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linux-sg2042/drivers/mmc/host/meson-gx-mmc.c

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/*
* Amlogic SD/eMMC driver for the GX/S905 family SoCs
*
* Copyright (c) 2016 BayLibre, SAS.
* Author: Kevin Hilman <khilman@baylibre.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
* The full GNU General Public License is included in this distribution
* in the file called COPYING.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#include <linux/dma-mapping.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/interrupt.h>
#include <linux/bitfield.h>
#include <linux/pinctrl/consumer.h>
#define DRIVER_NAME "meson-gx-mmc"
#define SD_EMMC_CLOCK 0x0
#define CLK_DIV_MASK GENMASK(5, 0)
#define CLK_SRC_MASK GENMASK(7, 6)
#define CLK_CORE_PHASE_MASK GENMASK(9, 8)
#define CLK_TX_PHASE_MASK GENMASK(11, 10)
#define CLK_RX_PHASE_MASK GENMASK(13, 12)
#define CLK_V2_TX_DELAY_MASK GENMASK(19, 16)
#define CLK_V2_RX_DELAY_MASK GENMASK(23, 20)
#define CLK_V2_ALWAYS_ON BIT(24)
#define CLK_V3_TX_DELAY_MASK GENMASK(21, 16)
#define CLK_V3_RX_DELAY_MASK GENMASK(27, 22)
#define CLK_V3_ALWAYS_ON BIT(28)
#define CLK_DELAY_STEP_PS 200
#define CLK_PHASE_STEP 30
#define CLK_PHASE_POINT_NUM (360 / CLK_PHASE_STEP)
#define CLK_TX_DELAY_MASK(h) (h->data->tx_delay_mask)
#define CLK_RX_DELAY_MASK(h) (h->data->rx_delay_mask)
#define CLK_ALWAYS_ON(h) (h->data->always_on)
#define SD_EMMC_DELAY 0x4
#define SD_EMMC_ADJUST 0x8
#define SD_EMMC_DELAY1 0x4
#define SD_EMMC_DELAY2 0x8
#define SD_EMMC_V3_ADJUST 0xc
#define SD_EMMC_CALOUT 0x10
#define SD_EMMC_START 0x40
#define START_DESC_INIT BIT(0)
#define START_DESC_BUSY BIT(1)
#define START_DESC_ADDR_MASK GENMASK(31, 2)
#define SD_EMMC_CFG 0x44
#define CFG_BUS_WIDTH_MASK GENMASK(1, 0)
#define CFG_BUS_WIDTH_1 0x0
#define CFG_BUS_WIDTH_4 0x1
#define CFG_BUS_WIDTH_8 0x2
#define CFG_DDR BIT(2)
#define CFG_BLK_LEN_MASK GENMASK(7, 4)
#define CFG_RESP_TIMEOUT_MASK GENMASK(11, 8)
#define CFG_RC_CC_MASK GENMASK(15, 12)
#define CFG_STOP_CLOCK BIT(22)
#define CFG_CLK_ALWAYS_ON BIT(18)
#define CFG_CHK_DS BIT(20)
#define CFG_AUTO_CLK BIT(23)
#define SD_EMMC_STATUS 0x48
#define STATUS_BUSY BIT(31)
#define STATUS_DATI GENMASK(23, 16)
#define SD_EMMC_IRQ_EN 0x4c
#define IRQ_RXD_ERR_MASK GENMASK(7, 0)
#define IRQ_TXD_ERR BIT(8)
#define IRQ_DESC_ERR BIT(9)
#define IRQ_RESP_ERR BIT(10)
#define IRQ_CRC_ERR \
(IRQ_RXD_ERR_MASK | IRQ_TXD_ERR | IRQ_DESC_ERR | IRQ_RESP_ERR)
#define IRQ_RESP_TIMEOUT BIT(11)
#define IRQ_DESC_TIMEOUT BIT(12)
#define IRQ_TIMEOUTS \
(IRQ_RESP_TIMEOUT | IRQ_DESC_TIMEOUT)
#define IRQ_END_OF_CHAIN BIT(13)
#define IRQ_RESP_STATUS BIT(14)
#define IRQ_SDIO BIT(15)
#define IRQ_EN_MASK \
(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN | IRQ_RESP_STATUS |\
IRQ_SDIO)
#define SD_EMMC_CMD_CFG 0x50
#define SD_EMMC_CMD_ARG 0x54
#define SD_EMMC_CMD_DAT 0x58
#define SD_EMMC_CMD_RSP 0x5c
#define SD_EMMC_CMD_RSP1 0x60
#define SD_EMMC_CMD_RSP2 0x64
#define SD_EMMC_CMD_RSP3 0x68
#define SD_EMMC_RXD 0x94
#define SD_EMMC_TXD 0x94
#define SD_EMMC_LAST_REG SD_EMMC_TXD
#define SD_EMMC_CFG_BLK_SIZE 512 /* internal buffer max: 512 bytes */
#define SD_EMMC_CFG_RESP_TIMEOUT 256 /* in clock cycles */
#define SD_EMMC_CMD_TIMEOUT 1024 /* in ms */
#define SD_EMMC_CMD_TIMEOUT_DATA 4096 /* in ms */
#define SD_EMMC_CFG_CMD_GAP 16 /* in clock cycles */
#define SD_EMMC_DESC_BUF_LEN PAGE_SIZE
#define SD_EMMC_PRE_REQ_DONE BIT(0)
#define SD_EMMC_DESC_CHAIN_MODE BIT(1)
#define MUX_CLK_NUM_PARENTS 2
struct meson_mmc_data {
unsigned int tx_delay_mask;
unsigned int rx_delay_mask;
unsigned int always_on;
};
struct sd_emmc_desc {
u32 cmd_cfg;
u32 cmd_arg;
u32 cmd_data;
u32 cmd_resp;
};
struct meson_host {
struct device *dev;
struct meson_mmc_data *data;
struct mmc_host *mmc;
struct mmc_command *cmd;
spinlock_t lock;
void __iomem *regs;
struct clk *core_clk;
struct clk *mmc_clk;
struct clk *rx_clk;
struct clk *tx_clk;
unsigned long req_rate;
struct pinctrl *pinctrl;
struct pinctrl_state *pins_default;
struct pinctrl_state *pins_clk_gate;
unsigned int bounce_buf_size;
void *bounce_buf;
dma_addr_t bounce_dma_addr;
struct sd_emmc_desc *descs;
dma_addr_t descs_dma_addr;
bool vqmmc_enabled;
};
#define CMD_CFG_LENGTH_MASK GENMASK(8, 0)
#define CMD_CFG_BLOCK_MODE BIT(9)
#define CMD_CFG_R1B BIT(10)
#define CMD_CFG_END_OF_CHAIN BIT(11)
#define CMD_CFG_TIMEOUT_MASK GENMASK(15, 12)
#define CMD_CFG_NO_RESP BIT(16)
#define CMD_CFG_NO_CMD BIT(17)
#define CMD_CFG_DATA_IO BIT(18)
#define CMD_CFG_DATA_WR BIT(19)
#define CMD_CFG_RESP_NOCRC BIT(20)
#define CMD_CFG_RESP_128 BIT(21)
#define CMD_CFG_RESP_NUM BIT(22)
#define CMD_CFG_DATA_NUM BIT(23)
#define CMD_CFG_CMD_INDEX_MASK GENMASK(29, 24)
#define CMD_CFG_ERROR BIT(30)
#define CMD_CFG_OWNER BIT(31)
#define CMD_DATA_MASK GENMASK(31, 2)
#define CMD_DATA_BIG_ENDIAN BIT(1)
#define CMD_DATA_SRAM BIT(0)
#define CMD_RESP_MASK GENMASK(31, 1)
#define CMD_RESP_SRAM BIT(0)
struct meson_mmc_phase {
struct clk_hw hw;
void __iomem *reg;
unsigned long phase_mask;
unsigned long delay_mask;
unsigned int delay_step_ps;
};
#define to_meson_mmc_phase(_hw) container_of(_hw, struct meson_mmc_phase, hw)
static int meson_mmc_clk_get_phase(struct clk_hw *hw)
{
struct meson_mmc_phase *mmc = to_meson_mmc_phase(hw);
unsigned int phase_num = 1 << hweight_long(mmc->phase_mask);
unsigned long period_ps, p, d;
int degrees;
u32 val;
val = readl(mmc->reg);
p = (val & mmc->phase_mask) >> __ffs(mmc->phase_mask);
degrees = p * 360 / phase_num;
if (mmc->delay_mask) {
period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000,
clk_get_rate(hw->clk));
d = (val & mmc->delay_mask) >> __ffs(mmc->delay_mask);
degrees += d * mmc->delay_step_ps * 360 / period_ps;
degrees %= 360;
}
return degrees;
}
static void meson_mmc_apply_phase_delay(struct meson_mmc_phase *mmc,
unsigned int phase,
unsigned int delay)
{
u32 val;
val = readl(mmc->reg);
val &= ~mmc->phase_mask;
val |= phase << __ffs(mmc->phase_mask);
if (mmc->delay_mask) {
val &= ~mmc->delay_mask;
val |= delay << __ffs(mmc->delay_mask);
}
writel(val, mmc->reg);
}
static int meson_mmc_clk_set_phase(struct clk_hw *hw, int degrees)
{
struct meson_mmc_phase *mmc = to_meson_mmc_phase(hw);
unsigned int phase_num = 1 << hweight_long(mmc->phase_mask);
unsigned long period_ps, d = 0, r;
uint64_t p;
p = degrees % 360;
if (!mmc->delay_mask) {
p = DIV_ROUND_CLOSEST_ULL(p, 360 / phase_num);
} else {
period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000,
clk_get_rate(hw->clk));
/* First compute the phase index (p), the remainder (r) is the
* part we'll try to acheive using the delays (d).
*/
r = do_div(p, 360 / phase_num);
d = DIV_ROUND_CLOSEST(r * period_ps,
360 * mmc->delay_step_ps);
d = min(d, mmc->delay_mask >> __ffs(mmc->delay_mask));
}
meson_mmc_apply_phase_delay(mmc, p, d);
return 0;
}
static const struct clk_ops meson_mmc_clk_phase_ops = {
.get_phase = meson_mmc_clk_get_phase,
.set_phase = meson_mmc_clk_set_phase,
};
static unsigned int meson_mmc_get_timeout_msecs(struct mmc_data *data)
{
unsigned int timeout = data->timeout_ns / NSEC_PER_MSEC;
if (!timeout)
return SD_EMMC_CMD_TIMEOUT_DATA;
timeout = roundup_pow_of_two(timeout);
return min(timeout, 32768U); /* max. 2^15 ms */
}
static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
{
if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
return cmd->mrq->cmd;
else if (mmc_op_multi(cmd->opcode) &&
(!cmd->mrq->sbc || cmd->error || cmd->data->error))
return cmd->mrq->stop;
else
return NULL;
}
static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
struct mmc_request *mrq)
{
struct mmc_data *data = mrq->data;
struct scatterlist *sg;
int i;
bool use_desc_chain_mode = true;
/*
* Broken SDIO with AP6255-based WiFi on Khadas VIM Pro has been
* reported. For some strange reason this occurs in descriptor
* chain mode only. So let's fall back to bounce buffer mode
* for command SD_IO_RW_EXTENDED.
*/
if (mrq->cmd->opcode == SD_IO_RW_EXTENDED)
return;
for_each_sg(data->sg, sg, data->sg_len, i)
/* check for 8 byte alignment */
if (sg->offset & 7) {
WARN_ONCE(1, "unaligned scatterlist buffer\n");
use_desc_chain_mode = false;
break;
}
if (use_desc_chain_mode)
data->host_cookie |= SD_EMMC_DESC_CHAIN_MODE;
}
static inline bool meson_mmc_desc_chain_mode(const struct mmc_data *data)
{
return data->host_cookie & SD_EMMC_DESC_CHAIN_MODE;
}
static inline bool meson_mmc_bounce_buf_read(const struct mmc_data *data)
{
return data && data->flags & MMC_DATA_READ &&
!meson_mmc_desc_chain_mode(data);
}
static void meson_mmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct mmc_data *data = mrq->data;
if (!data)
return;
meson_mmc_get_transfer_mode(mmc, mrq);
data->host_cookie |= SD_EMMC_PRE_REQ_DONE;
if (!meson_mmc_desc_chain_mode(data))
return;
data->sg_count = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
mmc_get_dma_dir(data));
if (!data->sg_count)
dev_err(mmc_dev(mmc), "dma_map_sg failed");
}
static void meson_mmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
int err)
{
struct mmc_data *data = mrq->data;
if (data && meson_mmc_desc_chain_mode(data) && data->sg_count)
dma_unmap_sg(mmc_dev(mmc), data->sg, data->sg_len,
mmc_get_dma_dir(data));
}
static bool meson_mmc_timing_is_ddr(struct mmc_ios *ios)
{
if (ios->timing == MMC_TIMING_MMC_DDR52 ||
ios->timing == MMC_TIMING_UHS_DDR50 ||
ios->timing == MMC_TIMING_MMC_HS400)
return true;
return false;
}
/*
* Gating the clock on this controller is tricky. It seems the mmc clock
* is also used by the controller. It may crash during some operation if the
* clock is stopped. The safest thing to do, whenever possible, is to keep
* clock running at stop it at the pad using the pinmux.
*/
static void meson_mmc_clk_gate(struct meson_host *host)
{
u32 cfg;
if (host->pins_clk_gate) {
pinctrl_select_state(host->pinctrl, host->pins_clk_gate);
} else {
/*
* If the pinmux is not provided - default to the classic and
* unsafe method
*/
cfg = readl(host->regs + SD_EMMC_CFG);
cfg |= CFG_STOP_CLOCK;
writel(cfg, host->regs + SD_EMMC_CFG);
}
}
static void meson_mmc_clk_ungate(struct meson_host *host)
{
u32 cfg;
if (host->pins_clk_gate)
pinctrl_select_state(host->pinctrl, host->pins_default);
/* Make sure the clock is not stopped in the controller */
cfg = readl(host->regs + SD_EMMC_CFG);
cfg &= ~CFG_STOP_CLOCK;
writel(cfg, host->regs + SD_EMMC_CFG);
}
static int meson_mmc_clk_set(struct meson_host *host, struct mmc_ios *ios)
{
struct mmc_host *mmc = host->mmc;
unsigned long rate = ios->clock;
int ret;
u32 cfg;
/* DDR modes require higher module clock */
if (meson_mmc_timing_is_ddr(ios))
rate <<= 1;
/* Same request - bail-out */
if (host->req_rate == rate)
return 0;
/* stop clock */
meson_mmc_clk_gate(host);
host->req_rate = 0;
if (!rate) {
mmc->actual_clock = 0;
/* return with clock being stopped */
return 0;
}
/* Stop the clock during rate change to avoid glitches */
cfg = readl(host->regs + SD_EMMC_CFG);
cfg |= CFG_STOP_CLOCK;
writel(cfg, host->regs + SD_EMMC_CFG);
ret = clk_set_rate(host->mmc_clk, rate);
if (ret) {
dev_err(host->dev, "Unable to set cfg_div_clk to %lu. ret=%d\n",
rate, ret);
return ret;
}
host->req_rate = rate;
mmc->actual_clock = clk_get_rate(host->mmc_clk);
/* We should report the real output frequency of the controller */
if (meson_mmc_timing_is_ddr(ios))
mmc->actual_clock >>= 1;
dev_dbg(host->dev, "clk rate: %u Hz\n", mmc->actual_clock);
if (ios->clock != mmc->actual_clock)
dev_dbg(host->dev, "requested rate was %u\n", ios->clock);
/* (re)start clock */
meson_mmc_clk_ungate(host);
return 0;
}
/*
* The SD/eMMC IP block has an internal mux and divider used for
* generating the MMC clock. Use the clock framework to create and
* manage these clocks.
*/
static int meson_mmc_clk_init(struct meson_host *host)
{
struct clk_init_data init;
struct clk_mux *mux;
struct clk_divider *div;
struct meson_mmc_phase *core, *tx, *rx;
struct clk *clk;
char clk_name[32];
int i, ret = 0;
const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
const char *clk_parent[1];
u32 clk_reg;
/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
clk_reg = 0;
clk_reg |= CLK_ALWAYS_ON(host);
clk_reg |= CLK_DIV_MASK;
writel(clk_reg, host->regs + SD_EMMC_CLOCK);
/* get the mux parents */
for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
struct clk *clk;
char name[16];
snprintf(name, sizeof(name), "clkin%d", i);
clk = devm_clk_get(host->dev, name);
if (IS_ERR(clk)) {
if (clk != ERR_PTR(-EPROBE_DEFER))
dev_err(host->dev, "Missing clock %s\n", name);
return PTR_ERR(clk);
}
mux_parent_names[i] = __clk_get_name(clk);
}
/* create the mux */
mux = devm_kzalloc(host->dev, sizeof(*mux), GFP_KERNEL);
if (!mux)
return -ENOMEM;
snprintf(clk_name, sizeof(clk_name), "%s#mux", dev_name(host->dev));
init.name = clk_name;
init.ops = &clk_mux_ops;
init.flags = 0;
init.parent_names = mux_parent_names;
init.num_parents = MUX_CLK_NUM_PARENTS;
mux->reg = host->regs + SD_EMMC_CLOCK;
mux->shift = __ffs(CLK_SRC_MASK);
mux->mask = CLK_SRC_MASK >> mux->shift;
mux->hw.init = &init;
clk = devm_clk_register(host->dev, &mux->hw);
if (WARN_ON(IS_ERR(clk)))
return PTR_ERR(clk);
/* create the divider */
div = devm_kzalloc(host->dev, sizeof(*div), GFP_KERNEL);
if (!div)
return -ENOMEM;
snprintf(clk_name, sizeof(clk_name), "%s#div", dev_name(host->dev));
init.name = clk_name;
init.ops = &clk_divider_ops;
init.flags = CLK_SET_RATE_PARENT;
clk_parent[0] = __clk_get_name(clk);
init.parent_names = clk_parent;
init.num_parents = 1;
div->reg = host->regs + SD_EMMC_CLOCK;
div->shift = __ffs(CLK_DIV_MASK);
div->width = __builtin_popcountl(CLK_DIV_MASK);
div->hw.init = &init;
div->flags = CLK_DIVIDER_ONE_BASED;
clk = devm_clk_register(host->dev, &div->hw);
if (WARN_ON(IS_ERR(clk)))
return PTR_ERR(clk);
/* create the mmc core clock */
core = devm_kzalloc(host->dev, sizeof(*core), GFP_KERNEL);
if (!core)
return -ENOMEM;
snprintf(clk_name, sizeof(clk_name), "%s#core", dev_name(host->dev));
init.name = clk_name;
init.ops = &meson_mmc_clk_phase_ops;
init.flags = CLK_SET_RATE_PARENT;
clk_parent[0] = __clk_get_name(clk);
init.parent_names = clk_parent;
init.num_parents = 1;
core->reg = host->regs + SD_EMMC_CLOCK;
core->phase_mask = CLK_CORE_PHASE_MASK;
core->hw.init = &init;
host->mmc_clk = devm_clk_register(host->dev, &core->hw);
if (WARN_ON(PTR_ERR_OR_ZERO(host->mmc_clk)))
return PTR_ERR(host->mmc_clk);
/* create the mmc tx clock */
tx = devm_kzalloc(host->dev, sizeof(*tx), GFP_KERNEL);
if (!tx)
return -ENOMEM;
snprintf(clk_name, sizeof(clk_name), "%s#tx", dev_name(host->dev));
init.name = clk_name;
init.ops = &meson_mmc_clk_phase_ops;
init.flags = 0;
clk_parent[0] = __clk_get_name(host->mmc_clk);
init.parent_names = clk_parent;
init.num_parents = 1;
tx->reg = host->regs + SD_EMMC_CLOCK;
tx->phase_mask = CLK_TX_PHASE_MASK;
tx->delay_mask = CLK_TX_DELAY_MASK(host);
tx->delay_step_ps = CLK_DELAY_STEP_PS;
tx->hw.init = &init;
host->tx_clk = devm_clk_register(host->dev, &tx->hw);
if (WARN_ON(PTR_ERR_OR_ZERO(host->tx_clk)))
return PTR_ERR(host->tx_clk);
/* create the mmc rx clock */
rx = devm_kzalloc(host->dev, sizeof(*rx), GFP_KERNEL);
if (!rx)
return -ENOMEM;
snprintf(clk_name, sizeof(clk_name), "%s#rx", dev_name(host->dev));
init.name = clk_name;
init.ops = &meson_mmc_clk_phase_ops;
init.flags = 0;
clk_parent[0] = __clk_get_name(host->mmc_clk);
init.parent_names = clk_parent;
init.num_parents = 1;
rx->reg = host->regs + SD_EMMC_CLOCK;
rx->phase_mask = CLK_RX_PHASE_MASK;
rx->delay_mask = CLK_RX_DELAY_MASK(host);
rx->delay_step_ps = CLK_DELAY_STEP_PS;
rx->hw.init = &init;
host->rx_clk = devm_clk_register(host->dev, &rx->hw);
if (WARN_ON(PTR_ERR_OR_ZERO(host->rx_clk)))
return PTR_ERR(host->rx_clk);
/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
host->mmc->f_min = clk_round_rate(host->mmc_clk, 400000);
ret = clk_set_rate(host->mmc_clk, host->mmc->f_min);
if (ret)
return ret;
/*
* Set phases : These values are mostly the datasheet recommended ones
* except for the Tx phase. Datasheet recommends 180 but some cards
* fail at initialisation with it. 270 works just fine, it fixes these
* initialisation issues and enable eMMC DDR52 mode.
*/
clk_set_phase(host->mmc_clk, 180);
clk_set_phase(host->tx_clk, 270);
clk_set_phase(host->rx_clk, 0);
return clk_prepare_enable(host->mmc_clk);
}
static void meson_mmc_shift_map(unsigned long *map, unsigned long shift)
{
DECLARE_BITMAP(left, CLK_PHASE_POINT_NUM);
DECLARE_BITMAP(right, CLK_PHASE_POINT_NUM);
/*
* shift the bitmap right and reintroduce the dropped bits on the left
* of the bitmap
*/
bitmap_shift_right(right, map, shift, CLK_PHASE_POINT_NUM);
bitmap_shift_left(left, map, CLK_PHASE_POINT_NUM - shift,
CLK_PHASE_POINT_NUM);
bitmap_or(map, left, right, CLK_PHASE_POINT_NUM);
}
static void meson_mmc_find_next_region(unsigned long *map,
unsigned long *start,
unsigned long *stop)
{
*start = find_next_bit(map, CLK_PHASE_POINT_NUM, *start);
*stop = find_next_zero_bit(map, CLK_PHASE_POINT_NUM, *start);
}
static int meson_mmc_find_tuning_point(unsigned long *test)
{
unsigned long shift, stop, offset = 0, start = 0, size = 0;
/* Get the all good/all bad situation out the way */
if (bitmap_full(test, CLK_PHASE_POINT_NUM))
return 0; /* All points are good so point 0 will do */
else if (bitmap_empty(test, CLK_PHASE_POINT_NUM))
return -EIO; /* No successful tuning point */
/*
* Now we know there is a least one region find. Make sure it does
* not wrap by the shifting the bitmap if necessary
*/
shift = find_first_zero_bit(test, CLK_PHASE_POINT_NUM);
if (shift != 0)
meson_mmc_shift_map(test, shift);
while (start < CLK_PHASE_POINT_NUM) {
meson_mmc_find_next_region(test, &start, &stop);
if ((stop - start) > size) {
offset = start;
size = stop - start;
}
start = stop;
}
/* Get the center point of the region */
offset += (size / 2);
/* Shift the result back */
offset = (offset + shift) % CLK_PHASE_POINT_NUM;
return offset;
}
static int meson_mmc_clk_phase_tuning(struct mmc_host *mmc, u32 opcode,
struct clk *clk)
{
int point, ret;
DECLARE_BITMAP(test, CLK_PHASE_POINT_NUM);
dev_dbg(mmc_dev(mmc), "%s phase/delay tunning...\n",
__clk_get_name(clk));
bitmap_zero(test, CLK_PHASE_POINT_NUM);
/* Explore tuning points */
for (point = 0; point < CLK_PHASE_POINT_NUM; point++) {
clk_set_phase(clk, point * CLK_PHASE_STEP);
ret = mmc_send_tuning(mmc, opcode, NULL);
if (!ret)
set_bit(point, test);
}
/* Find the optimal tuning point and apply it */
point = meson_mmc_find_tuning_point(test);
if (point < 0)
return point; /* tuning failed */
clk_set_phase(clk, point * CLK_PHASE_STEP);
dev_dbg(mmc_dev(mmc), "success with phase: %d\n",
clk_get_phase(clk));
return 0;
}
static int meson_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
struct meson_host *host = mmc_priv(mmc);
return meson_mmc_clk_phase_tuning(mmc, opcode, host->rx_clk);
}
static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct meson_host *host = mmc_priv(mmc);
u32 bus_width, val;
int err;
/*
* GPIO regulator, only controls switching between 1v8 and
* 3v3, doesn't support MMC_POWER_OFF, MMC_POWER_ON.
*/
switch (ios->power_mode) {
case MMC_POWER_OFF:
if (!IS_ERR(mmc->supply.vmmc))
mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
if (!IS_ERR(mmc->supply.vqmmc) && host->vqmmc_enabled) {
regulator_disable(mmc->supply.vqmmc);
host->vqmmc_enabled = false;
}
break;
case MMC_POWER_UP:
if (!IS_ERR(mmc->supply.vmmc))
mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
/* Reset rx phase */
clk_set_phase(host->rx_clk, 0);
break;
case MMC_POWER_ON:
if (!IS_ERR(mmc->supply.vqmmc) && !host->vqmmc_enabled) {
int ret = regulator_enable(mmc->supply.vqmmc);
if (ret < 0)
dev_err(host->dev,
"failed to enable vqmmc regulator\n");
else
host->vqmmc_enabled = true;
}
break;
}
/* Bus width */
switch (ios->bus_width) {
case MMC_BUS_WIDTH_1:
bus_width = CFG_BUS_WIDTH_1;
break;
case MMC_BUS_WIDTH_4:
bus_width = CFG_BUS_WIDTH_4;
break;
case MMC_BUS_WIDTH_8:
bus_width = CFG_BUS_WIDTH_8;
break;
default:
dev_err(host->dev, "Invalid ios->bus_width: %u. Setting to 4.\n",
ios->bus_width);
bus_width = CFG_BUS_WIDTH_4;
}
val = readl(host->regs + SD_EMMC_CFG);
val &= ~CFG_BUS_WIDTH_MASK;
val |= FIELD_PREP(CFG_BUS_WIDTH_MASK, bus_width);
val &= ~CFG_DDR;
if (meson_mmc_timing_is_ddr(ios))
val |= CFG_DDR;
val &= ~CFG_CHK_DS;
if (ios->timing == MMC_TIMING_MMC_HS400)
val |= CFG_CHK_DS;
err = meson_mmc_clk_set(host, ios);
if (err)
dev_err(host->dev, "Failed to set clock: %d\n,", err);
writel(val, host->regs + SD_EMMC_CFG);
dev_dbg(host->dev, "SD_EMMC_CFG: 0x%08x\n", val);
}
static void meson_mmc_request_done(struct mmc_host *mmc,
struct mmc_request *mrq)
{
struct meson_host *host = mmc_priv(mmc);
host->cmd = NULL;
mmc_request_done(host->mmc, mrq);
}
static void meson_mmc_set_blksz(struct mmc_host *mmc, unsigned int blksz)
{
struct meson_host *host = mmc_priv(mmc);
u32 cfg, blksz_old;
cfg = readl(host->regs + SD_EMMC_CFG);
blksz_old = FIELD_GET(CFG_BLK_LEN_MASK, cfg);
if (!is_power_of_2(blksz))
dev_err(host->dev, "blksz %u is not a power of 2\n", blksz);
blksz = ilog2(blksz);
/* check if block-size matches, if not update */
if (blksz == blksz_old)
return;
dev_dbg(host->dev, "%s: update blk_len %d -> %d\n", __func__,
blksz_old, blksz);
cfg &= ~CFG_BLK_LEN_MASK;
cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, blksz);
writel(cfg, host->regs + SD_EMMC_CFG);
}
static void meson_mmc_set_response_bits(struct mmc_command *cmd, u32 *cmd_cfg)
{
if (cmd->flags & MMC_RSP_PRESENT) {
if (cmd->flags & MMC_RSP_136)
*cmd_cfg |= CMD_CFG_RESP_128;
*cmd_cfg |= CMD_CFG_RESP_NUM;
if (!(cmd->flags & MMC_RSP_CRC))
*cmd_cfg |= CMD_CFG_RESP_NOCRC;
if (cmd->flags & MMC_RSP_BUSY)
*cmd_cfg |= CMD_CFG_R1B;
} else {
*cmd_cfg |= CMD_CFG_NO_RESP;
}
}
static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg)
{
struct meson_host *host = mmc_priv(mmc);
struct sd_emmc_desc *desc = host->descs;
struct mmc_data *data = host->cmd->data;
struct scatterlist *sg;
u32 start;
int i;
if (data->flags & MMC_DATA_WRITE)
cmd_cfg |= CMD_CFG_DATA_WR;
if (data->blocks > 1) {
cmd_cfg |= CMD_CFG_BLOCK_MODE;
meson_mmc_set_blksz(mmc, data->blksz);
}
for_each_sg(data->sg, sg, data->sg_count, i) {
unsigned int len = sg_dma_len(sg);
if (data->blocks > 1)
len /= data->blksz;
desc[i].cmd_cfg = cmd_cfg;
desc[i].cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, len);
if (i > 0)
desc[i].cmd_cfg |= CMD_CFG_NO_CMD;
desc[i].cmd_arg = host->cmd->arg;
desc[i].cmd_resp = 0;
desc[i].cmd_data = sg_dma_address(sg);
}
desc[data->sg_count - 1].cmd_cfg |= CMD_CFG_END_OF_CHAIN;
dma_wmb(); /* ensure descriptor is written before kicked */
start = host->descs_dma_addr | START_DESC_BUSY;
writel(start, host->regs + SD_EMMC_START);
}
static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
{
struct meson_host *host = mmc_priv(mmc);
struct mmc_data *data = cmd->data;
u32 cmd_cfg = 0, cmd_data = 0;
unsigned int xfer_bytes = 0;
/* Setup descriptors */
dma_rmb();
host->cmd = cmd;
cmd_cfg |= FIELD_PREP(CMD_CFG_CMD_INDEX_MASK, cmd->opcode);
cmd_cfg |= CMD_CFG_OWNER; /* owned by CPU */
meson_mmc_set_response_bits(cmd, &cmd_cfg);
/* data? */
if (data) {
data->bytes_xfered = 0;
cmd_cfg |= CMD_CFG_DATA_IO;
cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
ilog2(meson_mmc_get_timeout_msecs(data)));
if (meson_mmc_desc_chain_mode(data)) {
meson_mmc_desc_chain_transfer(mmc, cmd_cfg);
return;
}
if (data->blocks > 1) {
cmd_cfg |= CMD_CFG_BLOCK_MODE;
cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK,
data->blocks);
meson_mmc_set_blksz(mmc, data->blksz);
} else {
cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, data->blksz);
}
xfer_bytes = data->blksz * data->blocks;
if (data->flags & MMC_DATA_WRITE) {
cmd_cfg |= CMD_CFG_DATA_WR;
WARN_ON(xfer_bytes > host->bounce_buf_size);
sg_copy_to_buffer(data->sg, data->sg_len,
host->bounce_buf, xfer_bytes);
dma_wmb();
}
cmd_data = host->bounce_dma_addr & CMD_DATA_MASK;
} else {
cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
ilog2(SD_EMMC_CMD_TIMEOUT));
}
/* Last descriptor */
cmd_cfg |= CMD_CFG_END_OF_CHAIN;
writel(cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
writel(cmd_data, host->regs + SD_EMMC_CMD_DAT);
writel(0, host->regs + SD_EMMC_CMD_RSP);
wmb(); /* ensure descriptor is written before kicked */
writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
}
static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct meson_host *host = mmc_priv(mmc);
bool needs_pre_post_req = mrq->data &&
!(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
if (needs_pre_post_req) {
meson_mmc_get_transfer_mode(mmc, mrq);
if (!meson_mmc_desc_chain_mode(mrq->data))
needs_pre_post_req = false;
}
if (needs_pre_post_req)
meson_mmc_pre_req(mmc, mrq);
/* Stop execution */
writel(0, host->regs + SD_EMMC_START);
meson_mmc_start_cmd(mmc, mrq->sbc ?: mrq->cmd);
if (needs_pre_post_req)
meson_mmc_post_req(mmc, mrq, 0);
}
static void meson_mmc_read_resp(struct mmc_host *mmc, struct mmc_command *cmd)
{
struct meson_host *host = mmc_priv(mmc);
if (cmd->flags & MMC_RSP_136) {
cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP3);
cmd->resp[1] = readl(host->regs + SD_EMMC_CMD_RSP2);
cmd->resp[2] = readl(host->regs + SD_EMMC_CMD_RSP1);
cmd->resp[3] = readl(host->regs + SD_EMMC_CMD_RSP);
} else if (cmd->flags & MMC_RSP_PRESENT) {
cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP);
}
}
static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
{
struct meson_host *host = dev_id;
struct mmc_command *cmd;
struct mmc_data *data;
u32 irq_en, status, raw_status;
irqreturn_t ret = IRQ_NONE;
if (WARN_ON(!host) || WARN_ON(!host->cmd))
return IRQ_NONE;
spin_lock(&host->lock);
cmd = host->cmd;
data = cmd->data;
irq_en = readl(host->regs + SD_EMMC_IRQ_EN);
raw_status = readl(host->regs + SD_EMMC_STATUS);
status = raw_status & irq_en;
cmd->error = 0;
if (status & IRQ_CRC_ERR) {
dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
cmd->error = -EILSEQ;
ret = IRQ_HANDLED;
goto out;
}
if (status & IRQ_TIMEOUTS) {
dev_dbg(host->dev, "Timeout - status 0x%08x\n", status);
cmd->error = -ETIMEDOUT;
ret = IRQ_HANDLED;
goto out;
}
meson_mmc_read_resp(host->mmc, cmd);
if (status & IRQ_SDIO) {
dev_dbg(host->dev, "IRQ: SDIO TODO.\n");
ret = IRQ_HANDLED;
}
if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
if (data && !cmd->error)
data->bytes_xfered = data->blksz * data->blocks;
if (meson_mmc_bounce_buf_read(data) ||
meson_mmc_get_next_command(cmd))
ret = IRQ_WAKE_THREAD;
else
ret = IRQ_HANDLED;
}
out:
/* ack all enabled interrupts */
writel(irq_en, host->regs + SD_EMMC_STATUS);
if (ret == IRQ_HANDLED)
meson_mmc_request_done(host->mmc, cmd->mrq);
else if (ret == IRQ_NONE)
dev_warn(host->dev,
"Unexpected IRQ! status=0x%08x, irq_en=0x%08x\n",
raw_status, irq_en);
spin_unlock(&host->lock);
return ret;
}
static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id)
{
struct meson_host *host = dev_id;
struct mmc_command *next_cmd, *cmd = host->cmd;
struct mmc_data *data;
unsigned int xfer_bytes;
if (WARN_ON(!cmd))
return IRQ_NONE;
data = cmd->data;
if (meson_mmc_bounce_buf_read(data)) {
xfer_bytes = data->blksz * data->blocks;
WARN_ON(xfer_bytes > host->bounce_buf_size);
sg_copy_from_buffer(data->sg, data->sg_len,
host->bounce_buf, xfer_bytes);
}
next_cmd = meson_mmc_get_next_command(cmd);
if (next_cmd)
meson_mmc_start_cmd(host->mmc, next_cmd);
else
meson_mmc_request_done(host->mmc, cmd->mrq);
return IRQ_HANDLED;
}
/*
* NOTE: we only need this until the GPIO/pinctrl driver can handle
* interrupts. For now, the MMC core will use this for polling.
*/
static int meson_mmc_get_cd(struct mmc_host *mmc)
{
int status = mmc_gpio_get_cd(mmc);
if (status == -ENOSYS)
return 1; /* assume present */
return status;
}
static void meson_mmc_cfg_init(struct meson_host *host)
{
u32 cfg = 0;
cfg |= FIELD_PREP(CFG_RESP_TIMEOUT_MASK,
ilog2(SD_EMMC_CFG_RESP_TIMEOUT));
cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP));
cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
writel(cfg, host->regs + SD_EMMC_CFG);
}
static int meson_mmc_card_busy(struct mmc_host *mmc)
{
struct meson_host *host = mmc_priv(mmc);
u32 regval;
regval = readl(host->regs + SD_EMMC_STATUS);
/* We are only interrested in lines 0 to 3, so mask the other ones */
return !(FIELD_GET(STATUS_DATI, regval) & 0xf);
}
static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
{
/* vqmmc regulator is available */
if (!IS_ERR(mmc->supply.vqmmc)) {
/*
* The usual amlogic setup uses a GPIO to switch from one
* regulator to the other. While the voltage ramp up is
* pretty fast, care must be taken when switching from 3.3v
* to 1.8v. Please make sure the regulator framework is aware
* of your own regulator constraints
*/
return mmc_regulator_set_vqmmc(mmc, ios);
}
/* no vqmmc regulator, assume fixed regulator at 3/3.3V */
if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
return 0;
return -EINVAL;
}
static const struct mmc_host_ops meson_mmc_ops = {
.request = meson_mmc_request,
.set_ios = meson_mmc_set_ios,
.get_cd = meson_mmc_get_cd,
.pre_req = meson_mmc_pre_req,
.post_req = meson_mmc_post_req,
.execute_tuning = meson_mmc_execute_tuning,
.card_busy = meson_mmc_card_busy,
.start_signal_voltage_switch = meson_mmc_voltage_switch,
};
static int meson_mmc_probe(struct platform_device *pdev)
{
struct resource *res;
struct meson_host *host;
struct mmc_host *mmc;
int ret, irq;
mmc = mmc_alloc_host(sizeof(struct meson_host), &pdev->dev);
if (!mmc)
return -ENOMEM;
host = mmc_priv(mmc);
host->mmc = mmc;
host->dev = &pdev->dev;
dev_set_drvdata(&pdev->dev, host);
spin_lock_init(&host->lock);
/* Get regulators and the supported OCR mask */
host->vqmmc_enabled = false;
ret = mmc_regulator_get_supply(mmc);
if (ret)
goto free_host;
ret = mmc_of_parse(mmc);
if (ret) {
if (ret != -EPROBE_DEFER)
dev_warn(&pdev->dev, "error parsing DT: %d\n", ret);
goto free_host;
}
host->data = (struct meson_mmc_data *)
of_device_get_match_data(&pdev->dev);
if (!host->data) {
ret = -EINVAL;
goto free_host;
}
ret = device_reset_optional(&pdev->dev);
if (ret) {
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev, "device reset failed: %d\n", ret);
return ret;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
host->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(host->regs)) {
ret = PTR_ERR(host->regs);
goto free_host;
}
irq = platform_get_irq(pdev, 0);
if (irq <= 0) {
dev_err(&pdev->dev, "failed to get interrupt resource.\n");
ret = -EINVAL;
goto free_host;
}
host->pinctrl = devm_pinctrl_get(&pdev->dev);
if (IS_ERR(host->pinctrl)) {
ret = PTR_ERR(host->pinctrl);
goto free_host;
}
host->pins_default = pinctrl_lookup_state(host->pinctrl,
PINCTRL_STATE_DEFAULT);
if (IS_ERR(host->pins_default)) {
ret = PTR_ERR(host->pins_default);
goto free_host;
}
host->pins_clk_gate = pinctrl_lookup_state(host->pinctrl,
"clk-gate");
if (IS_ERR(host->pins_clk_gate)) {
dev_warn(&pdev->dev,
"can't get clk-gate pinctrl, using clk_stop bit\n");
host->pins_clk_gate = NULL;
}
host->core_clk = devm_clk_get(&pdev->dev, "core");
if (IS_ERR(host->core_clk)) {
ret = PTR_ERR(host->core_clk);
goto free_host;
}
ret = clk_prepare_enable(host->core_clk);
if (ret)
goto free_host;
ret = meson_mmc_clk_init(host);
if (ret)
goto err_core_clk;
/* set config to sane default */
meson_mmc_cfg_init(host);
/* Stop execution */
writel(0, host->regs + SD_EMMC_START);
/* clear, ack and enable interrupts */
writel(0, host->regs + SD_EMMC_IRQ_EN);
writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
host->regs + SD_EMMC_STATUS);
writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
host->regs + SD_EMMC_IRQ_EN);
ret = devm_request_threaded_irq(&pdev->dev, irq, meson_mmc_irq,
meson_mmc_irq_thread, IRQF_SHARED,
NULL, host);
if (ret)
goto err_init_clk;
mmc->caps |= MMC_CAP_CMD23;
mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
mmc->max_segs = SD_EMMC_DESC_BUF_LEN / sizeof(struct sd_emmc_desc);
mmc->max_seg_size = mmc->max_req_size;
/* data bounce buffer */
host->bounce_buf_size = mmc->max_req_size;
host->bounce_buf =
dma_alloc_coherent(host->dev, host->bounce_buf_size,
&host->bounce_dma_addr, GFP_KERNEL);
if (host->bounce_buf == NULL) {
dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
ret = -ENOMEM;
goto err_init_clk;
}
host->descs = dma_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
&host->descs_dma_addr, GFP_KERNEL);
if (!host->descs) {
dev_err(host->dev, "Allocating descriptor DMA buffer failed\n");
ret = -ENOMEM;
goto err_bounce_buf;
}
mmc->ops = &meson_mmc_ops;
mmc_add_host(mmc);
return 0;
err_bounce_buf:
dma_free_coherent(host->dev, host->bounce_buf_size,
host->bounce_buf, host->bounce_dma_addr);
err_init_clk:
clk_disable_unprepare(host->mmc_clk);
err_core_clk:
clk_disable_unprepare(host->core_clk);
free_host:
mmc_free_host(mmc);
return ret;
}
static int meson_mmc_remove(struct platform_device *pdev)
{
struct meson_host *host = dev_get_drvdata(&pdev->dev);
mmc_remove_host(host->mmc);
/* disable interrupts */
writel(0, host->regs + SD_EMMC_IRQ_EN);
dma_free_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
host->descs, host->descs_dma_addr);
dma_free_coherent(host->dev, host->bounce_buf_size,
host->bounce_buf, host->bounce_dma_addr);
clk_disable_unprepare(host->mmc_clk);
clk_disable_unprepare(host->core_clk);
mmc_free_host(host->mmc);
return 0;
}
static const struct meson_mmc_data meson_gx_data = {
.tx_delay_mask = CLK_V2_TX_DELAY_MASK,
.rx_delay_mask = CLK_V2_RX_DELAY_MASK,
.always_on = CLK_V2_ALWAYS_ON,
};
static const struct meson_mmc_data meson_axg_data = {
.tx_delay_mask = CLK_V3_TX_DELAY_MASK,
.rx_delay_mask = CLK_V3_RX_DELAY_MASK,
.always_on = CLK_V3_ALWAYS_ON,
};
static const struct of_device_id meson_mmc_of_match[] = {
{ .compatible = "amlogic,meson-gx-mmc", .data = &meson_gx_data },
{ .compatible = "amlogic,meson-gxbb-mmc", .data = &meson_gx_data },
{ .compatible = "amlogic,meson-gxl-mmc", .data = &meson_gx_data },
{ .compatible = "amlogic,meson-gxm-mmc", .data = &meson_gx_data },
{ .compatible = "amlogic,meson-axg-mmc", .data = &meson_axg_data },
{}
};
MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
static struct platform_driver meson_mmc_driver = {
.probe = meson_mmc_probe,
.remove = meson_mmc_remove,
.driver = {
.name = DRIVER_NAME,
.of_match_table = of_match_ptr(meson_mmc_of_match),
},
};
module_platform_driver(meson_mmc_driver);
MODULE_DESCRIPTION("Amlogic S905*/GX*/AXG SD/eMMC driver");
MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
MODULE_LICENSE("GPL v2");
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