From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
MMCIF IP on R-Car series has parent clock which can be set
several rate, and it was not implemented on old SH-Mobile series
(= SH-Mobile series parent clock was fixed rate)
R-Car series MMCIF can use more high speed access if it setup
parent clock. This patch adds parent clock setup method,
and r8a7790/r8a7791 can use it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@xxxxxxxxxxx>
---
v4 -> v5
- get clock data from compatible
drivers/mmc/host/sh_mmcif.c | 92 ++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 83 insertions(+), 9 deletions(-)
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index e13c5f41..7ade263 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -57,6 +57,7 @@
#include <linux/mmc/slot-gpio.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
+#include <linux/of_device.h>
#include <linux/pagemap.h>
#include <linux/platform_device.h>
#include <linux/pm_qos.h>
@@ -224,6 +225,15 @@ enum sh_mmcif_wait_for {
MMCIF_WAIT_FOR_STOP,
};
+/*
+ * difference for each SoC
+ */
+struct sh_mmcif_ver {
+ u32 clkdiv_map; /* see CE_CLK_CTRL::CLKDIV */
+ unsigned int pf_min; /* parent frequency min */
+ unsigned int pf_max; /* parent frequency max */
+};
+
struct sh_mmcif_host {
struct mmc_host *mmc;
struct mmc_request *mrq;
@@ -248,6 +258,7 @@ struct sh_mmcif_host {
bool ccs_enable; /* Command Completion Signal support */
bool clk_ctrl2_enable;
struct mutex thread_lock;
+ const struct sh_mmcif_ver *ver;
/* DMA support */
struct dma_chan *chan_rx;
@@ -256,8 +267,16 @@ struct sh_mmcif_host {
bool dma_active;
};
+static const struct sh_mmcif_ver sh_mmcif_gen2 = {
+ .clkdiv_map = 0x3ff,
+ .pf_min = 12187500,
+ .pf_max = 97500000,
+};
+
static const struct of_device_id sh_mmcif_of_match[] = {
{ .compatible = "renesas,sh-mmcif" },
+ { .compatible = "renesas,mmcif-r8a7790", .data = &sh_mmcif_gen2 },
+ { .compatible = "renesas,mmcif-r8a7791", .data = &sh_mmcif_gen2 },
{ }
};
MODULE_DEVICE_TABLE(of, sh_mmcif_of_match);
@@ -492,19 +511,56 @@ static void sh_mmcif_clock_control(struct sh_mmcif_host *host, unsigned int clk)
struct sh_mmcif_plat_data *p = dev->platform_data;
bool sup_pclk = p ? p->sup_pclk : false;
unsigned int current_clk = clk_get_rate(host->clk);
+ unsigned int clkdiv;
sh_mmcif_bitclr(host, MMCIF_CE_CLK_CTRL, CLK_ENABLE);
sh_mmcif_bitclr(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR);
if (!clk)
return;
- if (sup_pclk && clk == current_clk)
- sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_SUP_PCLK);
- else
- sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR &
- ((fls(DIV_ROUND_UP(current_clk,
- clk) - 1) - 1) << 16));
+ if (host->ver) {
+ const struct sh_mmcif_ver *ver = host->ver;
+ unsigned int freq, best_freq, myclk, div, diff_min, diff;
+ int i;
+
+ clkdiv = 0;
+ diff_min = ~0;
+ best_freq = 0;
+ for (i = 31; i >= 0; i--) {
+ if (!((1 << i) & ver->clkdiv_map))
+ continue;
+
+ /*
+ * clk = parent_freq / div
+ * -> parent_freq = clk x div
+ */
+
+ div = 1 << (i + 1);
+ freq = clk_round_rate(host->clk, clk * div);
+ myclk = freq / div;
+ diff = (myclk > clk) ? myclk - clk : clk - myclk;
+
+ if (diff <= diff_min) {
+ best_freq = freq;
+ clkdiv = i;
+ diff_min = diff;
+ }
+ }
+
+ dev_dbg(dev, "clk %u/%u (%u, 0x%x)\n",
+ (best_freq / (1 << (clkdiv + 1))), clk,
+ best_freq, clkdiv);
+
+ clk_set_rate(host->clk, best_freq);
+ clkdiv = clkdiv << 16;
+ } else if (sup_pclk && clk == current_clk) {
+ clkdiv = CLK_SUP_PCLK;
+ } else {
+ clkdiv = (fls(DIV_ROUND_UP(current_clk, clk) - 1) - 1) << 16;
+ }
+
+ sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR & clkdiv);
sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_ENABLE);
}
@@ -1000,10 +1056,28 @@ static void sh_mmcif_request(struct mmc_host *mmc, struct mmc_request *mrq)
static void sh_mmcif_clk_setup(struct sh_mmcif_host *host)
{
- unsigned int clk = clk_get_rate(host->clk);
+ struct device *dev = sh_mmcif_host_to_dev(host);
+ const struct of_device_id *of_id;
+ const struct sh_mmcif_ver *ver = NULL;
+
+ of_id = of_match_device(sh_mmcif_of_match, dev);
+ if (of_id)
+ ver = of_id->data;
+
+ if (ver) {
+ host->mmc->f_min = ver->pf_min / (1 << fls(ver->clkdiv_map));
+ host->mmc->f_max = ver->pf_max / (1 << ffs(ver->clkdiv_map));
+
+ host->ver = ver;
+ } else {
+ unsigned int clk = clk_get_rate(host->clk);
+
+ host->mmc->f_max = clk / 2;
+ host->mmc->f_min = clk / 512;
+ }
- host->mmc->f_max = clk / 2;
- host->mmc->f_min = clk / 512;
+ dev_dbg(dev, "clk max/min = %d/%d\n",
+ host->mmc->f_max, host->mmc->f_min);
}
static void sh_mmcif_set_power(struct sh_mmcif_host *host, struct mmc_ios *ios)
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
