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Diffstat (limited to 'drivers/rpi3/mailbox/rpi3_mbox.c')
-rw-r--r--drivers/rpi3/mailbox/rpi3_mbox.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/rpi3/mailbox/rpi3_mbox.c b/drivers/rpi3/mailbox/rpi3_mbox.c
new file mode 100644
index 0000000..aef1f39
--- /dev/null
+++ b/drivers/rpi3/mailbox/rpi3_mbox.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <platform_def.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <lib/mmio.h>
+
+#include <rpi_hw.h>
+
+#include <drivers/rpi3/mailbox/rpi3_mbox.h>
+
+#define RPI3_MAILBOX_MAX_RETRIES U(1000000)
+
+/*******************************************************************************
+ * Routine to send requests to the VideoCore using the mailboxes.
+ ******************************************************************************/
+void rpi3_vc_mailbox_request_send(rpi3_mbox_request_t *req, int req_size)
+{
+ uint32_t st, data;
+ uintptr_t resp_addr, addr;
+ unsigned int retries;
+
+ /* This is the location of the request buffer */
+ addr = (uintptr_t)req;
+
+ /* Make sure that the changes are seen by the VideoCore */
+ flush_dcache_range(addr, req_size);
+
+ /* Wait until the outbound mailbox is empty */
+ retries = 0U;
+
+ do {
+ st = mmio_read_32(RPI3_MBOX_BASE + RPI3_MBOX1_STATUS_OFFSET);
+
+ retries++;
+ if (retries == RPI3_MAILBOX_MAX_RETRIES) {
+ ERROR("rpi3: mbox: Send request timeout\n");
+ return;
+ }
+
+ } while ((st & RPI3_MBOX_STATUS_EMPTY_MASK) == 0U);
+
+ /* Send base address of this message to start request */
+ mmio_write_32(RPI3_MBOX_BASE + RPI3_MBOX1_WRITE_OFFSET,
+ RPI3_CHANNEL_ARM_TO_VC | (uint32_t) addr);
+
+ /* Wait until the inbound mailbox isn't empty */
+ retries = 0U;
+
+ do {
+ st = mmio_read_32(RPI3_MBOX_BASE + RPI3_MBOX0_STATUS_OFFSET);
+
+ retries++;
+ if (retries == RPI3_MAILBOX_MAX_RETRIES) {
+ ERROR("rpi3: mbox: Receive response timeout\n");
+ return;
+ }
+
+ } while ((st & RPI3_MBOX_STATUS_EMPTY_MASK) != 0U);
+
+ /* Get location and channel */
+ data = mmio_read_32(RPI3_MBOX_BASE + RPI3_MBOX0_READ_OFFSET);
+
+ if ((data & RPI3_CHANNEL_MASK) != RPI3_CHANNEL_ARM_TO_VC) {
+ ERROR("rpi3: mbox: Wrong channel: 0x%08x\n", data);
+ panic();
+ }
+
+ resp_addr = (uintptr_t)(data & ~RPI3_CHANNEL_MASK);
+ if (addr != resp_addr) {
+ ERROR("rpi3: mbox: Unexpected address: 0x%08x\n", data);
+ panic();
+ }
+
+ /* Make sure that the data seen by the CPU is up to date */
+ inv_dcache_range(addr, req_size);
+}