linux/drivers/mmc/host/uniphier-sd.c
2019-09-13 13:57:37 +02:00

697 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// Copyright (C) 2017-2018 Socionext Inc.
// Author: Masahiro Yamada <yamada.masahiro@socionext.com>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/mfd/tmio.h>
#include <linux/mmc/host.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include "tmio_mmc.h"
#define UNIPHIER_SD_CLK_CTL_DIV1024 BIT(16)
#define UNIPHIER_SD_CLK_CTL_DIV1 BIT(10)
#define UNIPHIER_SD_CLKCTL_OFFEN BIT(9) // auto SDCLK stop
#define UNIPHIER_SD_CC_EXT_MODE 0x1b0
#define UNIPHIER_SD_CC_EXT_MODE_DMA BIT(1)
#define UNIPHIER_SD_HOST_MODE 0x1c8
#define UNIPHIER_SD_VOLT 0x1e4
#define UNIPHIER_SD_VOLT_MASK GENMASK(1, 0)
#define UNIPHIER_SD_VOLT_OFF 0
#define UNIPHIER_SD_VOLT_330 1 // 3.3V signal
#define UNIPHIER_SD_VOLT_180 2 // 1.8V signal
#define UNIPHIER_SD_DMA_MODE 0x410
#define UNIPHIER_SD_DMA_MODE_DIR_MASK GENMASK(17, 16)
#define UNIPHIER_SD_DMA_MODE_DIR_TO_DEV 0
#define UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV 1
#define UNIPHIER_SD_DMA_MODE_WIDTH_MASK GENMASK(5, 4)
#define UNIPHIER_SD_DMA_MODE_WIDTH_8 0
#define UNIPHIER_SD_DMA_MODE_WIDTH_16 1
#define UNIPHIER_SD_DMA_MODE_WIDTH_32 2
#define UNIPHIER_SD_DMA_MODE_WIDTH_64 3
#define UNIPHIER_SD_DMA_MODE_ADDR_INC BIT(0) // 1: inc, 0: fixed
#define UNIPHIER_SD_DMA_CTL 0x414
#define UNIPHIER_SD_DMA_CTL_START BIT(0) // start DMA (auto cleared)
#define UNIPHIER_SD_DMA_RST 0x418
#define UNIPHIER_SD_DMA_RST_CH1 BIT(9)
#define UNIPHIER_SD_DMA_RST_CH0 BIT(8)
#define UNIPHIER_SD_DMA_ADDR_L 0x440
#define UNIPHIER_SD_DMA_ADDR_H 0x444
/*
* IP is extended to support various features: built-in DMA engine,
* 1/1024 divisor, etc.
*/
#define UNIPHIER_SD_CAP_EXTENDED_IP BIT(0)
/* RX channel of the built-in DMA controller is broken (Pro5) */
#define UNIPHIER_SD_CAP_BROKEN_DMA_RX BIT(1)
struct uniphier_sd_priv {
struct tmio_mmc_data tmio_data;
struct pinctrl *pinctrl;
struct pinctrl_state *pinstate_default;
struct pinctrl_state *pinstate_uhs;
struct clk *clk;
struct reset_control *rst;
struct reset_control *rst_br;
struct reset_control *rst_hw;
struct dma_chan *chan;
enum dma_data_direction dma_dir;
unsigned long clk_rate;
unsigned long caps;
};
static void *uniphier_sd_priv(struct tmio_mmc_host *host)
{
return container_of(host->pdata, struct uniphier_sd_priv, tmio_data);
}
static void uniphier_sd_dma_endisable(struct tmio_mmc_host *host, int enable)
{
sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
}
/* external DMA engine */
static void uniphier_sd_external_dma_issue(unsigned long arg)
{
struct tmio_mmc_host *host = (void *)arg;
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
uniphier_sd_dma_endisable(host, 1);
dma_async_issue_pending(priv->chan);
}
static void uniphier_sd_external_dma_callback(void *param,
const struct dmaengine_result *result)
{
struct tmio_mmc_host *host = param;
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
unsigned long flags;
dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
priv->dma_dir);
spin_lock_irqsave(&host->lock, flags);
if (result->result == DMA_TRANS_NOERROR) {
/*
* When the external DMA engine is enabled, strangely enough,
* the DATAEND flag can be asserted even if the DMA engine has
* not been kicked yet. Enable the TMIO_STAT_DATAEND irq only
* after we make sure the DMA engine finishes the transfer,
* hence, in this callback.
*/
tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
} else {
host->data->error = -ETIMEDOUT;
tmio_mmc_do_data_irq(host);
}
spin_unlock_irqrestore(&host->lock, flags);
}
static void uniphier_sd_external_dma_start(struct tmio_mmc_host *host,
struct mmc_data *data)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
enum dma_transfer_direction dma_tx_dir;
struct dma_async_tx_descriptor *desc;
dma_cookie_t cookie;
int sg_len;
if (!priv->chan)
goto force_pio;
if (data->flags & MMC_DATA_READ) {
priv->dma_dir = DMA_FROM_DEVICE;
dma_tx_dir = DMA_DEV_TO_MEM;
} else {
priv->dma_dir = DMA_TO_DEVICE;
dma_tx_dir = DMA_MEM_TO_DEV;
}
sg_len = dma_map_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
priv->dma_dir);
if (sg_len == 0)
goto force_pio;
desc = dmaengine_prep_slave_sg(priv->chan, host->sg_ptr, sg_len,
dma_tx_dir, DMA_CTRL_ACK);
if (!desc)
goto unmap_sg;
desc->callback_result = uniphier_sd_external_dma_callback;
desc->callback_param = host;
cookie = dmaengine_submit(desc);
if (cookie < 0)
goto unmap_sg;
host->dma_on = true;
return;
unmap_sg:
dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
priv->dma_dir);
force_pio:
uniphier_sd_dma_endisable(host, 0);
}
static void uniphier_sd_external_dma_enable(struct tmio_mmc_host *host,
bool enable)
{
}
static void uniphier_sd_external_dma_request(struct tmio_mmc_host *host,
struct tmio_mmc_data *pdata)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
struct dma_chan *chan;
chan = dma_request_chan(mmc_dev(host->mmc), "rx-tx");
if (IS_ERR(chan)) {
dev_warn(mmc_dev(host->mmc),
"failed to request DMA channel. falling back to PIO\n");
return; /* just use PIO even for -EPROBE_DEFER */
}
/* this driver uses a single channel for both RX an TX */
priv->chan = chan;
host->chan_rx = chan;
host->chan_tx = chan;
tasklet_init(&host->dma_issue, uniphier_sd_external_dma_issue,
(unsigned long)host);
}
static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
if (priv->chan)
dma_release_channel(priv->chan);
}
static void uniphier_sd_external_dma_abort(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
uniphier_sd_dma_endisable(host, 0);
if (priv->chan)
dmaengine_terminate_sync(priv->chan);
}
static void uniphier_sd_external_dma_dataend(struct tmio_mmc_host *host)
{
uniphier_sd_dma_endisable(host, 0);
tmio_mmc_do_data_irq(host);
}
static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
.start = uniphier_sd_external_dma_start,
.enable = uniphier_sd_external_dma_enable,
.request = uniphier_sd_external_dma_request,
.release = uniphier_sd_external_dma_release,
.abort = uniphier_sd_external_dma_abort,
.dataend = uniphier_sd_external_dma_dataend,
};
static void uniphier_sd_internal_dma_issue(unsigned long arg)
{
struct tmio_mmc_host *host = (void *)arg;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
spin_unlock_irqrestore(&host->lock, flags);
uniphier_sd_dma_endisable(host, 1);
writel(UNIPHIER_SD_DMA_CTL_START, host->ctl + UNIPHIER_SD_DMA_CTL);
}
static void uniphier_sd_internal_dma_start(struct tmio_mmc_host *host,
struct mmc_data *data)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
struct scatterlist *sg = host->sg_ptr;
dma_addr_t dma_addr;
unsigned int dma_mode_dir;
u32 dma_mode;
int sg_len;
if ((data->flags & MMC_DATA_READ) && !host->chan_rx)
goto force_pio;
if (WARN_ON(host->sg_len != 1))
goto force_pio;
if (!IS_ALIGNED(sg->offset, 8))
goto force_pio;
if (data->flags & MMC_DATA_READ) {
priv->dma_dir = DMA_FROM_DEVICE;
dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV;
} else {
priv->dma_dir = DMA_TO_DEVICE;
dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_TO_DEV;
}
sg_len = dma_map_sg(mmc_dev(host->mmc), sg, 1, priv->dma_dir);
if (sg_len == 0)
goto force_pio;
dma_mode = FIELD_PREP(UNIPHIER_SD_DMA_MODE_DIR_MASK, dma_mode_dir);
dma_mode |= FIELD_PREP(UNIPHIER_SD_DMA_MODE_WIDTH_MASK,
UNIPHIER_SD_DMA_MODE_WIDTH_64);
dma_mode |= UNIPHIER_SD_DMA_MODE_ADDR_INC;
writel(dma_mode, host->ctl + UNIPHIER_SD_DMA_MODE);
dma_addr = sg_dma_address(data->sg);
writel(lower_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_L);
writel(upper_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_H);
host->dma_on = true;
return;
force_pio:
uniphier_sd_dma_endisable(host, 0);
}
static void uniphier_sd_internal_dma_enable(struct tmio_mmc_host *host,
bool enable)
{
}
static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
struct tmio_mmc_data *pdata)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
/*
* Due to a hardware bug, Pro5 cannot use DMA for RX.
* We can still use DMA for TX, but PIO for RX.
*/
if (!(priv->caps & UNIPHIER_SD_CAP_BROKEN_DMA_RX))
host->chan_rx = (void *)0xdeadbeaf;
host->chan_tx = (void *)0xdeadbeaf;
tasklet_init(&host->dma_issue, uniphier_sd_internal_dma_issue,
(unsigned long)host);
}
static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
{
/* Each value is set to zero to assume "disabling" each DMA */
host->chan_rx = NULL;
host->chan_tx = NULL;
}
static void uniphier_sd_internal_dma_abort(struct tmio_mmc_host *host)
{
u32 tmp;
uniphier_sd_dma_endisable(host, 0);
tmp = readl(host->ctl + UNIPHIER_SD_DMA_RST);
tmp &= ~(UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0);
writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
tmp |= UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0;
writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
}
static void uniphier_sd_internal_dma_dataend(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
uniphier_sd_dma_endisable(host, 0);
dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, 1, priv->dma_dir);
tmio_mmc_do_data_irq(host);
}
static const struct tmio_mmc_dma_ops uniphier_sd_internal_dma_ops = {
.start = uniphier_sd_internal_dma_start,
.enable = uniphier_sd_internal_dma_enable,
.request = uniphier_sd_internal_dma_request,
.release = uniphier_sd_internal_dma_release,
.abort = uniphier_sd_internal_dma_abort,
.dataend = uniphier_sd_internal_dma_dataend,
};
static int uniphier_sd_clk_enable(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
struct mmc_host *mmc = host->mmc;
int ret;
ret = clk_prepare_enable(priv->clk);
if (ret)
return ret;
ret = clk_set_rate(priv->clk, ULONG_MAX);
if (ret)
goto disable_clk;
priv->clk_rate = clk_get_rate(priv->clk);
/* If max-frequency property is set, use it. */
if (!mmc->f_max)
mmc->f_max = priv->clk_rate;
/*
* 1/512 is the finest divisor in the original IP. Newer versions
* also supports 1/1024 divisor. (UniPhier-specific extension)
*/
if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
mmc->f_min = priv->clk_rate / 1024;
else
mmc->f_min = priv->clk_rate / 512;
ret = reset_control_deassert(priv->rst);
if (ret)
goto disable_clk;
ret = reset_control_deassert(priv->rst_br);
if (ret)
goto assert_rst;
return 0;
assert_rst:
reset_control_assert(priv->rst);
disable_clk:
clk_disable_unprepare(priv->clk);
return ret;
}
static void uniphier_sd_clk_disable(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
reset_control_assert(priv->rst_br);
reset_control_assert(priv->rst);
clk_disable_unprepare(priv->clk);
}
static void uniphier_sd_hw_reset(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
reset_control_assert(priv->rst_hw);
/* For eMMC, minimum is 1us but give it 9us for good measure */
udelay(9);
reset_control_deassert(priv->rst_hw);
/* For eMMC, minimum is 200us but give it 300us for good measure */
usleep_range(300, 1000);
}
static void uniphier_sd_set_clock(struct tmio_mmc_host *host,
unsigned int clock)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
unsigned long divisor;
u32 tmp;
tmp = readl(host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
/* stop the clock before changing its rate to avoid a glitch signal */
tmp &= ~CLK_CTL_SCLKEN;
writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
if (clock == 0)
return;
tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1024;
tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1;
tmp &= ~CLK_CTL_DIV_MASK;
divisor = priv->clk_rate / clock;
/*
* In the original IP, bit[7:0] represents the divisor.
* bit7 set: 1/512, ... bit0 set:1/4, all bits clear: 1/2
*
* The IP does not define a way to achieve 1/1. For UniPhier variants,
* bit10 is used for 1/1. Newer versions of UniPhier variants use
* bit16 for 1/1024.
*/
if (divisor <= 1)
tmp |= UNIPHIER_SD_CLK_CTL_DIV1;
else if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP && divisor > 512)
tmp |= UNIPHIER_SD_CLK_CTL_DIV1024;
else
tmp |= roundup_pow_of_two(divisor) >> 2;
writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
tmp |= CLK_CTL_SCLKEN;
writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
}
static void uniphier_sd_host_init(struct tmio_mmc_host *host)
{
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
u32 val;
/*
* Connected to 32bit AXI.
* This register holds settings for SoC-specific internal bus
* connection. What is worse, the register spec was changed,
* breaking the backward compatibility. Write an appropriate
* value depending on a flag associated with a compatible string.
*/
if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
val = 0x00000101;
else
val = 0x00000000;
writel(val, host->ctl + UNIPHIER_SD_HOST_MODE);
val = 0;
/*
* If supported, the controller can automatically
* enable/disable the clock line to the card.
*/
if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
val |= UNIPHIER_SD_CLKCTL_OFFEN;
writel(val, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
}
static int uniphier_sd_start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
struct pinctrl_state *pinstate;
u32 val, tmp;
switch (ios->signal_voltage) {
case MMC_SIGNAL_VOLTAGE_330:
val = UNIPHIER_SD_VOLT_330;
pinstate = priv->pinstate_default;
break;
case MMC_SIGNAL_VOLTAGE_180:
val = UNIPHIER_SD_VOLT_180;
pinstate = priv->pinstate_uhs;
break;
default:
return -ENOTSUPP;
}
tmp = readl(host->ctl + UNIPHIER_SD_VOLT);
tmp &= ~UNIPHIER_SD_VOLT_MASK;
tmp |= FIELD_PREP(UNIPHIER_SD_VOLT_MASK, val);
writel(tmp, host->ctl + UNIPHIER_SD_VOLT);
pinctrl_select_state(priv->pinctrl, pinstate);
return 0;
}
static int uniphier_sd_uhs_init(struct tmio_mmc_host *host,
struct uniphier_sd_priv *priv)
{
priv->pinctrl = devm_pinctrl_get(mmc_dev(host->mmc));
if (IS_ERR(priv->pinctrl))
return PTR_ERR(priv->pinctrl);
priv->pinstate_default = pinctrl_lookup_state(priv->pinctrl,
PINCTRL_STATE_DEFAULT);
if (IS_ERR(priv->pinstate_default))
return PTR_ERR(priv->pinstate_default);
priv->pinstate_uhs = pinctrl_lookup_state(priv->pinctrl, "uhs");
if (IS_ERR(priv->pinstate_uhs))
return PTR_ERR(priv->pinstate_uhs);
host->ops.start_signal_voltage_switch =
uniphier_sd_start_signal_voltage_switch;
return 0;
}
static int uniphier_sd_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct uniphier_sd_priv *priv;
struct tmio_mmc_data *tmio_data;
struct tmio_mmc_host *host;
int irq, ret;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->caps = (unsigned long)of_device_get_match_data(dev);
priv->clk = devm_clk_get(dev, NULL);
if (IS_ERR(priv->clk)) {
dev_err(dev, "failed to get clock\n");
return PTR_ERR(priv->clk);
}
priv->rst = devm_reset_control_get_shared(dev, "host");
if (IS_ERR(priv->rst)) {
dev_err(dev, "failed to get host reset\n");
return PTR_ERR(priv->rst);
}
/* old version has one more reset */
if (!(priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)) {
priv->rst_br = devm_reset_control_get_shared(dev, "bridge");
if (IS_ERR(priv->rst_br)) {
dev_err(dev, "failed to get bridge reset\n");
return PTR_ERR(priv->rst_br);
}
}
tmio_data = &priv->tmio_data;
tmio_data->flags |= TMIO_MMC_32BIT_DATA_PORT;
host = tmio_mmc_host_alloc(pdev, tmio_data);
if (IS_ERR(host))
return PTR_ERR(host);
if (host->mmc->caps & MMC_CAP_HW_RESET) {
priv->rst_hw = devm_reset_control_get_exclusive(dev, "hw");
if (IS_ERR(priv->rst_hw)) {
dev_err(dev, "failed to get hw reset\n");
ret = PTR_ERR(priv->rst_hw);
goto free_host;
}
host->hw_reset = uniphier_sd_hw_reset;
}
if (host->mmc->caps & MMC_CAP_UHS) {
ret = uniphier_sd_uhs_init(host, priv);
if (ret) {
dev_warn(dev,
"failed to setup UHS (error %d). Disabling UHS.",
ret);
host->mmc->caps &= ~MMC_CAP_UHS;
}
}
ret = devm_request_irq(dev, irq, tmio_mmc_irq, IRQF_SHARED,
dev_name(dev), host);
if (ret)
goto free_host;
if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
host->dma_ops = &uniphier_sd_internal_dma_ops;
else
host->dma_ops = &uniphier_sd_external_dma_ops;
host->bus_shift = 1;
host->clk_enable = uniphier_sd_clk_enable;
host->clk_disable = uniphier_sd_clk_disable;
host->set_clock = uniphier_sd_set_clock;
ret = uniphier_sd_clk_enable(host);
if (ret)
goto free_host;
uniphier_sd_host_init(host);
tmio_data->ocr_mask = MMC_VDD_32_33 | MMC_VDD_33_34;
if (host->mmc->caps & MMC_CAP_UHS)
tmio_data->ocr_mask |= MMC_VDD_165_195;
tmio_data->max_segs = 1;
tmio_data->max_blk_count = U16_MAX;
ret = tmio_mmc_host_probe(host);
if (ret)
goto free_host;
return 0;
free_host:
tmio_mmc_host_free(host);
return ret;
}
static int uniphier_sd_remove(struct platform_device *pdev)
{
struct tmio_mmc_host *host = platform_get_drvdata(pdev);
tmio_mmc_host_remove(host);
uniphier_sd_clk_disable(host);
return 0;
}
static const struct of_device_id uniphier_sd_match[] = {
{
.compatible = "socionext,uniphier-sd-v2.91",
},
{
.compatible = "socionext,uniphier-sd-v3.1",
.data = (void *)(UNIPHIER_SD_CAP_EXTENDED_IP |
UNIPHIER_SD_CAP_BROKEN_DMA_RX),
},
{
.compatible = "socionext,uniphier-sd-v3.1.1",
.data = (void *)UNIPHIER_SD_CAP_EXTENDED_IP,
},
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, uniphier_sd_match);
static struct platform_driver uniphier_sd_driver = {
.probe = uniphier_sd_probe,
.remove = uniphier_sd_remove,
.driver = {
.name = "uniphier-sd",
.of_match_table = uniphier_sd_match,
},
};
module_platform_driver(uniphier_sd_driver);
MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
MODULE_DESCRIPTION("UniPhier SD/eMMC host controller driver");
MODULE_LICENSE("GPL v2");