// SPDX-License-Identifier: GPL-2.0-only
/*
* Modified from dw_mmc-hi3798cv200.c
*
* Copyright (c) 2024 Yang Xiwen <[email protected]>
* Copyright (c) 2018 HiSilicon Technologies Co., Ltd.
*/
#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/mmc/host.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include "dw_mmc.h"
#include "dw_mmc-pltfm.h"
#define SDMMC_TUNING_CTRL 0x118
#define SDMMC_TUNING_FIND_EDGE BIT(5)
#define ALL_INT_CLR 0x1ffff
/* DLL ctrl reg */
#define SAP_DLL_CTRL_DLLMODE BIT(16)
struct dw_mci_hi3798mv200_priv {
struct clk *sample_clk;
struct clk *drive_clk;
struct regmap *crg_reg;
u32 sap_dll_offset;
struct mmc_clk_phase_map phase_map;
};
static void dw_mci_hi3798mv200_set_ios(struct dw_mci *host, struct mmc_ios *ios)
{
struct dw_mci_hi3798mv200_priv *priv = host->priv;
struct mmc_clk_phase phase = priv->phase_map.phase[ios->timing];
u32 val;
val = mci_readl(host, ENABLE_SHIFT);
if (ios->timing == MMC_TIMING_MMC_DDR52
|| ios->timing == MMC_TIMING_UHS_DDR50)
val |= SDMMC_ENABLE_PHASE;
else
val &= ~SDMMC_ENABLE_PHASE;
mci_writel(host, ENABLE_SHIFT, val);
val = mci_readl(host, DDR_REG);
if (ios->timing == MMC_TIMING_MMC_HS400)
val |= SDMMC_DDR_HS400;
else
val &= ~SDMMC_DDR_HS400;
mci_writel(host, DDR_REG, val);
if (clk_set_rate(host->ciu_clk, ios->clock))
dev_warn(host->dev, "Failed to set rate to %u\n", ios->clock);
else
/*
* CLK_MUX_ROUND_NEAREST is enabled for this clock
* The actual clock rate is not what we set, but a rounded value
* so we should get the rate once again
*/
host->bus_hz = clk_get_rate(host->ciu_clk);
if (phase.valid) {
clk_set_phase(priv->drive_clk, phase.out_deg);
clk_set_phase(priv->sample_clk, phase.in_deg);
} else {
dev_warn(host->dev,
"The phase entry for timing mode %d is missing in device tree.\n",
ios->timing);
}
}
static inline int dw_mci_hi3798mv200_enable_tuning(struct dw_mci_slot *slot)
{
struct dw_mci_hi3798mv200_priv *priv = slot->host->priv;
return regmap_clear_bits(priv->crg_reg, priv->sap_dll_offset, SAP_DLL_CTRL_DLLMODE);
}
static inline int dw_mci_hi3798mv200_disable_tuning(struct dw_mci_slot *slot)
{
struct dw_mci_hi3798mv200_priv *priv = slot->host->priv;
return regmap_set_bits(priv->crg_reg, priv->sap_dll_offset, SAP_DLL_CTRL_DLLMODE);
}
static int dw_mci_hi3798mv200_execute_tuning_mix_mode(struct dw_mci_slot *slot,
u32 opcode)
{
static const int degrees[] = { 0, 45, 90, 135, 180, 225, 270, 315 };
struct dw_mci *host = slot->host;
struct dw_mci_hi3798mv200_priv *priv = host->priv;
int raise_point = -1, fall_point = -1, mid;
int err, prev_err = -1;
int found = 0;
int regval;
int i;
int ret;
ret = dw_mci_hi3798mv200_enable_tuning(slot);
if (ret < 0)
return ret;
for (i = 0; i < ARRAY_SIZE(degrees); i++) {
clk_set_phase(priv->sample_clk, degrees[i]);
mci_writel(host, RINTSTS, ALL_INT_CLR);
/*
* HiSilicon implemented a tuning mechanism.
* It needs special interaction with the DLL.
*
* Treat edge(flip) found as an error too.
*/
err = mmc_send_tuning(slot->mmc, opcode, NULL);
regval = mci_readl(host, TUNING_CTRL);
if (err || (regval & SDMMC_TUNING_FIND_EDGE))
err = 1;
else
found = 1;
if (i > 0) {
if (err && !prev_err)
fall_point = i - 1;
if (!err && prev_err)
raise_point = i;
}
if (raise_point != -1 && fall_point != -1)
goto tuning_out;
prev_err = err;
}
tuning_out:
ret = dw_mci_hi3798mv200_disable_tuning(slot);
if (ret < 0)
return ret;
if (found) {
if (raise_point == -1)
raise_point = 0;
if (fall_point == -1)
fall_point = ARRAY_SIZE(degrees) - 1;
if (fall_point < raise_point) {
if ((raise_point + fall_point) >
(ARRAY_SIZE(degrees) - 1))
mid = fall_point / 2;
else
mid = (raise_point + ARRAY_SIZE(degrees) - 1) / 2;
} else {
mid = (raise_point + fall_point) / 2;
}
/*
* We don't care what timing we are tuning for,
* simply use the same phase for all timing needs tuning.
*/
priv->phase_map.phase[MMC_TIMING_MMC_HS200].in_deg = degrees[mid];
priv->phase_map.phase[MMC_TIMING_MMC_HS400].in_deg = degrees[mid];
priv->phase_map.phase[MMC_TIMING_UHS_SDR104].in_deg = degrees[mid];
clk_set_phase(priv->sample_clk, degrees[mid]);
dev_dbg(host->dev, "Tuning clk_sample[%d, %d], set[%d]\n",
raise_point, fall_point, degrees[mid]);
ret = 0;
} else {
dev_err(host->dev, "No valid clk_sample shift!\n");
ret = -EINVAL;
}
mci_writel(host, RINTSTS, ALL_INT_CLR);
return ret;
}
static int dw_mci_hi3798mv200_init(struct dw_mci *host)
{
struct dw_mci_hi3798mv200_priv *priv;
struct device_node *np = host->dev->of_node;
int ret;
priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
mmc_of_parse_clk_phase(host->dev, &priv->phase_map);
priv->sample_clk = devm_clk_get_enabled(host->dev, "ciu-sample");
if (IS_ERR(priv->sample_clk))
return dev_err_probe(host->dev, PTR_ERR(priv->sample_clk),
"failed to get enabled ciu-sample clock\n");
priv->drive_clk = devm_clk_get_enabled(host->dev, "ciu-drive");
if (IS_ERR(priv->drive_clk))
return dev_err_probe(host->dev, PTR_ERR(priv->drive_clk),
"failed to get enabled ciu-drive clock\n");
priv->crg_reg = syscon_regmap_lookup_by_phandle(np, "hisilicon,sap-dll-reg");
if (IS_ERR(priv->crg_reg))
return dev_err_probe(host->dev, PTR_ERR(priv->crg_reg),
"failed to get CRG reg\n");
ret = of_property_read_u32_index(np, "hisilicon,sap-dll-reg", 1, &priv->sap_dll_offset);
if (ret)
return dev_err_probe(host->dev, ret, "failed to get sample DLL register offset\n");
host->priv = priv;
return 0;
}
static const struct dw_mci_drv_data hi3798mv200_data = {
.common_caps = MMC_CAP_CMD23,
.init = dw_mci_hi3798mv200_init,
.set_ios = dw_mci_hi3798mv200_set_ios,
.execute_tuning = dw_mci_hi3798mv200_execute_tuning_mix_mode,
};
static const struct of_device_id dw_mci_hi3798mv200_match[] = {
{ .compatible = "hisilicon,hi3798mv200-dw-mshc" },
{},
};
static int dw_mci_hi3798mv200_probe(struct platform_device *pdev)
{
return dw_mci_pltfm_register(pdev, &hi3798mv200_data);
}
static void dw_mci_hi3798mv200_remove(struct platform_device *pdev)
{
dw_mci_pltfm_remove(pdev);
}
MODULE_DEVICE_TABLE(of, dw_mci_hi3798mv200_match);
static struct platform_driver dw_mci_hi3798mv200_driver = {
.probe = dw_mci_hi3798mv200_probe,
.remove_new = dw_mci_hi3798mv200_remove,
.driver = {
.name = "dwmmc_hi3798mv200",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = dw_mci_hi3798mv200_match,
},
};
module_platform_driver(dw_mci_hi3798mv200_driver);
MODULE_DESCRIPTION("HiSilicon Hi3798MV200 Specific DW-MSHC Driver Extension");
MODULE_LICENSE("GPL");
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