[U-Boot] [PATCH] ARM: rpi_b: power on SDHCI and USB HW modules

Stephen Warren swarren at wwwdotorg.org
Tue Nov 26 05:24:14 CET 2013


Send RPC commands to the VideoCore to turn on the SDHCI and USB modules.
For SDHCI this isn't needed in practice, since the firmware already
turned on the power in order to load U-Boot. However, it's best to be
explicit. For USB, this is necessary, since the module isn't powered
otherwise. This will allow the kernel USB driver to work.

Signed-off-by: Stephen Warren <swarren at wwwdotorg.org>
---
 arch/arm/include/asm/arch-bcm2835/mbox.h |   48 ++++++++++++++++++++++++++++++
 board/raspberrypi/rpi_b/rpi_b.c          |   34 ++++++++++++++++++++-
 2 files changed, 81 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/arch-bcm2835/mbox.h b/arch/arm/include/asm/arch-bcm2835/mbox.h
index 6b806ec..38cb42a 100644
--- a/arch/arm/include/asm/arch-bcm2835/mbox.h
+++ b/arch/arm/include/asm/arch-bcm2835/mbox.h
@@ -133,6 +133,54 @@ struct bcm2835_mbox_tag_get_arm_mem {
 	} body;
 };
 
+#define BCM2835_MBOX_POWER_DEVID_SDHCI		0
+#define BCM2835_MBOX_POWER_DEVID_UART0		1
+#define BCM2835_MBOX_POWER_DEVID_UART1		2
+#define BCM2835_MBOX_POWER_DEVID_USB_HCD	3
+#define BCM2835_MBOX_POWER_DEVID_I2C0		4
+#define BCM2835_MBOX_POWER_DEVID_I2C1		5
+#define BCM2835_MBOX_POWER_DEVID_I2C2		6
+#define BCM2835_MBOX_POWER_DEVID_SPI		7
+#define BCM2835_MBOX_POWER_DEVID_CCP2TX		8
+
+#define BCM2835_MBOX_POWER_STATE_RESP_ON	(1 << 1)
+/* Device doesn't exist */
+#define BCM2835_MBOX_POWER_STATE_RESP_NODEV	(1 << 1)
+
+#define BCM2835_MBOX_TAG_GET_POWER_STATE	0x00020001
+
+struct bcm2835_mbox_tag_get_power_state {
+	struct bcm2835_mbox_tag_hdr tag_hdr;
+	union {
+		struct {
+			u32 device_id;
+		} req;
+		struct {
+			u32 device_id;
+			u32 state;
+		} resp;
+	} body;
+};
+
+#define BCM2835_MBOX_TAG_SET_POWER_STATE	0x00028001
+
+#define BCM2835_MBOX_SET_POWER_STATE_REQ_ON	(1 << 0)
+#define BCM2835_MBOX_SET_POWER_STATE_REQ_WAIT	(1 << 1)
+
+struct bcm2835_mbox_tag_set_power_state {
+	struct bcm2835_mbox_tag_hdr tag_hdr;
+	union {
+		struct {
+			u32 device_id;
+			u32 state;
+		} req;
+		struct {
+			u32 device_id;
+			u32 state;
+		} resp;
+	} body;
+};
+
 #define BCM2835_MBOX_TAG_GET_CLOCK_RATE	0x00030002
 
 #define BCM2835_MBOX_CLOCK_ID_EMMC	1
diff --git a/board/raspberrypi/rpi_b/rpi_b.c b/board/raspberrypi/rpi_b/rpi_b.c
index 16d442a..f33fae9 100644
--- a/board/raspberrypi/rpi_b/rpi_b.c
+++ b/board/raspberrypi/rpi_b/rpi_b.c
@@ -29,6 +29,12 @@ struct msg_get_arm_mem {
 	u32 end_tag;
 };
 
+struct msg_set_power_state {
+	struct bcm2835_mbox_hdr hdr;
+	struct bcm2835_mbox_tag_set_power_state set_power_state;
+	u32 end_tag;
+};
+
 struct msg_get_clock_rate {
 	struct bcm2835_mbox_hdr hdr;
 	struct bcm2835_mbox_tag_get_clock_rate get_clock_rate;
@@ -54,11 +60,35 @@ int dram_init(void)
 	return 0;
 }
 
+static int power_on_module(u32 module)
+{
+	ALLOC_ALIGN_BUFFER(struct msg_set_power_state, msg_pwr, 1, 16);
+	int ret;
+
+	BCM2835_MBOX_INIT_HDR(msg_pwr);
+	BCM2835_MBOX_INIT_TAG(&msg_pwr->set_power_state,
+			      SET_POWER_STATE);
+	msg_pwr->set_power_state.body.req.device_id = module;
+	msg_pwr->set_power_state.body.req.state =
+		BCM2835_MBOX_SET_POWER_STATE_REQ_ON |
+		BCM2835_MBOX_SET_POWER_STATE_REQ_WAIT;
+
+	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN,
+				     &msg_pwr->hdr);
+	if (ret) {
+		printf("bcm2835: Could not set module %u power state\n",
+		       module);
+		return -1;
+	}
+
+	return 0;
+}
+
 int board_init(void)
 {
 	gd->bd->bi_boot_params = 0x100;
 
-	return 0;
+	return power_on_module(BCM2835_MBOX_POWER_DEVID_USB_HCD);
 }
 
 int board_mmc_init(void)
@@ -66,6 +96,8 @@ int board_mmc_init(void)
 	ALLOC_ALIGN_BUFFER(struct msg_get_clock_rate, msg_clk, 1, 16);
 	int ret;
 
+	power_on_module(BCM2835_MBOX_POWER_DEVID_SDHCI);
+
 	BCM2835_MBOX_INIT_HDR(msg_clk);
 	BCM2835_MBOX_INIT_TAG(&msg_clk->get_clock_rate, GET_CLOCK_RATE);
 	msg_clk->get_clock_rate.body.req.clock_id = BCM2835_MBOX_CLOCK_ID_EMMC;
-- 
1.7.10.4



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