[U-Boot] [PATCH 3/3] mmc: zynq: Add fdt max-frequency support

[Stefan Herbrechtsmeier]

The maximum supported peripheral clock frequency of the zynq depends on
the IO routing. The MIO and EMIO support a maximum frequency of 50 MHz
respectively 25 MHz. Use the max-frequency value of the device tree to
determine the maximal supported peripheral clock frequency.

Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier at weidmueller.de>

---

 drivers/mmc/zynq_sdhci.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/zynq_sdhci.c b/drivers/mmc/zynq_sdhci.c
index 1b75c5a..c6c46b8 100644
--- a/drivers/mmc/zynq_sdhci.c
+++ b/drivers/mmc/zynq_sdhci.c
@@ -16,6 +16,8 @@
 
 #include <asm/arch/clk.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
 #ifndef CONFIG_ZYNQ_SDHCI_MIN_FREQ
 # define CONFIG_ZYNQ_SDHCI_MIN_FREQ	0
 #endif
@@ -23,6 +25,7 @@
 struct arasan_sdhci_plat {
 	struct mmc_config cfg;
 	struct mmc mmc;
+	unsigned int f_max;
 };
 
 static int arasan_sdhci_probe(struct udevice *dev)
@@ -67,7 +70,7 @@ static int arasan_sdhci_probe(struct udevice *dev)
 
 	host->max_clk = clock;
 
-	ret = sdhci_setup_cfg(&plat->cfg, host, CONFIG_ZYNQ_SDHCI_MAX_FREQ,
+	ret = sdhci_setup_cfg(&plat->cfg, host, plat->f_max,
 			      CONFIG_ZYNQ_SDHCI_MIN_FREQ);
 	host->mmc = &plat->mmc;
 	if (ret)
@@ -81,11 +84,15 @@ static int arasan_sdhci_probe(struct udevice *dev)
 
 static int arasan_sdhci_ofdata_to_platdata(struct udevice *dev)
 {
+	struct arasan_sdhci_plat *plat = dev_get_platdata(dev);
 	struct sdhci_host *host = dev_get_priv(dev);
 
 	host->name = dev->name;
 	host->ioaddr = (void *)dev_get_addr(dev);
 
+	plat->f_max = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+				"max-frequency", CONFIG_ZYNQ_SDHCI_MAX_FREQ);
+
 	return 0;
 }
 
-- 
2.7.4



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Komplementärin: Weidmüller Interface Führungsgesellschaft mbH - 
Sitz: Detmold - Amtsgericht Lemgo HRB 3924; 
Geschäftsführer: José Carlos Álvarez Tobar, Elke Eckstein, Dr. Peter Köhler, Jörg Timmermann;
USt-ID-Nr. DE124599660