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-rw-r--r--arch/arm/cpu/arm1176/bcm2835/Makefile2
-rw-r--r--arch/arm/cpu/arm1176/bcm2835/mbox.c164
2 files changed, 165 insertions, 1 deletions
diff --git a/arch/arm/cpu/arm1176/bcm2835/Makefile b/arch/arm/cpu/arm1176/bcm2835/Makefile
index 95da6a8..135de42 100644
--- a/arch/arm/cpu/arm1176/bcm2835/Makefile
+++ b/arch/arm/cpu/arm1176/bcm2835/Makefile
@@ -17,7 +17,7 @@ include $(TOPDIR)/config.mk
LIB = $(obj)lib$(SOC).o
SOBJS := lowlevel_init.o
-COBJS := init.o reset.o timer.o
+COBJS := init.o reset.o timer.o mbox.o
SRCS := $(SOBJS:.o=.c) $(COBJS:.o=.c)
OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
diff --git a/arch/arm/cpu/arm1176/bcm2835/mbox.c b/arch/arm/cpu/arm1176/bcm2835/mbox.c
new file mode 100644
index 0000000..fd65e33
--- /dev/null
+++ b/arch/arm/cpu/arm1176/bcm2835/mbox.c
@@ -0,0 +1,164 @@
+/*
+ * (C) Copyright 2012 Stephen Warren
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/mbox.h>
+
+#define TIMEOUT (100 * 1000) /* 100mS in uS */
+
+int bcm2835_mbox_call_raw(u32 chan, u32 send, u32 *recv)
+{
+ struct bcm2835_mbox_regs *regs =
+ (struct bcm2835_mbox_regs *)BCM2835_MBOX_PHYSADDR;
+ ulong endtime = get_timer(0) + TIMEOUT;
+ u32 val;
+
+ debug("time: %lu timeout: %lu\n", get_timer(0), endtime);
+
+ if (send & BCM2835_CHAN_MASK) {
+ printf("mbox: Illegal mbox data 0x%08x\n", send);
+ return -1;
+ }
+
+ /* Drain any stale responses */
+
+ for (;;) {
+ val = readl(&regs->status);
+ if (val & BCM2835_MBOX_STATUS_RD_EMPTY)
+ break;
+ if (get_timer(0) >= endtime) {
+ printf("mbox: Timeout draining stale responses\n");
+ return -1;
+ }
+ val = readl(&regs->read);
+ }
+
+ /* Wait for space to send */
+
+ for (;;) {
+ val = readl(&regs->status);
+ if (!(val & BCM2835_MBOX_STATUS_WR_FULL))
+ break;
+ if (get_timer(0) >= endtime) {
+ printf("mbox: Timeout waiting for send space\n");
+ return -1;
+ }
+ }
+
+ /* Send the request */
+
+ val = BCM2835_MBOX_PACK(chan, send);
+ debug("mbox: TX raw: 0x%08x\n", val);
+ writel(val, &regs->write);
+
+ /* Wait for the response */
+
+ for (;;) {
+ val = readl(&regs->status);
+ if (!(val & BCM2835_MBOX_STATUS_RD_EMPTY))
+ break;
+ if (get_timer(0) >= endtime) {
+ printf("mbox: Timeout waiting for response\n");
+ return -1;
+ }
+ }
+
+ /* Read the response */
+
+ val = readl(&regs->read);
+ debug("mbox: RX raw: 0x%08x\n", val);
+
+ /* Validate the response */
+
+ if (BCM2835_MBOX_UNPACK_CHAN(val) != chan) {
+ printf("mbox: Response channel mismatch\n");
+ return -1;
+ }
+
+ *recv = BCM2835_MBOX_UNPACK_DATA(val);
+
+ return 0;
+}
+
+#ifdef DEBUG
+void dump_buf(struct bcm2835_mbox_hdr *buffer)
+{
+ u32 *p;
+ u32 words;
+ int i;
+
+ p = (u32 *)buffer;
+ words = buffer->buf_size / 4;
+ for (i = 0; i < words; i++)
+ printf(" 0x%04x: 0x%08x\n", i * 4, p[i]);
+}
+#endif
+
+int bcm2835_mbox_call_prop(u32 chan, struct bcm2835_mbox_hdr *buffer)
+{
+ int ret;
+ u32 rbuffer;
+ struct bcm2835_mbox_tag_hdr *tag;
+ int tag_index;
+
+#ifdef DEBUG
+ printf("mbox: TX buffer\n");
+ dump_buf(buffer);
+#endif
+
+ ret = bcm2835_mbox_call_raw(chan, (u32)buffer, &rbuffer);
+ if (ret)
+ return ret;
+ if (rbuffer != (u32)buffer) {
+ printf("mbox: Response buffer mismatch\n");
+ return -1;
+ }
+
+#ifdef DEBUG
+ printf("mbox: RX buffer\n");
+ dump_buf(buffer);
+#endif
+
+ /* Validate overall response status */
+
+ if (buffer->code != BCM2835_MBOX_RESP_CODE_SUCCESS) {
+ printf("mbox: Header response code invalid\n");
+ return -1;
+ }
+
+ /* Validate each tag's response status */
+
+ tag = (void *)(buffer + 1);
+ tag_index = 0;
+ while (tag->tag) {
+ if (!(tag->val_len & BCM2835_MBOX_TAG_VAL_LEN_RESPONSE)) {
+ printf("mbox: Tag %d missing val_len response bit\n",
+ tag_index);
+ return -1;
+ }
+ /*
+ * Clear the reponse bit so clients can just look right at the
+ * length field without extra processing
+ */
+ tag->val_len &= ~BCM2835_MBOX_TAG_VAL_LEN_RESPONSE;
+ tag = (void *)(((u8 *)tag) + sizeof(*tag) + tag->val_buf_size);
+ tag_index++;
+ }
+
+ return 0;
+}