mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 08:14:15 +08:00
c8b850f0f0
Before, we used syscon to achieve tuning, but the actual measurement showed little effect, so the tuning implementation was modified here, and it was realized by reading and writing the UHS_REG_EXT register. Signed-off-by: William Qiu <william.qiu@starfivetech.com> Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Link: https://lore.kernel.org/r/20230922062834.39212-3-william.qiu@starfivetech.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
130 lines
3.4 KiB
C
130 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* StarFive Designware Mobile Storage Host Controller Driver
|
|
*
|
|
* Copyright (c) 2022 StarFive Technology Co., Ltd.
|
|
*/
|
|
|
|
#include <linux/bitfield.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/delay.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 ALL_INT_CLR 0x1ffff
|
|
#define MAX_DELAY_CHAIN 32
|
|
|
|
#define STARFIVE_SMPL_PHASE GENMASK(20, 16)
|
|
|
|
static void dw_mci_starfive_set_ios(struct dw_mci *host, struct mmc_ios *ios)
|
|
{
|
|
int ret;
|
|
unsigned int clock;
|
|
|
|
if (ios->timing == MMC_TIMING_MMC_DDR52 || ios->timing == MMC_TIMING_UHS_DDR50) {
|
|
clock = (ios->clock > 50000000 && ios->clock <= 52000000) ? 100000000 : ios->clock;
|
|
ret = clk_set_rate(host->ciu_clk, clock);
|
|
if (ret)
|
|
dev_dbg(host->dev, "Use an external frequency divider %uHz\n", ios->clock);
|
|
host->bus_hz = clk_get_rate(host->ciu_clk);
|
|
} else {
|
|
dev_dbg(host->dev, "Using the internal divider\n");
|
|
}
|
|
}
|
|
|
|
static void dw_mci_starfive_set_sample_phase(struct dw_mci *host, u32 smpl_phase)
|
|
{
|
|
/* change driver phase and sample phase */
|
|
u32 reg_value = mci_readl(host, UHS_REG_EXT);
|
|
|
|
/* In UHS_REG_EXT, only 5 bits valid in DRV_PHASE and SMPL_PHASE */
|
|
reg_value &= ~STARFIVE_SMPL_PHASE;
|
|
reg_value |= FIELD_PREP(STARFIVE_SMPL_PHASE, smpl_phase);
|
|
mci_writel(host, UHS_REG_EXT, reg_value);
|
|
|
|
/* We should delay 1ms wait for timing setting finished. */
|
|
mdelay(1);
|
|
}
|
|
|
|
static int dw_mci_starfive_execute_tuning(struct dw_mci_slot *slot,
|
|
u32 opcode)
|
|
{
|
|
static const int grade = MAX_DELAY_CHAIN;
|
|
struct dw_mci *host = slot->host;
|
|
int smpl_phase, smpl_raise = -1, smpl_fall = -1;
|
|
int ret;
|
|
|
|
for (smpl_phase = 0; smpl_phase < grade; smpl_phase++) {
|
|
dw_mci_starfive_set_sample_phase(host, smpl_phase);
|
|
mci_writel(host, RINTSTS, ALL_INT_CLR);
|
|
|
|
ret = mmc_send_tuning(slot->mmc, opcode, NULL);
|
|
|
|
if (!ret && smpl_raise < 0) {
|
|
smpl_raise = smpl_phase;
|
|
} else if (ret && smpl_raise >= 0) {
|
|
smpl_fall = smpl_phase - 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (smpl_phase >= grade)
|
|
smpl_fall = grade - 1;
|
|
|
|
if (smpl_raise < 0) {
|
|
smpl_phase = 0;
|
|
dev_err(host->dev, "No valid delay chain! use default\n");
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
smpl_phase = (smpl_raise + smpl_fall) / 2;
|
|
dev_dbg(host->dev, "Found valid delay chain! use it [delay=%d]\n", smpl_phase);
|
|
ret = 0;
|
|
|
|
out:
|
|
dw_mci_starfive_set_sample_phase(host, smpl_phase);
|
|
mci_writel(host, RINTSTS, ALL_INT_CLR);
|
|
return ret;
|
|
}
|
|
|
|
static const struct dw_mci_drv_data starfive_data = {
|
|
.common_caps = MMC_CAP_CMD23,
|
|
.set_ios = dw_mci_starfive_set_ios,
|
|
.execute_tuning = dw_mci_starfive_execute_tuning,
|
|
};
|
|
|
|
static const struct of_device_id dw_mci_starfive_match[] = {
|
|
{ .compatible = "starfive,jh7110-mmc",
|
|
.data = &starfive_data },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, dw_mci_starfive_match);
|
|
|
|
static int dw_mci_starfive_probe(struct platform_device *pdev)
|
|
{
|
|
return dw_mci_pltfm_register(pdev, &starfive_data);
|
|
}
|
|
|
|
static struct platform_driver dw_mci_starfive_driver = {
|
|
.probe = dw_mci_starfive_probe,
|
|
.remove_new = dw_mci_pltfm_remove,
|
|
.driver = {
|
|
.name = "dwmmc_starfive",
|
|
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
|
|
.of_match_table = dw_mci_starfive_match,
|
|
},
|
|
};
|
|
module_platform_driver(dw_mci_starfive_driver);
|
|
|
|
MODULE_DESCRIPTION("StarFive JH7110 Specific DW-MSHC Driver Extension");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:dwmmc_starfive");
|