diff options
Diffstat (limited to 'drivers/mmc/host/dw_mmc-zx.c')
| -rw-r--r-- | drivers/mmc/host/dw_mmc-zx.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/drivers/mmc/host/dw_mmc-zx.c b/drivers/mmc/host/dw_mmc-zx.c new file mode 100644 index 000000000..c06b53933 --- /dev/null +++ b/drivers/mmc/host/dw_mmc-zx.c @@ -0,0 +1,242 @@ +/* + * ZX Specific Extensions for Synopsys DW Multimedia Card Interface driver + * + * Copyright (C) 2016, Linaro Ltd. + * Copyright (C) 2016, ZTE Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/mfd/syscon.h> +#include <linux/mmc/host.h> +#include <linux/mmc/mmc.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#include "dw_mmc.h" +#include "dw_mmc-pltfm.h" +#include "dw_mmc-zx.h" + +struct dw_mci_zx_priv_data { + struct regmap *sysc_base; +}; + +enum delay_type { + DELAY_TYPE_READ, /* read dqs delay */ + DELAY_TYPE_CLK, /* clk sample delay */ +}; + +static int dw_mci_zx_emmc_set_delay(struct dw_mci *host, unsigned int delay, + enum delay_type dflag) +{ + struct dw_mci_zx_priv_data *priv = host->priv; + struct regmap *sysc_base = priv->sysc_base; + unsigned int clksel; + unsigned int loop = 1000; + int ret; + + if (!sysc_base) + return -EINVAL; + + ret = regmap_update_bits(sysc_base, LB_AON_EMMC_CFG_REG0, + PARA_HALF_CLK_MODE | PARA_DLL_BYPASS_MODE | + PARA_PHASE_DET_SEL_MASK | + PARA_DLL_LOCK_NUM_MASK | + DLL_REG_SET | PARA_DLL_START_MASK, + PARA_DLL_START(4) | PARA_DLL_LOCK_NUM(4)); + if (ret) + return ret; + + ret = regmap_read(sysc_base, LB_AON_EMMC_CFG_REG1, &clksel); + if (ret) + return ret; + + if (dflag == DELAY_TYPE_CLK) { + clksel &= ~CLK_SAMP_DELAY_MASK; + clksel |= CLK_SAMP_DELAY(delay); + } else { + clksel &= ~READ_DQS_DELAY_MASK; + clksel |= READ_DQS_DELAY(delay); + } + + regmap_write(sysc_base, LB_AON_EMMC_CFG_REG1, clksel); + regmap_update_bits(sysc_base, LB_AON_EMMC_CFG_REG0, + PARA_DLL_START_MASK | PARA_DLL_LOCK_NUM_MASK | + DLL_REG_SET, + PARA_DLL_START(4) | PARA_DLL_LOCK_NUM(4) | + DLL_REG_SET); + + do { + ret = regmap_read(sysc_base, LB_AON_EMMC_CFG_REG2, &clksel); + if (ret) + return ret; + + } while (--loop && !(clksel & ZX_DLL_LOCKED)); + + if (!loop) { + dev_err(host->dev, "Error: %s dll lock fail\n", __func__); + return -EIO; + } + + return 0; +} + +static int dw_mci_zx_emmc_execute_tuning(struct dw_mci_slot *slot, u32 opcode) +{ + struct dw_mci *host = slot->host; + struct mmc_host *mmc = slot->mmc; + int ret, len = 0, start = 0, end = 0, delay, best = 0; + + for (delay = 1; delay < 128; delay++) { + ret = dw_mci_zx_emmc_set_delay(host, delay, DELAY_TYPE_CLK); + if (!ret && mmc_send_tuning(mmc, opcode, NULL)) { + if (start >= 0) { + end = delay - 1; + /* check and update longest good range */ + if ((end - start) > len) { + best = (start + end) >> 1; + len = end - start; + } + } + start = -1; + end = 0; + continue; + } + if (start < 0) + start = delay; + } + + if (start >= 0) { + end = delay - 1; + if ((end - start) > len) { + best = (start + end) >> 1; + len = end - start; + } + } + if (best < 0) + return -EIO; + + dev_info(host->dev, "%s best range: start %d end %d\n", __func__, + start, end); + return dw_mci_zx_emmc_set_delay(host, best, DELAY_TYPE_CLK); +} + +static int dw_mci_zx_prepare_hs400_tuning(struct dw_mci *host, + struct mmc_ios *ios) +{ + int ret; + + /* config phase shift as 90 degree */ + ret = dw_mci_zx_emmc_set_delay(host, 32, DELAY_TYPE_READ); + if (ret < 0) + return -EIO; + + return 0; +} + +static int dw_mci_zx_execute_tuning(struct dw_mci_slot *slot, u32 opcode) +{ + struct dw_mci *host = slot->host; + + if (host->verid == 0x290a) /* only for emmc */ + return dw_mci_zx_emmc_execute_tuning(slot, opcode); + /* TODO: Add 0x210a dedicated tuning for sd/sdio */ + + return 0; +} + +static int dw_mci_zx_parse_dt(struct dw_mci *host) +{ + struct device_node *np = host->dev->of_node; + struct device_node *node; + struct dw_mci_zx_priv_data *priv; + struct regmap *sysc_base; + int ret; + + /* syscon is needed only by emmc */ + node = of_parse_phandle(np, "zte,aon-syscon", 0); + if (node) { + sysc_base = syscon_node_to_regmap(node); + of_node_put(node); + + if (IS_ERR(sysc_base)) { + ret = PTR_ERR(sysc_base); + if (ret != -EPROBE_DEFER) + dev_err(host->dev, "Can't get syscon: %d\n", + ret); + return ret; + } + } else { + return 0; + } + + priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + priv->sysc_base = sysc_base; + host->priv = priv; + + return 0; +} + +static unsigned long zx_dwmmc_caps[3] = { + MMC_CAP_CMD23, + MMC_CAP_CMD23, + MMC_CAP_CMD23, +}; + +static const struct dw_mci_drv_data zx_drv_data = { + .caps = zx_dwmmc_caps, + .num_caps = ARRAY_SIZE(zx_dwmmc_caps), + .execute_tuning = dw_mci_zx_execute_tuning, + .prepare_hs400_tuning = dw_mci_zx_prepare_hs400_tuning, + .parse_dt = dw_mci_zx_parse_dt, +}; + +static const struct of_device_id dw_mci_zx_match[] = { + { .compatible = "zte,zx296718-dw-mshc", .data = &zx_drv_data}, + {}, +}; +MODULE_DEVICE_TABLE(of, dw_mci_zx_match); + +static int dw_mci_zx_probe(struct platform_device *pdev) +{ + const struct dw_mci_drv_data *drv_data; + const struct of_device_id *match; + + match = of_match_node(dw_mci_zx_match, pdev->dev.of_node); + drv_data = match->data; + + return dw_mci_pltfm_register(pdev, drv_data); +} + +static const struct dev_pm_ops dw_mci_zx_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(dw_mci_runtime_suspend, + dw_mci_runtime_resume, + NULL) +}; + +static struct platform_driver dw_mci_zx_pltfm_driver = { + .probe = dw_mci_zx_probe, + .remove = dw_mci_pltfm_remove, + .driver = { + .name = "dwmmc_zx", + .of_match_table = dw_mci_zx_match, + .pm = &dw_mci_zx_dev_pm_ops, + }, +}; + +module_platform_driver(dw_mci_zx_pltfm_driver); + +MODULE_DESCRIPTION("ZTE emmc/sd driver"); +MODULE_LICENSE("GPL v2"); |