u-boot/drivers/mmc/rockchip_sdhci.c
Stefan Herbrechtsmeier 6d0e34bf4e mmc: sdhci: Distinguish between base clock and maximum peripheral frequency
The sdhci controller assumes that the base clock frequency is fully supported by
the peripheral and doesn't support hardware limitations. The Linux kernel
distinguishes between base clock (max_clk) of the host controller and maximum
frequency (f_max) of the card interface. Use the same differentiation and allow
the platform to constrain the peripheral interface.

Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
2017-01-23 15:37:42 +09:00

99 lines
2.2 KiB
C

/*
* (C) Copyright 2016 Fuzhou Rockchip Electronics Co., Ltd
*
* Rockchip SD Host Controller Interface
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <fdtdec.h>
#include <libfdt.h>
#include <malloc.h>
#include <sdhci.h>
#include <clk.h>
DECLARE_GLOBAL_DATA_PTR;
/* 400KHz is max freq for card ID etc. Use that as min */
#define EMMC_MIN_FREQ 400000
struct rockchip_sdhc_plat {
struct mmc_config cfg;
struct mmc mmc;
};
struct rockchip_sdhc {
struct sdhci_host host;
void *base;
};
static int arasan_sdhci_probe(struct udevice *dev)
{
struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
struct rockchip_sdhc_plat *plat = dev_get_platdata(dev);
struct rockchip_sdhc *prv = dev_get_priv(dev);
struct sdhci_host *host = &prv->host;
int max_frequency, ret;
struct clk clk;
max_frequency = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
"max-frequency", 0);
ret = clk_get_by_index(dev, 0, &clk);
if (!ret) {
ret = clk_set_rate(&clk, max_frequency);
if (IS_ERR_VALUE(ret))
printf("%s clk set rate fail!\n", __func__);
} else {
printf("%s fail to get clk\n", __func__);
}
host->quirks = SDHCI_QUIRK_WAIT_SEND_CMD;
host->max_clk = max_frequency;
ret = sdhci_setup_cfg(&plat->cfg, host, 0, EMMC_MIN_FREQ);
host->mmc = &plat->mmc;
if (ret)
return ret;
host->mmc->priv = &prv->host;
host->mmc->dev = dev;
upriv->mmc = host->mmc;
return sdhci_probe(dev);
}
static int arasan_sdhci_ofdata_to_platdata(struct udevice *dev)
{
struct sdhci_host *host = dev_get_priv(dev);
host->name = dev->name;
host->ioaddr = dev_get_addr_ptr(dev);
return 0;
}
static int rockchip_sdhci_bind(struct udevice *dev)
{
struct rockchip_sdhc_plat *plat = dev_get_platdata(dev);
return sdhci_bind(dev, &plat->mmc, &plat->cfg);
}
static const struct udevice_id arasan_sdhci_ids[] = {
{ .compatible = "arasan,sdhci-5.1" },
{ }
};
U_BOOT_DRIVER(arasan_sdhci_drv) = {
.name = "arasan_sdhci",
.id = UCLASS_MMC,
.of_match = arasan_sdhci_ids,
.ofdata_to_platdata = arasan_sdhci_ofdata_to_platdata,
.ops = &sdhci_ops,
.bind = rockchip_sdhci_bind,
.probe = arasan_sdhci_probe,
.priv_auto_alloc_size = sizeof(struct rockchip_sdhc),
.platdata_auto_alloc_size = sizeof(struct rockchip_sdhc_plat),
};