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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/drivers/serial/atmel_usart.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/drivers/serial/atmel_usart.c')
-rw-r--r--qemu/roms/u-boot/drivers/serial/atmel_usart.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/drivers/serial/atmel_usart.c b/qemu/roms/u-boot/drivers/serial/atmel_usart.c
new file mode 100644
index 000000000..8f0e3489a
--- /dev/null
+++ b/qemu/roms/u-boot/drivers/serial/atmel_usart.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * Modified to support C structur SoC access by
+ * Andreas Bießmann <biessmann@corscience.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+#include <common.h>
+#include <watchdog.h>
+#include <serial.h>
+#include <linux/compiler.h>
+
+#include <asm/io.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/hardware.h>
+
+#include "atmel_usart.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static void atmel_serial_setbrg(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
+ unsigned long divisor;
+ unsigned long usart_hz;
+
+ /*
+ * Master Clock
+ * Baud Rate = --------------
+ * 16 * CD
+ */
+ usart_hz = get_usart_clk_rate(CONFIG_USART_ID);
+ divisor = (usart_hz / 16 + gd->baudrate / 2) / gd->baudrate;
+ writel(USART3_BF(CD, divisor), &usart->brgr);
+}
+
+static int atmel_serial_init(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
+
+ /*
+ * Just in case: drain transmitter register
+ * 1000us is enough for baudrate >= 9600
+ */
+ if (!(readl(&usart->csr) & USART3_BIT(TXEMPTY)))
+ __udelay(1000);
+
+ writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr);
+
+ serial_setbrg();
+
+ 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);
+ writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr);
+ /* 100us is enough for the new settings to be settled */
+ __udelay(100);
+
+ return 0;
+}
+
+static void atmel_serial_putc(char c)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
+
+ if (c == '\n')
+ serial_putc('\r');
+
+ while (!(readl(&usart->csr) & USART3_BIT(TXRDY)));
+ writel(c, &usart->thr);
+}
+
+static int atmel_serial_getc(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
+
+ while (!(readl(&usart->csr) & USART3_BIT(RXRDY)))
+ WATCHDOG_RESET();
+ return readl(&usart->rhr);
+}
+
+static int atmel_serial_tstc(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
+ return (readl(&usart->csr) & USART3_BIT(RXRDY)) != 0;
+}
+
+static struct serial_device atmel_serial_drv = {
+ .name = "atmel_serial",
+ .start = atmel_serial_init,
+ .stop = NULL,
+ .setbrg = atmel_serial_setbrg,
+ .putc = atmel_serial_putc,
+ .puts = default_serial_puts,
+ .getc = atmel_serial_getc,
+ .tstc = atmel_serial_tstc,
+};
+
+void atmel_serial_initialize(void)
+{
+ serial_register(&atmel_serial_drv);
+}
+
+__weak struct serial_device *default_serial_console(void)
+{
+ return &atmel_serial_drv;
+}