This patch focuses on clock setting for RK3288 mmc controller.
In RK3288 mmc controller, CLKDIV register can only be set 0 or 1,
and if DDR 8bit mode, CLKDIV register must be set 1.
Signed-off-by: Addy Ke <addy.ke@xxxxxxxxxxxxxx>
---
changes since v1:
- dw_mci_rk3288_setup_clock: do not call clk_get_rate(), just use the
host->bus_hz which is already called by dw_mmc.c, suggested by Jaehoon Chung
.../devicetree/bindings/mmc/rockchip-dw-mshc.txt | 4 +-
drivers/mmc/host/dw_mmc-pltfm.c | 50 +++++++++++++++++++++-
2 files changed, 51 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
index c559f3f..e3f95cd 100644
--- a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
+++ b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt
@@ -10,7 +10,9 @@ extensions to the Synopsys Designware Mobile Storage Host Controller.
Required Properties:
* compatible: should be
- - "rockchip,rk2928-dw-mshc": for Rockchip RK2928 and following
+ - "rockchip,rk2928-dw-mshc": for Rockchip RK2928 and following,
+ before RK3288
+ - "rockchip,rk3288-dw-mshc": for Rockchip RK3288
Example:
diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c
index d4a47a9..809c28b 100644
--- a/drivers/mmc/host/dw_mmc-pltfm.c
+++ b/drivers/mmc/host/dw_mmc-pltfm.c
@@ -21,17 +21,61 @@
#include <linux/mmc/mmc.h>
#include <linux/mmc/dw_mmc.h>
#include <linux/of.h>
+#include <linux/clk.h>
#include "dw_mmc.h"
#include "dw_mmc-pltfm.h"
+#define RK3288_CLKGEN_DIV 2
+
static void dw_mci_pltfm_prepare_command(struct dw_mci *host, u32 *cmdr)
{
*cmdr |= SDMMC_CMD_USE_HOLD_REG;
}
-static const struct dw_mci_drv_data rockchip_drv_data = {
+static int dw_mci_rk3288_setup_clock(struct dw_mci *host)
+{
+ host->bus_hz /= RK3288_CLKGEN_DIV;
+
+ return 0;
+}
+
+static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
+{
+ int ret;
+ unsigned int cclkin;
+
+ /*
+ * cclkin: source clock of mmc controller.
+ * bus_hz: card interface clock generated by CLKGEN.
+ * bus_hz = cclkin / RK3288_CLKGEN_DIV;
+ * ios->clock = (div == 0) ? bus_hz : (bus_hz / (2 * div))
+ *
+ * Note: div can only be 0 or 1
+ * if DDR50 8bit mode, div must be set 1
+ */
+ if ((ios->bus_width == MMC_BUS_WIDTH_8) &&
+ (ios->timing == MMC_TIMING_UHS_DDR50 ||
+ ios->timing == MMC_TIMING_MMC_DDR52))
+ cclkin = 2 * ios->clock * RK3288_CLKGEN_DIV;
+ else
+ cclkin = ios->clock * RK3288_CLKGEN_DIV;
+
+ ret = clk_set_rate(host->ciu_clk, cclkin);
+ if (ret)
+ dev_warn(host->dev, "failed to set rate %uHz\n", ios->clock);
+
+ host->bus_hz = clk_get_rate(host->ciu_clk) / RK3288_CLKGEN_DIV;
+}
+
+static const struct dw_mci_drv_data rk2928_drv_data = {
+ .prepare_command = dw_mci_pltfm_prepare_command,
+};
+
+static const struct dw_mci_drv_data rk3288_drv_data = {
.prepare_command = dw_mci_pltfm_prepare_command,
+ .set_ios = dw_mci_rk3288_set_ios,
+ .setup_clock = dw_mci_rk3288_setup_clock,
};
static const struct dw_mci_drv_data socfpga_drv_data = {
@@ -95,7 +139,9 @@ EXPORT_SYMBOL_GPL(dw_mci_pltfm_pmops);
static const struct of_device_id dw_mci_pltfm_match[] = {
{ .compatible = "snps,dw-mshc", },
{ .compatible = "rockchip,rk2928-dw-mshc",
- .data = &rockchip_drv_data },
+ .data = &rk2928_drv_data },
+ { .compatible = "rockchip,rk3288-dw-mshc",
+ .data = &rk3288_drv_data },
{ .compatible = "altr,socfpga-dw-mshc",
.data = &socfpga_drv_data },
{},
--
1.8.3.2
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