[PATCH U-Boot] ARM: rpi_b: detect board revision
Stephen Warren
swarren at wwwdotorg.org
Tue Nov 18 20:40:21 PST 2014
Detect the board revision early during boot, and print the decoded
model name.
Eventually, this information can be used for tasks such as:
- Allowing/preventing USB device mode; some models have a USB device on-
board so only host mode makes sense. Others connect the SoC directly
to the USB connector, so device-mode might make sense.
- The on-board USB hub/Ethernet requires different GPIOs to enable it,
although luckily the default appears to be fine so far.
- The compute module contains an on-board eMMC device, so we could store
the environment there. Other models use an SD card and so don't support
saving the environment (unless we store it in a file on the FAT boot
partition...)
Set $fdtfile based on this information. At present, the mainline Linux
kernel doesn't contain a separate DTB for most models, but I hope that
will change soon.
Signed-off-by: Stephen Warren <swarren at wwwdotorg.org>
---
I'm considering renaming rpi_b -> rpi in U-Boot since it supports many
models. Hopefully I can persuade U-Boot to load the environment from
different places at run-time, so we won't need different builds based
on whether the environment is in eMMC or not for example.
arch/arm/include/asm/arch-bcm2835/mbox.h | 33 +++++++++
board/raspberrypi/rpi_b/rpi_b.c | 122 ++++++++++++++++++++++++++++++-
include/configs/rpi_b.h | 1 -
3 files changed, 152 insertions(+), 4 deletions(-)
diff --git a/arch/arm/include/asm/arch-bcm2835/mbox.h b/arch/arm/include/asm/arch-bcm2835/mbox.h
index 61f427d914cd..0289ba6a917e 100644
--- a/arch/arm/include/asm/arch-bcm2835/mbox.h
+++ b/arch/arm/include/asm/arch-bcm2835/mbox.h
@@ -119,6 +119,39 @@ struct bcm2835_mbox_tag_hdr {
* };
*/
+#define BCM2835_MBOX_TAG_GET_BOARD_REV 0x00010002
+
+/*
+ * 0x2..0xf from:
+ * http://raspberryalphaomega.org.uk/2013/02/06/automatic-raspberry-pi-board-revision-detection-model-a-b1-and-b2/
+ * http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=32733
+ * 0x10, 0x11 from swarren's testing
+ */
+#define BCM2835_BOARD_REV_B_I2C0_2 0x2
+#define BCM2835_BOARD_REV_B_I2C0_3 0x3
+#define BCM2835_BOARD_REV_B_I2C1_4 0x4
+#define BCM2835_BOARD_REV_B_I2C1_5 0x5
+#define BCM2835_BOARD_REV_B_I2C1_6 0x6
+#define BCM2835_BOARD_REV_A_7 0x7
+#define BCM2835_BOARD_REV_A_8 0x8
+#define BCM2835_BOARD_REV_A_9 0x9
+#define BCM2835_BOARD_REV_B_REV2_d 0xd
+#define BCM2835_BOARD_REV_B_REV2_e 0xe
+#define BCM2835_BOARD_REV_B_REV2_f 0xf
+#define BCM2835_BOARD_REV_B_PLUS 0x10
+#define BCM2835_BOARD_REV_CM 0x11
+
+struct bcm2835_mbox_tag_get_board_rev {
+ struct bcm2835_mbox_tag_hdr tag_hdr;
+ union {
+ struct {
+ } req;
+ struct {
+ u32 rev;
+ } resp;
+ } body;
+};
+
#define BCM2835_MBOX_TAG_GET_MAC_ADDRESS 0x00010003
struct bcm2835_mbox_tag_get_mac_address {
diff --git a/board/raspberrypi/rpi_b/rpi_b.c b/board/raspberrypi/rpi_b/rpi_b.c
index 7445f5318ad2..aaded88b4ba0 100644
--- a/board/raspberrypi/rpi_b/rpi_b.c
+++ b/board/raspberrypi/rpi_b/rpi_b.c
@@ -42,6 +42,12 @@ struct msg_get_arm_mem {
u32 end_tag;
};
+struct msg_get_board_rev {
+ struct bcm2835_mbox_hdr hdr;
+ struct bcm2835_mbox_tag_get_board_rev get_board_rev;
+ u32 end_tag;
+};
+
struct msg_get_mac_address {
struct bcm2835_mbox_hdr hdr;
struct bcm2835_mbox_tag_get_mac_address get_mac_address;
@@ -60,6 +66,67 @@ struct msg_get_clock_rate {
u32 end_tag;
};
+/* See comments in mbox.h for data source */
+static const struct {
+ const char *name;
+ const char *fdtfile;
+} models[] = {
+ [BCM2835_BOARD_REV_B_I2C0_2] = {
+ "Model B (no P5)",
+ "bcm2835-rpi-b-i2c0.dtb",
+ },
+ [BCM2835_BOARD_REV_B_I2C0_3] = {
+ "Model B (no P5)",
+ "bcm2835-rpi-b-i2c0.dtb",
+ },
+ [BCM2835_BOARD_REV_B_I2C1_4] = {
+ "Model B",
+ "bcm2835-rpi-b.dtb",
+ },
+ [BCM2835_BOARD_REV_B_I2C1_5] = {
+ "Model B",
+ "bcm2835-rpi-b.dtb",
+ },
+ [BCM2835_BOARD_REV_B_I2C1_6] = {
+ "Model B",
+ "bcm2835-rpi-b.dtb",
+ },
+ [BCM2835_BOARD_REV_A_7] = {
+ "Model A",
+ "bcm2835-rpi-a.dtb",
+ },
+ [BCM2835_BOARD_REV_A_8] = {
+ "Model A",
+ "bcm2835-rpi-a.dtb",
+ },
+ [BCM2835_BOARD_REV_A_9] = {
+ "Model A",
+ "bcm2835-rpi-a.dtb",
+ },
+ [BCM2835_BOARD_REV_B_REV2_d] = {
+ "Model B rev2",
+ "bcm2835-rpi-b-rev2.dtb",
+ },
+ [BCM2835_BOARD_REV_B_REV2_e] = {
+ "Model B rev2",
+ "bcm2835-rpi-b-rev2.dtb",
+ },
+ [BCM2835_BOARD_REV_B_REV2_f] = {
+ "Model B rev2",
+ "bcm2835-rpi-b-rev2.dtb",
+ },
+ [BCM2835_BOARD_REV_B_PLUS] = {
+ "Model B+",
+ "bcm2835-rpi-b-plus.dtb",
+ },
+ [BCM2835_BOARD_REV_CM] = {
+ "Compute Module",
+ "bcm2835-rpi-cm.dtb",
+ },
+};
+
+u32 rpi_board_rev = 0;
+
int dram_init(void)
{
ALLOC_ALIGN_BUFFER(struct msg_get_arm_mem, msg, 1, 16);
@@ -79,13 +146,27 @@ int dram_init(void)
return 0;
}
-int misc_init_r(void)
+static void set_fdtfile(void)
+{
+ const char *fdtfile;
+
+ if (getenv("fdtfile"))
+ return;
+
+ fdtfile = models[rpi_board_rev].fdtfile;
+ if (!fdtfile)
+ fdtfile = "bcm2835-rpi-other.dtb";
+
+ setenv("fdtfile", fdtfile);
+}
+
+static void set_usbethaddr(void)
{
ALLOC_ALIGN_BUFFER(struct msg_get_mac_address, msg, 1, 16);
int ret;
if (getenv("usbethaddr"))
- return 0;
+ return;
BCM2835_MBOX_INIT_HDR(msg);
BCM2835_MBOX_INIT_TAG(&msg->get_mac_address, GET_MAC_ADDRESS);
@@ -94,11 +175,18 @@ int misc_init_r(void)
if (ret) {
printf("bcm2835: Could not query MAC address\n");
/* Ignore error; not critical */
- return 0;
+ return;
}
eth_setenv_enetaddr("usbethaddr", msg->get_mac_address.body.resp.mac);
+ return;
+}
+
+int misc_init_r(void)
+{
+ set_fdtfile();
+ set_usbethaddr();
return 0;
}
@@ -126,8 +214,36 @@ static int power_on_module(u32 module)
return 0;
}
+static void get_board_rev(void)
+{
+ ALLOC_ALIGN_BUFFER(struct msg_get_board_rev, msg, 1, 16);
+ int ret;
+ const char *name;
+
+ BCM2835_MBOX_INIT_HDR(msg);
+ BCM2835_MBOX_INIT_TAG(&msg->get_board_rev, GET_BOARD_REV);
+
+ ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
+ if (ret) {
+ printf("bcm2835: Could not query board revision\n");
+ /* Ignore error; not critical */
+ return;
+ }
+
+ rpi_board_rev = msg->get_board_rev.body.resp.rev;
+ if (rpi_board_rev >= ARRAY_SIZE(models))
+ rpi_board_rev = 0;
+
+ name = models[rpi_board_rev].name;
+ if (!name)
+ name = "Unknown model";
+ printf("RPI model: %s\n", name);
+}
+
int board_init(void)
{
+ get_board_rev();
+
gd->bd->bi_boot_params = 0x100;
return power_on_module(BCM2835_MBOX_POWER_DEVID_USB_HCD);
diff --git a/include/configs/rpi_b.h b/include/configs/rpi_b.h
index 7bf2bfe09a0b..841169cb6c97 100644
--- a/include/configs/rpi_b.h
+++ b/include/configs/rpi_b.h
@@ -176,7 +176,6 @@
"pxefile_addr_r=0x00100000\0" \
"kernel_addr_r=0x01000000\0" \
"fdt_addr_r=0x02000000\0" \
- "fdtfile=bcm2835-rpi-b.dtb\0" \
"ramdisk_addr_r=0x02100000\0" \
#define BOOT_TARGET_DEVICES(func) \
--
1.9.1
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