[PATCH v11 3/3] mmc: sdhci-msm: Add platform_execute_tuning implementation
From: Georgi Djakov
Date: Mon Mar 10 2014 - 11:38:24 EST
This patch adds implementation for platform specific tuning in order to support
HS200 bus speed mode on Qualcomm SDHCI controller.
Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
Signed-off-by: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>
Signed-off-by: Georgi Djakov <gdjakov@xxxxxxxxxx>
---
drivers/mmc/host/sdhci-msm.c | 420 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 415 insertions(+), 5 deletions(-)
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 3b0606f..acb0e9e 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -18,6 +18,8 @@
#include <linux/of_device.h>
#include <linux/regulator/consumer.h>
#include <linux/delay.h>
+#include <linux/mmc/mmc.h>
+#include <linux/slab.h>
#include "sdhci-pltfm.h"
@@ -26,6 +28,42 @@
#define CORE_POWER 0x0
#define CORE_SW_RST BIT(7)
+#define MAX_PHASES 16
+#define CORE_DLL_LOCK BIT(7)
+#define CORE_DLL_EN BIT(16)
+#define CORE_CDR_EN BIT(17)
+#define CORE_CK_OUT_EN BIT(18)
+#define CORE_CDR_EXT_EN BIT(19)
+#define CORE_DLL_PDN BIT(29)
+#define CORE_DLL_RST BIT(30)
+#define CORE_DLL_CONFIG 0x100
+#define CORE_DLL_STATUS 0x108
+
+#define CORE_VENDOR_SPEC 0x10c
+#define CORE_CLK_PWRSAVE BIT(1)
+
+#define CDR_SELEXT_SHIFT 20
+#define CDR_SELEXT_MASK (0xf << CDR_SELEXT_SHIFT)
+#define CMUX_SHIFT_PHASE_SHIFT 24
+#define CMUX_SHIFT_PHASE_MASK (7 << CMUX_SHIFT_PHASE_SHIFT)
+
+static const u32 tuning_block_64[] = {
+ 0x00ff0fff, 0xccc3ccff, 0xffcc3cc3, 0xeffefffe,
+ 0xddffdfff, 0xfbfffbff, 0xff7fffbf, 0xefbdf777,
+ 0xf0fff0ff, 0x3cccfc0f, 0xcfcc33cc, 0xeeffefff,
+ 0xfdfffdff, 0xffbfffdf, 0xfff7ffbb, 0xde7b7ff7
+};
+
+static const u32 tuning_block_128[] = {
+ 0xff00ffff, 0x0000ffff, 0xccccffff, 0xcccc33cc,
+ 0xcc3333cc, 0xffffcccc, 0xffffeeff, 0xffeeeeff,
+ 0xffddffff, 0xddddffff, 0xbbffffff, 0xbbffffff,
+ 0xffffffbb, 0xffffff77, 0x77ff7777, 0xffeeddbb,
+ 0x00ffffff, 0x00ffffff, 0xccffff00, 0xcc33cccc,
+ 0x3333cccc, 0xffcccccc, 0xffeeffff, 0xeeeeffff,
+ 0xddffffff, 0xddffffff, 0xffffffdd, 0xffffffbb,
+ 0xffffbbbb, 0xffff77ff, 0xff7777ff, 0xeeddbb77
+};
struct sdhci_msm_host {
struct platform_device *pdev;
@@ -38,17 +76,389 @@ struct sdhci_msm_host {
};
/* Platform specific tuning */
-static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
+static inline int msm_dll_poll_ck_out_en(struct sdhci_host *host, u8 poll)
+{
+ u32 wait_cnt = 50;
+ u8 ck_out_en;
+ struct mmc_host *mmc = host->mmc;
+
+ /* Poll for CK_OUT_EN bit. max. poll time = 50us */
+ ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
+ CORE_CK_OUT_EN);
+
+ while (ck_out_en != poll) {
+ if (--wait_cnt == 0) {
+ dev_err(mmc_dev(mmc), "%s: CK_OUT_EN bit is not %d\n",
+ mmc_hostname(mmc), poll);
+ return -ETIMEDOUT;
+ }
+ udelay(1);
+
+ ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
+ CORE_CK_OUT_EN);
+ }
+
+ return 0;
+}
+
+static int msm_config_cm_dll_phase(struct sdhci_host *host, u8 phase)
+{
+ int rc;
+ static const u8 grey_coded_phase_table[] = {
+ 0x0, 0x1, 0x3, 0x2, 0x6, 0x7, 0x5, 0x4,
+ 0xc, 0xd, 0xf, 0xe, 0xa, 0xb, 0x9, 0x8
+ };
+ unsigned long flags;
+ u32 config;
+ struct mmc_host *mmc = host->mmc;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
+ config &= ~(CORE_CDR_EN | CORE_CK_OUT_EN);
+ config |= (CORE_CDR_EXT_EN | CORE_DLL_EN);
+ writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '0' */
+ rc = msm_dll_poll_ck_out_en(host, 0);
+ if (rc)
+ goto err_out;
+
+ /*
+ * Write the selected DLL clock output phase (0 ... 15)
+ * to CDR_SELEXT bit field of DLL_CONFIG register.
+ */
+ config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
+ config &= ~CDR_SELEXT_MASK;
+ config |= grey_coded_phase_table[phase] << CDR_SELEXT_SHIFT;
+ writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Set CK_OUT_EN bit of DLL_CONFIG register to 1. */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ | CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '1' */
+ rc = msm_dll_poll_ck_out_en(host, 1);
+ if (rc)
+ goto err_out;
+
+ config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
+ config |= CORE_CDR_EN;
+ config &= ~CORE_CDR_EXT_EN;
+ writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
+ goto out;
+
+err_out:
+ dev_err(mmc_dev(mmc), "%s: Failed to set DLL phase: %d\n",
+ mmc_hostname(mmc), phase);
+out:
+ spin_unlock_irqrestore(&host->lock, flags);
+ return rc;
+}
+
+/*
+ * Find out the greatest range of consecuitive selected
+ * DLL clock output phases that can be used as sampling
+ * setting for SD3.0 UHS-I card read operation (in SDR104
+ * timing mode) or for eMMC4.5 card read operation (in HS200
+ * timing mode).
+ * Select the 3/4 of the range and configure the DLL with the
+ * selected DLL clock output phase.
+ */
+
+static int msm_find_most_appropriate_phase(struct sdhci_host *host,
+ u8 *phase_table, u8 total_phases)
+{
+ int ret;
+ u8 ranges[MAX_PHASES][MAX_PHASES] = { {0}, {0} };
+ u8 phases_per_row[MAX_PHASES] = { 0 };
+ int row_index = 0, col_index = 0, selected_row_index = 0, curr_max = 0;
+ int i, cnt, phase_0_raw_index = 0, phase_15_raw_index = 0;
+ bool phase_0_found = false, phase_15_found = false;
+ struct mmc_host *mmc = host->mmc;
+
+ if (!total_phases || (total_phases > MAX_PHASES)) {
+ dev_err(mmc_dev(mmc), "%s: Invalid argument: total_phases=%d\n",
+ mmc_hostname(mmc), total_phases);
+ return -EINVAL;
+ }
+
+ for (cnt = 0; cnt < total_phases; cnt++) {
+ ranges[row_index][col_index] = phase_table[cnt];
+ phases_per_row[row_index] += 1;
+ col_index++;
+
+ if ((cnt + 1) == total_phases) {
+ continue;
+ /* check if next phase in phase_table is consecutive or not */
+ } else if ((phase_table[cnt] + 1) != phase_table[cnt + 1]) {
+ row_index++;
+ col_index = 0;
+ }
+ }
+
+ if (row_index >= MAX_PHASES)
+ return -EINVAL;
+
+ /* Check if phase-0 is present in first valid window? */
+ if (!ranges[0][0]) {
+ phase_0_found = true;
+ phase_0_raw_index = 0;
+ /* Check if cycle exist between 2 valid windows */
+ for (cnt = 1; cnt <= row_index; cnt++) {
+ if (phases_per_row[cnt]) {
+ for (i = 0; i < phases_per_row[cnt]; i++) {
+ if (ranges[cnt][i] == 15) {
+ phase_15_found = true;
+ phase_15_raw_index = cnt;
+ break;
+ }
+ }
+ }
+ }
+ }
+
+ /* If 2 valid windows form cycle then merge them as single window */
+ if (phase_0_found && phase_15_found) {
+ /* number of phases in raw where phase 0 is present */
+ u8 phases_0 = phases_per_row[phase_0_raw_index];
+ /* number of phases in raw where phase 15 is present */
+ u8 phases_15 = phases_per_row[phase_15_raw_index];
+
+ if (phases_0 + phases_15 >= MAX_PHASES)
+ /*
+ * If there are more than 1 phase windows then total
+ * number of phases in both the windows should not be
+ * more than or equal to MAX_PHASES.
+ */
+ return -EINVAL;
+
+ /* Merge 2 cyclic windows */
+ i = phases_15;
+ for (cnt = 0; cnt < phases_0; cnt++) {
+ ranges[phase_15_raw_index][i] =
+ ranges[phase_0_raw_index][cnt];
+ if (++i >= MAX_PHASES)
+ break;
+ }
+
+ phases_per_row[phase_0_raw_index] = 0;
+ phases_per_row[phase_15_raw_index] = phases_15 + phases_0;
+ }
+
+ for (cnt = 0; cnt <= row_index; cnt++) {
+ if (phases_per_row[cnt] > curr_max) {
+ curr_max = phases_per_row[cnt];
+ selected_row_index = cnt;
+ }
+ }
+
+ i = (curr_max * 3) / 4;
+ if (i)
+ i--;
+
+ ret = ranges[selected_row_index][i];
+
+ if (ret >= MAX_PHASES) {
+ ret = -EINVAL;
+ dev_err(mmc_dev(mmc), "%s: Invalid phase selected=%d\n",
+ mmc_hostname(mmc), ret);
+ }
+
+ return ret;
+}
+
+static inline void msm_cm_dll_set_freq(struct sdhci_host *host)
+{
+ u32 mclk_freq = 0, config;
+
+ /* Program the MCLK value to MCLK_FREQ bit field */
+ if (host->clock <= 112000000)
+ mclk_freq = 0;
+ else if (host->clock <= 125000000)
+ mclk_freq = 1;
+ else if (host->clock <= 137000000)
+ mclk_freq = 2;
+ else if (host->clock <= 150000000)
+ mclk_freq = 3;
+ else if (host->clock <= 162000000)
+ mclk_freq = 4;
+ else if (host->clock <= 175000000)
+ mclk_freq = 5;
+ else if (host->clock <= 187000000)
+ mclk_freq = 6;
+ else if (host->clock <= 200000000)
+ mclk_freq = 7;
+
+ config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
+ config &= ~CMUX_SHIFT_PHASE_MASK;
+ config |= mclk_freq << CMUX_SHIFT_PHASE_SHIFT;
+ writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
+}
+
+/* Initialize the DLL (Programmable Delay Line) */
+static int msm_init_cm_dll(struct sdhci_host *host)
{
+ struct mmc_host *mmc = host->mmc;
+ int wait_cnt = 50;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
/*
- * Tuning is required for SDR104, HS200 and HS400 cards and if the clock
- * frequency greater than 100MHz in those modes. The standard tuning
- * procedure should not be executed, but a custom implementation will be
- * added here instead.
+ * Make sure that clock is always enabled when DLL
+ * tuning is in progress. Keeping PWRSAVE ON may
+ * turn off the clock.
*/
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC)
+ & ~CORE_CLK_PWRSAVE), host->ioaddr + CORE_VENDOR_SPEC);
+
+ /* Write 1 to DLL_RST bit of DLL_CONFIG register */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ | CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Write 1 to DLL_PDN bit of DLL_CONFIG register */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ | CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
+ msm_cm_dll_set_freq(host);
+
+ /* Write 0 to DLL_RST bit of DLL_CONFIG register */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ & ~CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Write 0 to DLL_PDN bit of DLL_CONFIG register */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ & ~CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Set DLL_EN bit to 1. */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ | CORE_DLL_EN), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Set CK_OUT_EN bit to 1. */
+ writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
+ | CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
+
+ /* Wait until DLL_LOCK bit of DLL_STATUS register becomes '1' */
+ while (!(readl_relaxed(host->ioaddr + CORE_DLL_STATUS) &
+ CORE_DLL_LOCK)) {
+ /* max. wait for 50us sec for LOCK bit to be set */
+ if (--wait_cnt == 0) {
+ dev_err(mmc_dev(mmc), "%s: DLL failed to LOCK\n",
+ mmc_hostname(mmc));
+ spin_unlock_irqrestore(&host->lock, flags);
+ return -ETIMEDOUT;
+ }
+ udelay(1);
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
return 0;
}
+static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
+{
+ int tuning_seq_cnt = 3;
+ u8 phase, *data_buf, tuned_phases[16], tuned_phase_cnt = 0;
+ const u32 *tuning_block_pattern = tuning_block_64;
+ int size = sizeof(tuning_block_64); /* Pattern size in bytes */
+ int rc;
+ struct mmc_host *mmc = host->mmc;
+ struct mmc_ios ios = host->mmc->ios;
+
+ /*
+ * Tuning is required for SDR104, HS200 and HS400 cards and
+ * if clock frequency is greater than 100MHz in these modes.
+ */
+ if (host->clock <= 100 * 1000 * 1000 ||
+ !((ios.timing == MMC_TIMING_MMC_HS200) ||
+ (ios.timing == MMC_TIMING_UHS_SDR104)))
+ return 0;
+
+ if ((opcode == MMC_SEND_TUNING_BLOCK_HS200) &&
+ (mmc->ios.bus_width == MMC_BUS_WIDTH_8)) {
+ tuning_block_pattern = tuning_block_128;
+ size = sizeof(tuning_block_128);
+ }
+
+ data_buf = kmalloc(size, GFP_KERNEL);
+ if (!data_buf)
+ return -ENOMEM;
+
+retry:
+ /* First of all reset the tuning block */
+ rc = msm_init_cm_dll(host);
+ if (rc)
+ goto out;
+
+ phase = 0;
+ do {
+ struct mmc_command cmd = { 0 };
+ struct mmc_data data = { 0 };
+ struct mmc_request mrq = {
+ .cmd = &cmd,
+ .data = &data
+ };
+ struct scatterlist sg;
+
+ /* Set the phase in delay line hw block */
+ rc = msm_config_cm_dll_phase(host, phase);
+ if (rc)
+ goto out;
+
+ cmd.opcode = opcode;
+ cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
+
+ data.blksz = size;
+ data.blocks = 1;
+ data.flags = MMC_DATA_READ;
+ data.timeout_ns = NSEC_PER_SEC; /* 1 second */
+
+ data.sg = &sg;
+ data.sg_len = 1;
+ sg_init_one(&sg, data_buf, size);
+ memset(data_buf, 0, size);
+ mmc_wait_for_req(mmc, &mrq);
+
+ if (!cmd.error && !data.error &&
+ !memcmp(data_buf, tuning_block_pattern, size)) {
+ /* Tuning is successful at this tuning point */
+ tuned_phases[tuned_phase_cnt++] = phase;
+ dev_dbg(mmc_dev(mmc), "%s: Found good phase = %d\n",
+ mmc_hostname(mmc), phase);
+ }
+ } while (++phase < ARRAY_SIZE(tuned_phases));
+
+ if (tuned_phase_cnt) {
+ rc = msm_find_most_appropriate_phase(host, tuned_phases,
+ tuned_phase_cnt);
+ if (rc < 0)
+ goto out;
+ else
+ phase = rc;
+
+ /*
+ * Finally set the selected phase in delay
+ * line hw block.
+ */
+ rc = msm_config_cm_dll_phase(host, phase);
+ if (rc)
+ goto out;
+ dev_dbg(mmc_dev(mmc), "%s: Setting the tuning phase to %d\n",
+ mmc_hostname(mmc), phase);
+ } else {
+ if (--tuning_seq_cnt)
+ goto retry;
+ /* Tuning failed */
+ dev_dbg(mmc_dev(mmc), "%s: No tuning point found\n",
+ mmc_hostname(mmc));
+ rc = -EIO;
+ }
+
+out:
+ kfree(data_buf);
+ return rc;
+}
+
static const struct of_device_id sdhci_msm_dt_match[] = {
{ .compatible = "qcom,sdhci-msm-v4" },
{},
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/