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-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html