c
+++ b/src/soc/nvidia/tegra210/uart.c
@@ -82,22 +82,22 @@ static int tegra210_uart_tst_byte(void)
 	return (read8(&uart_ptr->lsr) & UART8250_LSR_DR) == UART8250_LSR_DR;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	tegra210_uart_init();
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	tegra210_uart_tx_byte(data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	tegra210_uart_tx_flush();
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return tegra210_uart_rx_byte();
 }
diff --git a/src/soc/qualcomm/ipq40xx/uart.c b/src/soc/qualcomm/ipq40xx/uart.c
index 265c25e28b..9c506111fa 100644
--- a/src/soc/qualcomm/ipq40xx/uart.c
+++ b/src/soc/qualcomm/ipq40xx/uart.c
@@ -87,7 +87,7 @@ static int valid_data = 0;
 /* Received data */
 static unsigned int word = 0;
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	int num_of_chars = 1;
 	void *base = uart_board_param.uart_dm_base;
@@ -195,7 +195,7 @@ unsigned int msm_boot_uart_dm_init(void  *uart_dm_base)
  *
  * Initializes clocks, GPIO and UART controller.
  */
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	/* Note int idx isn't used in this driver. */
 	void *dm_base;
@@ -230,7 +230,7 @@ void ipq40xx_uart_init(void)
  * @brief uart_tx_flush - transmits a string of data
  * @param idx: string to transmit
  */
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	void *base = uart_board_param.uart_dm_base;
 
@@ -244,7 +244,7 @@ void uart_tx_flush(int idx)
  *
  * Returns the character read from serial port.
  */
-uint8_t uart_rx_byte(int idx)
+uint8_t uart_rx_byte(unsigned int idx)
 {
 	uint8_t byte;
 
diff --git a/src/soc/qualcomm/ipq806x/uart.c b/src/soc/qualcomm/ipq806x/uart.c
index ea564b3527..3a3a8bf27b 100644
--- a/src/soc/qualcomm/ipq806x/uart.c
+++ b/src/soc/qualcomm/ipq806x/uart.c
@@ -160,7 +160,7 @@ msm_boot_uart_dm_read(unsigned int *data, int *count, int wait)
 }
 #endif
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	int num_of_chars = 1;
 	unsigned int tx_data = 0;
@@ -269,7 +269,7 @@ static unsigned int msm_boot_uart_dm_init(void  *uart_dm_base)
  *
  * Initializes clocks, GPIO and UART controller.
  */
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	/* Note int idx isn't used in this driver. */
 	void *dm_base;
@@ -316,7 +316,7 @@ uint32_t uartmem_getbaseaddr(void)
  * uart_tx_flush - transmits a string of data
  * @s: string to transmit
  */
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	void *base = uart_board_param.uart_dm_base;
 
@@ -351,7 +351,7 @@ int uart_can_rx_byte(void)
  *
  * Returns the character read from serial port.
  */
-uint8_t uart_rx_byte(int idx)
+uint8_t uart_rx_byte(unsigned int idx)
 {
 	uint8_t byte;
 
diff --git a/src/soc/qualcomm/qcs405/uart.c b/src/soc/qualcomm/qcs405/uart.c
index 1229053783..ac72998cb6 100644
--- a/src/soc/qualcomm/qcs405/uart.c
+++ b/src/soc/qualcomm/qcs405/uart.c
@@ -90,7 +90,7 @@ static int valid_data = 0;
 static unsigned int word = 0;
 
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	int num_of_chars = 1;
 	void *base = uart_board_param.uart_dm_base;
@@ -199,7 +199,7 @@ unsigned int msm_boot_uart_dm_init(void  *uart_dm_base)
  *
  * Initializes clocks, GPIO and UART controller.
  */
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	/* Note int idx isn't used in this driver. */
 	void *dm_base;
@@ -231,7 +231,7 @@ void qcs405_uart_init(void)
  * @brief uart_tx_flush - transmits a string of data
  * @param idx: string to transmit
  */
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	void *base = uart_board_param.uart_dm_base;
 
@@ -246,7 +246,7 @@ void uart_tx_flush(int idx)
  *
  * Returns the character read from serial port.
  */
-uint8_t uart_rx_byte(int idx)
+uint8_t uart_rx_byte(unsigned int idx)
 {
 	uint8_t byte;
 
diff --git a/src/soc/qualcomm/sc7180/qupv3_uart.c b/src/soc/qualcomm/sc7180/qupv3_uart.c
index f9d99bb71e..bf274c23c9 100644
--- a/src/soc/qualcomm/sc7180/qupv3_uart.c
+++ b/src/soc/qualcomm/sc7180/qupv3_uart.c
@@ -34,7 +34,7 @@
 #define UART_RX_PACK_VECTOR0	0xF
 #define UART_RX_PACK_VECTOR2	0x00
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	struct qup_regs *regs = qup[idx].regs;
 
@@ -43,7 +43,7 @@ void uart_tx_flush(int idx)
 		;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	struct qup_regs *regs = qup[idx].regs;
 	unsigned int reg_value;
@@ -113,7 +113,7 @@ void uart_init(int idx)
 	write32(&regs->geni_s_cmd0, START_UART_RX);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct qup_regs *regs = qup[idx].regs;
 
@@ -122,7 +122,7 @@ unsigned char uart_rx_byte(int idx)
 	return 0;
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct qup_regs *regs = qup[idx].regs;
 
@@ -134,7 +134,7 @@ void uart_tx_byte(int idx, unsigned char data)
 	write32(&regs->geni_tx_fifon, data);
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t)qup[idx].regs;
 }
diff --git a/src/soc/qualcomm/sc7180/uart_bitbang.c b/src/soc/qualcomm/sc7180/uart_bitbang.c
index b3a6cd5870..7d88a20986 100644
--- a/src/soc/qualcomm/sc7180/uart_bitbang.c
+++ b/src/soc/qualcomm/sc7180/uart_bitbang.c
@@ -16,22 +16,22 @@ static void set_tx(int line_state)
 	gpio_set(UART_TX_PIN, line_state);
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	gpio_output(UART_TX_PIN, 1);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	uart_bitbang_tx_byte(data, set_tx);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	/* unnecessary, PIO Tx means transaction is over when tx_byte returns */
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return 0;	/* not implemented */
 }
diff --git a/src/soc/qualcomm/sdm845/uart_bitbang.c b/src/soc/qualcomm/sdm845/uart_bitbang.c
index b78db833a4..8d7138e5d1 100644
--- a/src/soc/qualcomm/sdm845/uart_bitbang.c
+++ b/src/soc/qualcomm/sdm845/uart_bitbang.c
@@ -10,22 +10,22 @@ static void set_tx(int line_state)
 	gpio_set(UART_TX_PIN, line_state);
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	gpio_output(UART_TX_PIN, 1);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	uart_bitbang_tx_byte(data, set_tx);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	/* unnecessary, PIO Tx means transaction is over when tx_byte returns */
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	return 0;	/* not implemented */
 }
diff --git a/src/soc/rockchip/common/uart.c b/src/soc/rockchip/common/uart.c
index 2c6d6cec68..b98f182d7c 100644
--- a/src/soc/rockchip/common/uart.c
+++ b/src/soc/rockchip/common/uart.c
@@ -9,7 +9,7 @@ unsigned int uart_platform_refclk(void)
 	return OSC_HZ;
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return CONFIG_CONSOLE_SERIAL_UART_ADDRESS;
 }
diff --git a/src/soc/samsung/exynos5250/uart.c b/src/soc/samsung/exynos5250/uart.c
index 326312576b..ef03c04f23 100644
--- a/src/soc/samsung/exynos5250/uart.c
+++ b/src/soc/samsung/exynos5250/uart.c
@@ -100,7 +100,7 @@ static void exynos5_uart_tx_flush(struct s5p_uart *uart)
 	while (read32(&uart->ufstat) & 0x1ff0000);
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (idx < 4)
 		return 0x12c00000 + idx * 0x10000;
@@ -108,25 +108,25 @@ uintptr_t uart_platform_base(int idx)
 		return 0;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	exynos5_init_dev(uart);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	return exynos5_uart_rx_byte(uart);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	exynos5_uart_tx_byte(uart, data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	exynos5_uart_tx_flush(uart);
diff --git a/src/soc/samsung/exynos5420/uart.c b/src/soc/samsung/exynos5420/uart.c
index c7a0649f5d..16a4b11da3 100644
--- a/src/soc/samsung/exynos5420/uart.c
+++ b/src/soc/samsung/exynos5420/uart.c
@@ -92,7 +92,7 @@ static void exynos5_uart_tx_byte(struct s5p_uart *uart, unsigned char data)
 	write8(&uart->utxh, data);
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (idx < 4)
 		return 0x12c00000 + idx * 0x10000;
@@ -100,25 +100,25 @@ uintptr_t uart_platform_base(int idx)
 		return 0;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	exynos5_init_dev(uart);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	return exynos5_uart_rx_byte(uart);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct s5p_uart *uart = uart_platform_baseptr(idx);
 	exynos5_uart_tx_byte(uart, data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 	/* Exynos5250 implements this too. */
 }
diff --git a/src/soc/sifive/fu540/uart.c b/src/soc/sifive/fu540/uart.c
index c35e0f6166..353f6cd624 100644
--- a/src/soc/sifive/fu540/uart.c
+++ b/src/soc/sifive/fu540/uart.c
@@ -6,7 +6,7 @@
 #include <soc/addressmap.h>
 #include <soc/clock.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	if (idx < 2)
 		return FU540_UART(idx);
diff --git a/src/soc/ti/am335x/uart.c b/src/soc/ti/am335x/uart.c
index 90095d47d9..e3648a93a6 100644
--- a/src/soc/ti/am335x/uart.c
+++ b/src/soc/ti/am335x/uart.c
@@ -135,7 +135,7 @@ unsigned int uart_platform_refclk(void)
 	return 48000000;
 }
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	const unsigned int bases[] = {
 		0x44e09000, 0x48022000, 0x48024000,
@@ -146,7 +146,7 @@ uintptr_t uart_platform_base(int idx)
 	return 0;
 }
 
-void uart_init(int idx)
+void uart_init(unsigned int idx)
 {
 	struct am335x_uart *uart = uart_platform_baseptr(idx);
 	uint16_t div = (uint16_t) uart_baudrate_divisor(
@@ -154,19 +154,19 @@ void uart_init(int idx)
 	am335x_uart_init(uart, div);
 }
 
-unsigned char uart_rx_byte(int idx)
+unsigned char uart_rx_byte(unsigned int idx)
 {
 	struct am335x_uart *uart = uart_platform_baseptr(idx);
 	return am335x_uart_rx_byte(uart);
 }
 
-void uart_tx_byte(int idx, unsigned char data)
+void uart_tx_byte(unsigned int idx, unsigned char data)
 {
 	struct am335x_uart *uart = uart_platform_baseptr(idx);
 	am335x_uart_tx_byte(uart, data);
 }
 
-void uart_tx_flush(int idx)
+void uart_tx_flush(unsigned int idx)
 {
 }
 
diff --git a/src/southbridge/amd/pi/hudson/uart.c b/src/southbridge/amd/pi/hudson/uart.c
index 2d28210569..996215de34 100644
--- a/src/southbridge/amd/pi/hudson/uart.c
+++ b/src/southbridge/amd/pi/hudson/uart.c
@@ -2,7 +2,7 @@
 
 #include <console/uart.h>
 
-uintptr_t uart_platform_base(int idx)
+uintptr_t uart_platform_base(unsigned int idx)
 {
 	return (uintptr_t)(0xFEDC6000 + 0x2000 * (idx & 1));
 }