u-boot/drivers/mmc/nexell_dw_mmc.c
Siew Chin Lim d456dfbaa0 mmc: dwmmc: Change designware MMC 'clksel' callback function to return status
Change 'clksel' callback function to allow the code to return a
status.

This patch is a preparation for enabling Arm-Trusted-Firmware (ATF)
in Intel SoC FPGA. This patch does not change functionality.

When using Arm-Trusted-Firmware (ATF) in Intel SoC FPGA, the MMC clock
related register is secure register which is required to be written
via SMC/PCSI call. It is possible that U-Boot fail to write the
register if there is unexpected error between U-Boot and ATF.
As a result, there maybe signal integrity on MMC connection due to
clock. So, the code should reports error to user when 'clksel' fail.

Signed-off-by: Siew Chin Lim <elly.siew.chin.lim@intel.com>
2021-01-15 17:48:36 +08:00

239 lines
6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2016 Nexell
* Youngbok, Park <park@nexell.co.kr>
*
* (C) Copyright 2019 Stefan Bosch <stefan_b@posteo.net>
*/
#include <common.h>
#include <dm.h>
#include <dt-structs.h>
#include <dwmmc.h>
#include <log.h>
#include <syscon.h>
#include <asm/arch/reset.h>
#include <asm/arch/clk.h>
#define DWMCI_CLKSEL 0x09C
#define DWMCI_SHIFT_0 0x0
#define DWMCI_SHIFT_1 0x1
#define DWMCI_SHIFT_2 0x2
#define DWMCI_SHIFT_3 0x3
#define DWMCI_SET_SAMPLE_CLK(x) (x)
#define DWMCI_SET_DRV_CLK(x) ((x) << 16)
#define DWMCI_SET_DIV_RATIO(x) ((x) << 24)
#define DWMCI_CLKCTRL 0x114
#define NX_MMC_CLK_DELAY(x, y, a, b) ((((x) & 0xFF) << 0) |\
(((y) & 0x03) << 16) |\
(((a) & 0xFF) << 8) |\
(((b) & 0x03) << 24))
struct nexell_mmc_plat {
struct mmc_config cfg;
struct mmc mmc;
};
struct nexell_dwmmc_priv {
struct clk *clk;
struct dwmci_host host;
int fifo_size;
bool fifo_mode;
int frequency;
u32 min_freq;
u32 max_freq;
int d_delay;
int d_shift;
int s_delay;
int s_shift;
bool mmcboost;
};
struct clk *clk_get(const char *id);
static int nx_dw_mmc_clksel(struct dwmci_host *host)
{
/* host->priv is pointer to "struct udevice" */
struct nexell_dwmmc_priv *priv = dev_get_priv(host->priv);
u32 val;
if (priv->mmcboost)
val = DWMCI_SET_SAMPLE_CLK(DWMCI_SHIFT_0) |
DWMCI_SET_DRV_CLK(DWMCI_SHIFT_0) | DWMCI_SET_DIV_RATIO(1);
else
val = DWMCI_SET_SAMPLE_CLK(DWMCI_SHIFT_0) |
DWMCI_SET_DRV_CLK(DWMCI_SHIFT_0) | DWMCI_SET_DIV_RATIO(3);
dwmci_writel(host, DWMCI_CLKSEL, val);
return 0;
}
static void nx_dw_mmc_reset(int ch)
{
int rst_id = RESET_ID_SDMMC0 + ch;
nx_rstcon_setrst(rst_id, 0);
nx_rstcon_setrst(rst_id, 1);
}
static void nx_dw_mmc_clk_delay(struct udevice *dev)
{
unsigned int delay;
struct nexell_dwmmc_priv *priv = dev_get_priv(dev);
struct dwmci_host *host = &priv->host;
delay = NX_MMC_CLK_DELAY(priv->d_delay,
priv->d_shift, priv->s_delay, priv->s_shift);
writel(delay, (host->ioaddr + DWMCI_CLKCTRL));
debug("%s: Values set: d_delay==%d, d_shift==%d, s_delay==%d, "
"s_shift==%d\n", __func__, priv->d_delay, priv->d_shift,
priv->s_delay, priv->s_shift);
}
static unsigned int nx_dw_mmc_get_clk(struct dwmci_host *host, uint freq)
{
struct clk *clk;
struct udevice *dev = host->priv;
struct nexell_dwmmc_priv *priv = dev_get_priv(dev);
int index = host->dev_index;
char name[50] = { 0, };
clk = priv->clk;
if (!clk) {
sprintf(name, "%s.%d", DEV_NAME_SDHC, index);
clk = clk_get((const char *)name);
if (!clk)
return 0;
priv->clk = clk;
}
return clk_get_rate(clk) / 2;
}
static unsigned long nx_dw_mmc_set_clk(struct dwmci_host *host,
unsigned int rate)
{
struct clk *clk;
char name[50] = { 0, };
struct udevice *dev = host->priv;
struct nexell_dwmmc_priv *priv = dev_get_priv(dev);
int index = host->dev_index;
clk = priv->clk;
if (!clk) {
sprintf(name, "%s.%d", DEV_NAME_SDHC, index);
clk = clk_get((const char *)name);
if (!clk) {
debug("%s: clk_get(\"%s\") failed!\n", __func__, name);
return 0;
}
priv->clk = clk;
}
clk_disable(clk);
rate = clk_set_rate(clk, rate);
clk_enable(clk);
return rate;
}
static int nexell_dwmmc_of_to_plat(struct udevice *dev)
{
struct nexell_dwmmc_priv *priv = dev_get_priv(dev);
struct dwmci_host *host = &priv->host;
int val = -1;
debug("%s\n", __func__);
host->name = dev->name;
host->ioaddr = dev_read_addr_ptr(dev);
host->buswidth = dev_read_u32_default(dev, "bus-width", 4);
host->get_mmc_clk = nx_dw_mmc_get_clk;
host->clksel = nx_dw_mmc_clksel;
host->priv = dev;
val = dev_read_u32_default(dev, "index", -1);
if (val < 0 || val > 2) {
debug(" 'index' missing/invalid!\n");
return -EINVAL;
}
host->dev_index = val;
priv->fifo_size = dev_read_u32_default(dev, "fifo-size", 0x20);
priv->fifo_mode = dev_read_bool(dev, "fifo-mode");
priv->frequency = dev_read_u32_default(dev, "frequency", 50000000);
priv->max_freq = dev_read_u32_default(dev, "max-frequency", 50000000);
priv->min_freq = 400000; /* 400 kHz */
priv->d_delay = dev_read_u32_default(dev, "drive_dly", 0);
priv->d_shift = dev_read_u32_default(dev, "drive_shift", 3);
priv->s_delay = dev_read_u32_default(dev, "sample_dly", 0);
priv->s_shift = dev_read_u32_default(dev, "sample_shift", 2);
priv->mmcboost = dev_read_u32_default(dev, "mmcboost", 0);
debug(" index==%d, name==%s, ioaddr==0x%08x\n",
host->dev_index, host->name, (u32)host->ioaddr);
return 0;
}
static int nexell_dwmmc_probe(struct udevice *dev)
{
struct nexell_mmc_plat *plat = dev_get_plat(dev);
struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
struct nexell_dwmmc_priv *priv = dev_get_priv(dev);
struct dwmci_host *host = &priv->host;
struct udevice *pwr_dev __maybe_unused;
host->fifoth_val = MSIZE(0x2) |
RX_WMARK(priv->fifo_size / 2 - 1) |
TX_WMARK(priv->fifo_size / 2);
host->fifo_mode = priv->fifo_mode;
dwmci_setup_cfg(&plat->cfg, host, priv->max_freq, priv->min_freq);
host->mmc = &plat->mmc;
host->mmc->priv = &priv->host;
host->mmc->dev = dev;
upriv->mmc = host->mmc;
if (nx_dw_mmc_set_clk(host, priv->frequency * 4) !=
priv->frequency * 4) {
debug("%s: nx_dw_mmc_set_clk(host, %d) failed!\n",
__func__, priv->frequency * 4);
return -EIO;
}
debug("%s: nx_dw_mmc_set_clk(host, %d) OK\n",
__func__, priv->frequency * 4);
nx_dw_mmc_reset(host->dev_index);
nx_dw_mmc_clk_delay(dev);
return dwmci_probe(dev);
}
static int nexell_dwmmc_bind(struct udevice *dev)
{
struct nexell_mmc_plat *plat = dev_get_plat(dev);
return dwmci_bind(dev, &plat->mmc, &plat->cfg);
}
static const struct udevice_id nexell_dwmmc_ids[] = {
{ .compatible = "nexell,nexell-dwmmc" },
{ }
};
U_BOOT_DRIVER(nexell_dwmmc_drv) = {
.name = "nexell_dwmmc",
.id = UCLASS_MMC,
.of_match = nexell_dwmmc_ids,
.of_to_plat = nexell_dwmmc_of_to_plat,
.ops = &dm_dwmci_ops,
.bind = nexell_dwmmc_bind,
.probe = nexell_dwmmc_probe,
.priv_auto = sizeof(struct nexell_dwmmc_priv),
.plat_auto = sizeof(struct nexell_mmc_plat),
};