arm: rpi: Add a function to obtain the MMC clock

Move this code into the new message handler file.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/arm/mach-bcm283x/include/mach/msg.h

@@ -15,4 +15,11 @@
  */
 int bcm2835_power_on_module(u32 module);
 
+/**
+ * bcm2835_get_mmc_clock() - get the frequency of the MMC clock
+ *
+ * @return clock frequency, or -ve on error
+ */
+int bcm2835_get_mmc_clock(void);
+
 #endif

arch/arm/mach-bcm283x/msg.c

@@ -14,6 +14,12 @@ struct msg_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;
+	u32 end_tag;
+};
+
 int bcm2835_power_on_module(u32 module)
 {
 	ALLOC_CACHE_ALIGN_BUFFER(struct msg_set_power_state, msg_pwr, 1);
@@ -37,3 +43,25 @@ int bcm2835_power_on_module(u32 module)
 
 	return 0;
 }
+
+int bcm2835_get_mmc_clock(void)
+{
+	ALLOC_CACHE_ALIGN_BUFFER(struct msg_get_clock_rate, msg_clk, 1);
+	int ret;
+
+	ret = bcm2835_power_on_module(BCM2835_MBOX_POWER_DEVID_SDHCI);
+	if (ret)
+		return ret;
+
+	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;
+
+	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg_clk->hdr);
+	if (ret) {
+		printf("bcm2835: Could not query eMMC clock rate\n");
+		return -EIO;
+	}
+
+	return msg_clk->get_clock_rate.body.resp.rate_hz;
+}

board/raspberrypi/rpi/rpi.c

@@ -468,23 +468,15 @@ int board_init(void)
 
 int board_mmc_init(bd_t *bis)
 {
-	ALLOC_CACHE_ALIGN_BUFFER(struct msg_get_clock_rate, msg_clk, 1);
 	int ret;
 
 	bcm2835_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;
+	ret = bcm2835_get_mmc_clock();
+	if (ret)
+		return ret;
 
-	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg_clk->hdr);
-	if (ret) {
-		printf("bcm2835: Could not query eMMC clock rate\n");
-		return -1;
-	}
-
-	return bcm2835_sdhci_init(BCM2835_SDHCI_BASE,
-				  msg_clk->get_clock_rate.body.resp.rate_hz);
+	return bcm2835_sdhci_init(BCM2835_SDHCI_BASE, ret);
 }
 
 int ft_board_setup(void *blob, bd_t *bd)