]> git.sur5r.net Git - u-boot/commitdiff
arm: add uart dcc support
authorJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Sun, 22 Feb 2009 14:49:28 +0000 (15:49 +0100)
committerJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Sun, 22 Feb 2009 14:49:28 +0000 (15:49 +0100)
Serial driver via the EmbeddedICE macrocell's DCC channel using
co-processor 14.

It does include a timeout to ensure that the system does not
totally freeze when there is nothing connected to read.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
common/devices.c
drivers/serial/Makefile
drivers/serial/arm_dcc.c [new file with mode: 0644]
include/devices.h
lib_arm/board.c

index 38f1bbc6ae9676693daa8752ae676557d17ebdec..ba53c9bbec4cc1e627749b6f2ce9ad1efe01ab6c 100644 (file)
@@ -215,6 +215,9 @@ int devices_init (void)
        /* Initialize the list */
        INIT_LIST_HEAD(&(devs.list));
 
+#ifdef CONFIG_ARM_DCC_MULTI
+       drv_arm_dcc_init ();
+#endif
 #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C)
        i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
 #endif
index 0f980ab0a885b76d42914decfad88d7f1a2907b8..d0efd73c5bbca3d257ac950a3ab2046e86105ede 100644 (file)
@@ -25,6 +25,7 @@ include $(TOPDIR)/config.mk
 
 LIB    := $(obj)libserial.a
 
+COBJS-$(CONFIG_ARM_DCC) += arm_dcc.o
 COBJS-$(CONFIG_ATMEL_USART) += atmel_usart.o
 COBJS-$(CONFIG_MCFUART) += mcfuart.o
 COBJS-$(CONFIG_NS9750_UART) += ns9750_serial.o
diff --git a/drivers/serial/arm_dcc.c b/drivers/serial/arm_dcc.c
new file mode 100644 (file)
index 0000000..5a7fb6b
--- /dev/null
@@ -0,0 +1,226 @@
+/*
+ * Copyright (C) 2004-2007 ARM Limited.
+ * Copyright (C) 2008 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * As a special exception, if other files instantiate templates or use macros
+ * or inline functions from this file, or you compile this file and link it
+ * with other works to produce a work based on this file, this file does not
+ * by itself cause the resulting work to be covered by the GNU General Public
+ * License. However the source code for this file must still be made available
+ * in accordance with section (3) of the GNU General Public License.
+
+ * This exception does not invalidate any other reasons why a work based on
+ * this file might be covered by the GNU General Public License.
+ */
+
+#include <common.h>
+#include <devices.h>
+
+#define DCC_ARM9_RBIT  (1 << 0)
+#define DCC_ARM9_WBIT  (1 << 1)
+#define DCC_ARM11_RBIT (1 << 30)
+#define DCC_ARM11_WBIT (1 << 29)
+
+#define read_core_id(x)        do {                                            \
+               __asm__ ("mrc p15, 0, %0, c0, c0, 0\n" : "=r" (x));     \
+               x = (x >> 4) & 0xFFF;                                   \
+               } while (0);
+
+/*
+ * ARM9
+ */
+#define write_arm9_dcc(x)      \
+               __asm__ volatile ("mcr p14, 0, %0, c1, c0, 0\n" : : "r" (x))
+
+#define read_arm9_dcc(x)       \
+               __asm__ volatile ("mrc p14, 0, %0, c1, c0, 0\n" : "=r" (x))
+
+#define status_arm9_dcc(x)     \
+               __asm__ volatile ("mrc p14, 0, %0, c0, c0, 0\n" : "=r" (x))
+
+#define can_read_arm9_dcc(x)   do {    \
+               status_arm9_dcc(x);     \
+               x &= DCC_ARM9_RBIT;     \
+               } while (0);
+
+#define can_write_arm9_dcc(x)  do {    \
+               status_arm9_dcc(x);     \
+               x &= DCC_ARM9_WBIT;     \
+               x = (x == 0);           \
+               } while (0);
+
+/*
+ * ARM11
+ */
+#define write_arm11_dcc(x)     \
+               __asm__ volatile ("mcr p14, 0, %0, c0, c5, 0\n" : : "r" (x))
+
+#define read_arm11_dcc(x)      \
+               __asm__ volatile ("mrc p14, 0, %0, c0, c5, 0\n" : "=r" (x))
+
+#define status_arm11_dcc(x)    \
+               __asm__ volatile ("mrc p14, 0, %0, c0, c1, 0\n" : "=r" (x))
+
+#define can_read_arm11_dcc(x)  do {    \
+               status_arm11_dcc(x);    \
+               x &= DCC_ARM11_RBIT;    \
+               } while (0);
+
+#define can_write_arm11_dcc(x) do {    \
+               status_arm11_dcc(x);    \
+               x &= DCC_ARM11_WBIT;    \
+               x = (x == 0);           \
+               } while (0);
+
+#define TIMEOUT_COUNT 0x4000000
+
+static enum {
+       arm9_and_earlier,
+       arm11_and_later
+} arm_type = arm9_and_earlier;
+
+#ifndef CONFIG_ARM_DCC_MULTI
+#define arm_dcc_init serial_init
+void serial_setbrg(void) {}
+#define arm_dcc_getc serial_getc
+#define arm_dcc_putc serial_putc
+#define arm_dcc_puts serial_puts
+#define arm_dcc_tstc serial_tstc
+#endif
+
+int arm_dcc_init(void)
+{
+       register unsigned int id;
+
+       read_core_id(id);
+
+       if (id >= 0xb00)
+               arm_type = arm11_and_later;
+       else
+               arm_type = arm9_and_earlier;
+
+       return 0;
+}
+
+int arm_dcc_getc(void)
+{
+       int ch;
+       register unsigned int reg;
+
+       switch (arm_type) {
+       case arm11_and_later:
+               do {
+                       can_read_arm11_dcc(reg);
+               } while (!reg);
+               read_arm11_dcc(ch);
+               break;
+
+       case arm9_and_earlier:
+       default:
+               do {
+                       can_read_arm9_dcc(reg);
+               } while (!reg);
+               read_arm9_dcc(ch);
+               break;
+       }
+
+       return ch;
+}
+
+void arm_dcc_putc(char ch)
+{
+       register unsigned int reg;
+       unsigned int timeout_count = TIMEOUT_COUNT;
+
+       switch (arm_type) {
+       case arm11_and_later:
+               while (--timeout_count) {
+                       can_write_arm11_dcc(reg);
+                       if (reg)
+                               break;
+               }
+               if (timeout_count == 0)
+                       return;
+               else
+                       write_arm11_dcc(ch);
+               break;
+
+       case arm9_and_earlier:
+       default:
+               while (--timeout_count) {
+                       can_write_arm9_dcc(reg);
+                       if (reg)
+                               break;
+               }
+               if (timeout_count == 0)
+                       return;
+               else
+                       write_arm9_dcc(ch);
+               break;
+       }
+}
+
+void arm_dcc_puts(const char *s)
+{
+       while (*s)
+               arm_dcc_putc(*s++);
+}
+
+int arm_dcc_tstc(void)
+{
+       register unsigned int reg;
+
+       switch (arm_type) {
+       case arm11_and_later:
+               can_read_arm11_dcc(reg);
+               break;
+       case arm9_and_earlier:
+       default:
+               can_read_arm9_dcc(reg);
+               break;
+       }
+
+       return reg;
+}
+
+#ifdef CONFIG_ARM_DCC_MULTI
+static device_t arm_dcc_dev;
+
+int drv_arm_dcc_init(void)
+{
+       int rc;
+
+       /* Device initialization */
+       memset(&arm_dcc_dev, 0, sizeof(arm_dcc_dev));
+
+       strcpy(arm_dcc_dev.name, "dcc");
+       arm_dcc_dev.ext = 0;    /* No extensions */
+       arm_dcc_dev.flags = DEV_FLAGS_INPUT | DEV_FLAGS_OUTPUT;
+       arm_dcc_dev.tstc = arm_dcc_tstc;        /* 'tstc' function */
+       arm_dcc_dev.getc = arm_dcc_getc;        /* 'getc' function */
+       arm_dcc_dev.putc = arm_dcc_putc;        /* 'putc' function */
+       arm_dcc_dev.puts = arm_dcc_puts;        /* 'puts' function */
+
+       rc = device_register(&arm_dcc_dev);
+
+       if (rc == 0) {
+               arm_dcc_init();
+               return 1;
+       }
+
+       return 0;
+}
+#endif
index 84c4514880eb02c98ded2b6726f340db4a60dd6a..3a9881bf0498c8ed1acc13fe6ad1bb1d4545a236 100644 (file)
@@ -98,6 +98,9 @@ struct list_head* device_get_list(void);
 device_t* device_get_by_name(char* name);
 device_t* device_clone(device_t *dev);
 
+#ifdef CONFIG_ARM_DCC_MULTI
+int drv_arm_dcc_init(void);
+#endif
 #ifdef CONFIG_LCD
 int    drv_lcd_init (void);
 #endif
index f125d38b0b6c51c228cd154323ec26a7be86d690..09eaaf25c4104d0ebdd4baedde1f8841ea4c730c 100644 (file)
@@ -145,6 +145,9 @@ void inline yellow_LED_off(void)__attribute__((weak, alias("__yellow_LED_off")))
  * but let's get it working (again) first...
  */
 
+#if defined(CONFIG_ARM_DCC) && !defined(CONFIG_BAUDRATE)
+#define CONFIG_BAUDRATE 115200
+#endif
 static int init_baudrate (void)
 {
        char tmp[64];   /* long enough for environment variables */