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authorPatrice Chotard <patrice.chotard@st.com>2018-01-12 09:23:49 +0100
committerTom Rini <trini@konsulko.com>2018-01-19 15:49:32 -0500
commitae74de0dfd4543a18cf1aee68eb1daeb9c125fde (patch)
treeab90252b68c4648e11c80766ef950947e879fa2e /drivers/serial/serial_stm32.c
parente6e5ecc5e233911081ac8b548132f73687ae45ab (diff)
serial: stm32: Rename serial_stm32x7.c to serial_stm32.c
Now this driver is used across stm32f4, stm32f7 and stm32h7 SoCs family, give it a generic name. Signed-off-by: Patrice Chotard <patrice.chotard@st.com> Reviewed-by: Vikas Manocha <vikas.manocha@st.com>
Diffstat (limited to 'drivers/serial/serial_stm32.c')
-rw-r--r--drivers/serial/serial_stm32.c159
1 files changed, 159 insertions, 0 deletions
diff --git a/drivers/serial/serial_stm32.c b/drivers/serial/serial_stm32.c
new file mode 100644
index 0000000000..286b954fdd
--- /dev/null
+++ b/drivers/serial/serial_stm32.c
@@ -0,0 +1,159 @@
+/*
+ * 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"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+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;
+
+ int_div = DIV_ROUND_CLOSEST(plat->clock_rate, baudrate);
+
+ 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);
+ }
+
+ mantissa = (int_div / oversampling) << USART_BRR_M_SHIFT;
+ fraction = int_div % oversampling;
+
+ writel(mantissa | fraction, base + BRR_OFFSET(stm32f4));
+
+ return 0;
+}
+
+static int stm32_serial_getc(struct udevice *dev)
+{
+ 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_putc(struct udevice *dev, const char c)
+{
+ 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_TXE) == 0)
+ return -EAGAIN;
+
+ writel(c, base + TDR_OFFSET(stm32f4));
+
+ return 0;
+}
+
+static int stm32_serial_pending(struct udevice *dev, bool input)
+{
+ 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 int stm32_serial_probe(struct udevice *dev)
+{
+ 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;
+ }
+
+ 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));
+
+ return 0;
+}
+
+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},
+ {}
+};
+
+static int stm32_serial_ofdata_to_platdata(struct udevice *dev)
+{
+ struct stm32x7_serial_platdata *plat = dev_get_platdata(dev);
+
+ 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,
+};