summaryrefslogtreecommitdiff
path: root/arch/arm/mach-bcm283x/msg.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-bcm283x/msg.c')
-rw-r--r--arch/arm/mach-bcm283x/msg.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/arm/mach-bcm283x/msg.c b/arch/arm/mach-bcm283x/msg.c
index 08b1bea..facb916 100644
--- a/arch/arm/mach-bcm283x/msg.c
+++ b/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;
+}