Merge tag 'xilinx-for-v2018.03' of git://git.denx.de/u-boot-microblaze
[oweals/u-boot.git] / drivers / serial / serial_stm32.c
index 3c800961d1affb49bb23154e877ea4e4efb0dfca..286b954fdd74cfb98a93d573a1de1fca374aa90b 100644 (file)
 /*
- * (C) Copyright 2015
- * Kamil Lulko, <rev13@wp.pl>
+ * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
+ * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
  *
  * SPDX-License-Identifier:    GPL-2.0+
  */
 
 #include <common.h>
+#include <clk.h>
+#include <dm.h>
 #include <asm/io.h>
 #include <serial.h>
 #include <asm/arch/stm32.h>
+#include "serial_stm32.h"
 
-#define STM32_USART1_BASE      (STM32_APB2PERIPH_BASE + 0x1000)
-#define RCC_APB2ENR_USART1EN   (1 << 4)
+DECLARE_GLOBAL_DATA_PTR;
 
-#define USART_BASE             STM32_USART1_BASE
-#define RCC_USART_ENABLE       RCC_APB2ENR_USART1EN
+static int stm32_serial_setbrg(struct udevice *dev, int baudrate)
+{
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+       bool stm32f4 = plat->uart_info->stm32f4;
+       fdt_addr_t base = plat->base;
+       u32 int_div, mantissa, fraction, oversampling;
 
-struct stm32_serial {
-       u32 sr;
-       u32 dr;
-       u32 brr;
-       u32 cr1;
-       u32 cr2;
-       u32 cr3;
-       u32 gtpr;
-};
+       int_div = DIV_ROUND_CLOSEST(plat->clock_rate, baudrate);
 
-#define USART_CR1_RE           (1 << 2)
-#define USART_CR1_TE           (1 << 3)
-#define USART_CR1_UE           (1 << 13)
+       if (int_div < 16) {
+               oversampling = 8;
+               setbits_le32(base + CR1_OFFSET(stm32f4), USART_CR1_OVER8);
+       } else {
+               oversampling = 16;
+               clrbits_le32(base + CR1_OFFSET(stm32f4), USART_CR1_OVER8);
+       }
 
-#define USART_SR_FLAG_RXNE     (1 << 5)
-#define USART_SR_FLAG_TXE      (1 << 7)
+       mantissa = (int_div / oversampling) << USART_BRR_M_SHIFT;
+       fraction = int_div % oversampling;
 
-#define USART_BRR_F_MASK       0xF
-#define USART_BRR_M_SHIFT      4
-#define USART_BRR_M_MASK       0xFFF0
+       writel(mantissa | fraction, base + BRR_OFFSET(stm32f4));
 
-DECLARE_GLOBAL_DATA_PTR;
+       return 0;
+}
 
-static void stm32_serial_setbrg(void)
+static int stm32_serial_getc(struct udevice *dev)
 {
-       serial_init();
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+       bool stm32f4 = plat->uart_info->stm32f4;
+       fdt_addr_t base = plat->base;
+
+       if ((readl(base + ISR_OFFSET(stm32f4)) & USART_SR_FLAG_RXNE) == 0)
+               return -EAGAIN;
+
+       return readl(base + RDR_OFFSET(stm32f4));
 }
 
-static int stm32_serial_init(void)
+static int stm32_serial_putc(struct udevice *dev, const char c)
 {
-       struct stm32_serial *usart = (struct stm32_serial *)USART_BASE;
-       u32 clock, int_div, frac_div, tmp;
-
-       if ((USART_BASE & STM32_BUS_MASK) == STM32_APB1PERIPH_BASE) {
-               setbits_le32(&STM32_RCC->apb1enr, RCC_USART_ENABLE);
-               clock = clock_get(CLOCK_APB1);
-       } else if ((USART_BASE & STM32_BUS_MASK) == STM32_APB2PERIPH_BASE) {
-               setbits_le32(&STM32_RCC->apb2enr, RCC_USART_ENABLE);
-               clock = clock_get(CLOCK_APB2);
-       } else {
-               return -1;
-       }
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+       bool stm32f4 = plat->uart_info->stm32f4;
+       fdt_addr_t base = plat->base;
 
-       int_div = (25 * clock) / (4 * gd->baudrate);
-       tmp = ((int_div / 100) << USART_BRR_M_SHIFT) & USART_BRR_M_MASK;
-       frac_div = int_div - (100 * (tmp >> USART_BRR_M_SHIFT));
-       tmp |= (((frac_div * 16) + 50) / 100) & USART_BRR_F_MASK;
+       if ((readl(base + ISR_OFFSET(stm32f4)) & USART_SR_FLAG_TXE) == 0)
+               return -EAGAIN;
 
-       writel(tmp, &usart->brr);
-       setbits_le32(&usart->cr1, USART_CR1_RE | USART_CR1_TE | USART_CR1_UE);
+       writel(c, base + TDR_OFFSET(stm32f4));
 
        return 0;
 }
 
-static int stm32_serial_getc(void)
+static int stm32_serial_pending(struct udevice *dev, bool input)
 {
-       struct stm32_serial *usart = (struct stm32_serial *)USART_BASE;
-       while ((readl(&usart->sr) & USART_SR_FLAG_RXNE) == 0)
-               ;
-       return readl(&usart->dr);
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+       bool stm32f4 = plat->uart_info->stm32f4;
+       fdt_addr_t base = plat->base;
+
+       if (input)
+               return readl(base + ISR_OFFSET(stm32f4)) &
+                       USART_SR_FLAG_RXNE ? 1 : 0;
+       else
+               return readl(base + ISR_OFFSET(stm32f4)) &
+                       USART_SR_FLAG_TXE ? 0 : 1;
 }
 
-static void stm32_serial_putc(const char c)
+static int stm32_serial_probe(struct udevice *dev)
 {
-       struct stm32_serial *usart = (struct stm32_serial *)USART_BASE;
-       while ((readl(&usart->sr) & USART_SR_FLAG_TXE) == 0)
-               ;
-       writel(c, &usart->dr);
-}
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+       struct clk clk;
+       fdt_addr_t base = plat->base;
+       int ret;
+       bool stm32f4;
+       u8 uart_enable_bit;
+
+       plat->uart_info = (struct stm32_uart_info *)dev_get_driver_data(dev);
+       stm32f4 = plat->uart_info->stm32f4;
+       uart_enable_bit = plat->uart_info->uart_enable_bit;
+
+       ret = clk_get_by_index(dev, 0, &clk);
+       if (ret < 0)
+               return ret;
+
+       ret = clk_enable(&clk);
+       if (ret) {
+               dev_err(dev, "failed to enable clock\n");
+               return ret;
+       }
 
-static int stm32_serial_tstc(void)
-{
-       struct stm32_serial *usart = (struct stm32_serial *)USART_BASE;
-       u8 ret;
+       plat->clock_rate = clk_get_rate(&clk);
+       if (plat->clock_rate < 0) {
+               clk_disable(&clk);
+               return plat->clock_rate;
+       };
+
+       /* Disable uart-> disable overrun-> enable uart */
+       clrbits_le32(base + CR1_OFFSET(stm32f4), USART_CR1_RE | USART_CR1_TE |
+                    BIT(uart_enable_bit));
+       if (plat->uart_info->has_overrun_disable)
+               setbits_le32(base + CR3_OFFSET(stm32f4), USART_CR3_OVRDIS);
+       if (plat->uart_info->has_fifo)
+               setbits_le32(base + CR1_OFFSET(stm32f4), USART_CR1_FIFOEN);
+       setbits_le32(base + CR1_OFFSET(stm32f4), USART_CR1_RE | USART_CR1_TE |
+                    BIT(uart_enable_bit));
 
-       ret = readl(&usart->sr) & USART_SR_FLAG_RXNE;
-       return ret;
+       return 0;
 }
 
-static struct serial_device stm32_serial_drv = {
-       .name   = "stm32_serial",
-       .start  = stm32_serial_init,
-       .stop   = NULL,
-       .setbrg = stm32_serial_setbrg,
-       .putc   = stm32_serial_putc,
-       .puts   = default_serial_puts,
-       .getc   = stm32_serial_getc,
-       .tstc   = stm32_serial_tstc,
+static const struct udevice_id stm32_serial_id[] = {
+       { .compatible = "st,stm32-uart", .data = (ulong)&stm32f4_info},
+       { .compatible = "st,stm32f7-uart", .data = (ulong)&stm32f7_info},
+       { .compatible = "st,stm32h7-uart", .data = (ulong)&stm32h7_info},
+       {}
 };
 
-void stm32_serial_initialize(void)
+static int stm32_serial_ofdata_to_platdata(struct udevice *dev)
 {
-       serial_register(&stm32_serial_drv);
-}
+       struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
 
-__weak struct serial_device *default_serial_console(void)
-{
-       return &stm32_serial_drv;
+       plat->base = devfdt_get_addr(dev);
+       if (plat->base == FDT_ADDR_T_NONE)
+               return -EINVAL;
+
+       return 0;
 }
+
+static const struct dm_serial_ops stm32_serial_ops = {
+       .putc = stm32_serial_putc,
+       .pending = stm32_serial_pending,
+       .getc = stm32_serial_getc,
+       .setbrg = stm32_serial_setbrg,
+};
+
+U_BOOT_DRIVER(serial_stm32) = {
+       .name = "serial_stm32",
+       .id = UCLASS_SERIAL,
+       .of_match = of_match_ptr(stm32_serial_id),
+       .ofdata_to_platdata = of_match_ptr(stm32_serial_ofdata_to_platdata),
+       .platdata_auto_alloc_size = sizeof(struct stm32x7_serial_platdata),
+       .ops = &stm32_serial_ops,
+       .probe = stm32_serial_probe,
+       .flags = DM_FLAG_PRE_RELOC,
+};