diff options
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/atmel_usart.c | 84 |
1 files changed, 78 insertions, 6 deletions
diff --git a/drivers/serial/atmel_usart.c b/drivers/serial/atmel_usart.c index 7674f97e8d..453f8eb451 100644 --- a/drivers/serial/atmel_usart.c +++ b/drivers/serial/atmel_usart.c @@ -7,6 +7,7 @@ * SPDX-License-Identifier: GPL-2.0+ */ #include <common.h> +#include <clk.h> #include <dm.h> #include <errno.h> #include <watchdog.h> @@ -25,6 +26,7 @@ DECLARE_GLOBAL_DATA_PTR; +#ifndef CONFIG_DM_SERIAL static void atmel_serial_setbrg_internal(atmel_usart3_t *usart, int id, int baudrate) { @@ -66,7 +68,6 @@ static void atmel_serial_activate(atmel_usart3_t *usart) __udelay(100); } -#ifndef CONFIG_DM_SERIAL static void atmel_serial_setbrg(void) { atmel_serial_setbrg_internal((atmel_usart3_t *)CONFIG_USART_BASE, @@ -133,17 +134,47 @@ __weak struct serial_device *default_serial_console(void) #endif #ifdef CONFIG_DM_SERIAL +enum serial_clk_type { + CLK_TYPE_NORMAL = 0, + CLK_TYPE_DBGU, +}; struct atmel_serial_priv { atmel_usart3_t *usart; + ulong usart_clk_rate; }; +static void _atmel_serial_set_brg(atmel_usart3_t *usart, + ulong usart_clk_rate, int baudrate) +{ + unsigned long divisor; + + divisor = (usart_clk_rate / 16 + baudrate / 2) / baudrate; + writel(USART3_BF(CD, divisor), &usart->brgr); +} + +void _atmel_serial_init(atmel_usart3_t *usart, + ulong usart_clk_rate, int baudrate) +{ + writel(USART3_BIT(RXDIS) | USART3_BIT(TXDIS), &usart->cr); + + writel((USART3_BF(USART_MODE, USART3_USART_MODE_NORMAL) | + USART3_BF(USCLKS, USART3_USCLKS_MCK) | + USART3_BF(CHRL, USART3_CHRL_8) | + USART3_BF(PAR, USART3_PAR_NONE) | + USART3_BF(NBSTOP, USART3_NBSTOP_1)), &usart->mr); + + _atmel_serial_set_brg(usart, usart_clk_rate, baudrate); + + writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr); + writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr); +} + int atmel_serial_setbrg(struct udevice *dev, int baudrate) { struct atmel_serial_priv *priv = dev_get_priv(dev); - atmel_serial_setbrg_internal(priv->usart, 0 /* ignored */, baudrate); - atmel_serial_activate(priv->usart); + _atmel_serial_set_brg(priv->usart, priv->usart_clk_rate, baudrate); return 0; } @@ -188,10 +219,39 @@ static const struct dm_serial_ops atmel_serial_ops = { .setbrg = atmel_serial_setbrg, }; +static int atmel_serial_enable_clk(struct udevice *dev) +{ + struct atmel_serial_priv *priv = dev_get_priv(dev); + struct clk clk; + ulong clk_rate; + int ret; + + ret = clk_get_by_index(dev, 0, &clk); + if (ret) + return -EINVAL; + + if (dev_get_driver_data(dev) == CLK_TYPE_NORMAL) { + ret = clk_enable(&clk); + if (ret) + return ret; + } + + clk_rate = clk_get_rate(&clk); + if (!clk_rate) + return -EINVAL; + + priv->usart_clk_rate = clk_rate; + + clk_free(&clk); + + return 0; +} + static int atmel_serial_probe(struct udevice *dev) { struct atmel_serial_platdata *plat = dev->platdata; struct atmel_serial_priv *priv = dev_get_priv(dev); + int ret; #if CONFIG_IS_ENABLED(OF_CONTROL) fdt_addr_t addr_base; @@ -202,14 +262,26 @@ static int atmel_serial_probe(struct udevice *dev) plat->base_addr = (uint32_t)addr_base; #endif priv->usart = (atmel_usart3_t *)plat->base_addr; - atmel_serial_init_internal(priv->usart); + + ret = atmel_serial_enable_clk(dev); + if (ret) + return ret; + + _atmel_serial_init(priv->usart, priv->usart_clk_rate, gd->baudrate); return 0; } #if CONFIG_IS_ENABLED(OF_CONTROL) static const struct udevice_id atmel_serial_ids[] = { - { .compatible = "atmel,at91sam9260-usart" }, + { + .compatible = "atmel,at91sam9260-dbgu", + .data = CLK_TYPE_DBGU, + }, + { + .compatible = "atmel,at91sam9260-usart", + .data = CLK_TYPE_NORMAL, + }, { } }; #endif @@ -233,7 +305,7 @@ static inline void _debug_uart_init(void) { atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_DEBUG_UART_BASE; - atmel_serial_setbrg_internal(usart, 0, CONFIG_BAUDRATE); + _atmel_serial_init(usart, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE); } static inline void _debug_uart_putc(int ch) |