2016-10-28 13:16 GMT+08:00 Jaehoon Chung <jh80.chung@xxxxxxxxxxx>:
> On 10/28/2016 11:37 AM, Jun Nie wrote:
>> This platform driver adds initial support for the DW host controller
>> found on ZTE SoCs.
>>
>> It has been tested on ZX296718 EVB board currently. More support on
>> timing tuning will be added when hardware is available.
>>
>> Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
>> ---
>> drivers/mmc/host/Kconfig | 9 ++
>> drivers/mmc/host/Makefile | 1 +
>> drivers/mmc/host/dw_mmc-zx.c | 230 +++++++++++++++++++++++++++++++++++++++++++
>> drivers/mmc/host/dw_mmc-zx.h | 23 +++++
>> 4 files changed, 263 insertions(+)
>> create mode 100644 drivers/mmc/host/dw_mmc-zx.c
>> create mode 100644 drivers/mmc/host/dw_mmc-zx.h
>>
>> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
>> index 5274f50..2b3202c 100644
>> --- a/drivers/mmc/host/Kconfig
>> +++ b/drivers/mmc/host/Kconfig
>> @@ -662,6 +662,15 @@ config MMC_DW_ROCKCHIP
>> Synopsys DesignWare Memory Card Interface driver. Select this option
>> for platforms based on RK3066, RK3188 and RK3288 SoC's.
>>
>> +config MMC_DW_ZX
>> + tristate "ZTE specific extensions for Synopsys DW Memory Card Interface"
>> + depends on MMC_DW
>
> I guess MMC_DW_ZX depends on your SoC config, doesn't?
Right, will add dependency.
>
>> + select MMC_DW_PLTFM
>> + help
>> + This selects support for ZTE SoC specific extensions to the
>> + Synopsys DesignWare Memory Card Interface driver. Select this option
>> + for platforms based on ZX296718 SoC's.
>> +
>> config MMC_SH_MMCIF
>> tristate "SuperH Internal MMCIF support"
>> depends on HAS_DMA
>> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
>> index e2bdaaf..9766143 100644
>> --- a/drivers/mmc/host/Makefile
>> +++ b/drivers/mmc/host/Makefile
>> @@ -48,6 +48,7 @@ obj-$(CONFIG_MMC_DW_EXYNOS) += dw_mmc-exynos.o
>> obj-$(CONFIG_MMC_DW_K3) += dw_mmc-k3.o
>> obj-$(CONFIG_MMC_DW_PCI) += dw_mmc-pci.o
>> obj-$(CONFIG_MMC_DW_ROCKCHIP) += dw_mmc-rockchip.o
>> +obj-$(CONFIG_MMC_DW_ZX) += dw_mmc-zx.o
>> obj-$(CONFIG_MMC_SH_MMCIF) += sh_mmcif.o
>> obj-$(CONFIG_MMC_JZ4740) += jz4740_mmc.o
>> obj-$(CONFIG_MMC_VUB300) += vub300.o
>> diff --git a/drivers/mmc/host/dw_mmc-zx.c b/drivers/mmc/host/dw_mmc-zx.c
>> new file mode 100644
>> index 0000000..0404f8e
>> --- /dev/null
>> +++ b/drivers/mmc/host/dw_mmc-zx.c
>> @@ -0,0 +1,230 @@
>> +/*
>> + * 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/dw_mmc.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"
>> +
>> +#define ZX_DLL_LOCKED BIT(2)
>
> Some DLL rigsters and bits are defined in dw_mmc-zx.h.
> why defined ZX_DLL_LOCKED at here.
>
> You can choose that all defines locates to dw_mmc-zx.c or dw_mmc-zx.h
>
Will move together.
>> +
>> +struct dw_mci_zx_priv_data {
>> + struct regmap *sysc_base;
>> +};
>> +
>> +static int dw_mci_zx_emmc_set_delay(struct dw_mci *host, unsigned int delay,
>> + unsigned int clk_flag)
>
> Why do you use "unsigned int" as clk_flag? It's just use one of 0 and 1.
> And 0 and 1 are what means? On/Off?
>
Yes, enumeration shall looks better here. It is a flag for different
delay type. Will change to enumeration.
>> +{
>> + 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;
>> +
>
> priv->sysc_base doesn't never NULL?
For this SoC, it is never NULL if dts is correct. Adding a check is
better anyway.
>
>> + ret = regmap_write(sysc_base, LB_AON_EMMC_CFG_REG0,
>> + PARA_DLL_START_POINT(4) | PARA_DLL_LOCK_NUM(4));
>
> Could you add the comment for controlling this regs?
> I'm not sure because i didn't have ZX TRM..but PARA_DLL_LOCK_NUM should be locked?
>
> It doesn't affect to other bit?
> I think you can use the regmap_update_bits instead of regmap_write.
It does not affect other bit as all bits are write as desired. But
your suggestion make it clearer.
>
>> + if (ret)
>> + return ret;
>> +
>> + ret = regmap_read(sysc_base, LB_AON_EMMC_CFG_REG1, &clksel);
>> + if (ret)
>> + return ret;
>> +
>> + if (clk_flag) {
>> + clksel &= ~(CLK_SAMP_DELAY(0x7F));
>
> It's meaningless..CLK_SAMP_DELAY used only at here.
> CLK_SAMP_DELAY ((x) & 0x7F << 0)
>
> It's just CLK_SAMP_DELAY_MASK.?
>
> #define CLK_SAMP_DELAY_MASK (0x7F << 0)
> clksel &= ~CLK_SAMP_DELAY_MASK;
>
Right, clearer.
>
>> + clksel |= (delay << 8);
>
> Use the CLK_SAMP_DELAY_SHIFT instead of 8.
>
>> + } else {
>> + clksel &= ~(READ_DQS_DELAY(0x7F));
>
> Ditto.
> And i think it also can be changed to regmap_update_bits.
>
>> + clksel |= delay;
>> + }
>> +
>> + regmap_write(sysc_base, LB_AON_EMMC_CFG_REG1, clksel);
>> + regmap_write(sysc_base, LB_AON_EMMC_CFG_REG0,
>> + PARA_DLL_START_POINT(4) | PARA_DLL_LOCK_NUM(4) |
>> + DLL_REG_SET);
>
> regmap_update_bits?
Will do.
>
>> +
>> + 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 len, start = 0, end = 0, delay, best = 0;
>> + int ret = 0;
>> +
>> + for (delay = 1 ; delay < 128; delay++) {
>> + ret = dw_mci_zx_emmc_set_delay(host, delay, 1);
>> + if (ret)
>> + return ret;
>
> When it's failed, just returned.
> Doesn't need to try with next delay value?
Yes, more retry make robust.
>
>> +
>> + if (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);
>> + dw_mci_zx_emmc_set_delay(host, best, 1);
>> + return 0;
>> +}
>> +
>> +static int dw_mci_zx_prepare_hs400_tuning(struct dw_mci *host,
>> + struct mmc_ios *ios)
>> +{
>> + int ret;
>> +
>> + /* config phase shift 90 */
>> + ret = dw_mci_zx_emmc_set_delay(host, 32, 0);
>
> It's always fixed to 32? What means 32?
It means 90 degree shift for value 32. This configuration comes from
ZTE engineer as I do not have hardware for this tuning. Let's just
keep it with adding more comments till tuning is needed.
>
>> + 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) /* emmc */
>> + return dw_mci_zx_emmc_execute_tuning(slot, opcode);
>
> I didn't know why you check host->verid is 2.90a..
> Is there any reason?
There are two version DW MMC IP on this SoC and different
configuration is needed for them. I do not have hardware for tuning
version 210A timing and will be added later.
>
>> +
>> + 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;
>> +
>> + node = of_parse_phandle(np, "zte,aon-syscon", 0);
>> + if (node) {
>> + sysc_base = syscon_node_to_regmap(node);
>> + of_node_put(node);
>
> Use the syscon_regmap_lookup_by_phandle(). It's same behavior.
Will do.
>
>> +
>> + 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;
>> + }
>> + }
>> +
>> + priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> + priv->sysc_base = sysc_base;
>
> Is there no case that sysc_base is NULL?
sysc_base is needed only for eMMC. So it is NULL for SD/MMC cases, and
we can save memory for SD/MMC cases here :)
>
>> + 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,
>> + .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,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");
>> diff --git a/drivers/mmc/host/dw_mmc-zx.h b/drivers/mmc/host/dw_mmc-zx.h
>> new file mode 100644
>> index 0000000..b1aac52
>> --- /dev/null
>> +++ b/drivers/mmc/host/dw_mmc-zx.h
>> @@ -0,0 +1,23 @@
>> +#ifndef _DW_MMC_ZX_H_
>> +#define _DW_MMC_ZX_H_
>> +
>> +/* dll reg offset*/
>> +#define LB_AON_EMMC_CFG_REG0 0x1B0
>> +#define LB_AON_EMMC_CFG_REG1 0x1B4
>> +#define LB_AON_EMMC_CFG_REG2 0x1B8
>> +
>> +/* LB_AON_EMMC_CFG_REG0 register defines */
>> +#define PARA_DLL_START_POINT(x) (((x) & 0xFF) << 0)
>> +#define DLL_REG_SET BIT(8)
>> +#define PARA_DLL_LOCK_NUM(x) (((x) & 7) << 16)
>> +#define PARA_PHASE_DET_SEL(x) (((x) & 7) << 20)
>> +#define PARA_DLL_BYPASS_MODE BIT(23)
>> +#define PARA_HALF_CLK_MODE BIT(24)
>
> PAR_PHASE_DET_SEL/PARA_DLL_BYPASS_MODE_BIT/PARA_HALF_CLK_MODE are never used anywhere.
>
>> +
>> +/* LB_AON_EMMC_CFG_REG1 register defines */
>> +#define READ_DQS_DELAY(x) (((x) & 0x7F) << 0)
>> +#define READ_DQS_BYPASS_MODE BIT(7)
>> +#define CLK_SAMP_DELAY(x) (((x) & 0x7F) << 8)
>> +#define CLK_SAMP_BYPASS_MODE BIT(15)
>
> Also READ_DQS_BYPASS_MODe/CLK_SAMP_BYBASS_MODE didnt used anywhere.
>
>
> Hmm. These are not dwmmc host controller's register.
> So If you needs to add these defines..I think you needs to add dessriptions in more detail.
>
> At least..Which board's DLL reg offset.
>
> Best Regards,
> Jaehoon Chung
>
>> +
>> +#endif /* _DW_MMC_ZX_H_ */
>>
>
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