[PATCH 5/6] mmc: actions: add MMC driver for Actions OWL S700

Jaehoon Chung
2020-12-14T00:49:25Z

On 12/13/20 7:08 PM, Amit Singh Tomar wrote:
> From: Amit Singh Tomar <amittomer25@gmail.com>
>
> This commit adds support for MMC controllers found on Actions OWL
> S700 SoC platform.
>
> Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> ---
> drivers/mmc/Kconfig | 7 +
> drivers/mmc/Makefile | 1 +
> drivers/mmc/owl_mmc.c | 404 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 412 insertions(+)
> create mode 100644 drivers/mmc/owl_mmc.c
>
> diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
> index 14d7913..61f9c67 100644
> --- a/drivers/mmc/Kconfig
> +++ b/drivers/mmc/Kconfig
> @@ -289,6 +289,13 @@ config MMC_MXC
>
> If unsure, say N.
>
> +config MMC_OWL
> + bool "Actions OWL Multimedia Card Interface support"
> + depends on ARCH_OWL && DM_MMC && BLK
> + help
> + This selects the OWL SD/MMC host controller found on board
> + based on Actions S700 SoC.
> +
> config MMC_MXS
> bool "Freescale MXS Multimedia Card Interface support"
> depends on MX23 || MX28 || MX6 || MX7
> diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
> index 1c849cb..f270f6c 100644
> --- a/drivers/mmc/Makefile
> +++ b/drivers/mmc/Makefile
> @@ -38,6 +38,7 @@ obj-$(CONFIG_MMC_OMAP_HS) += omap_hsmmc.o
> obj-$(CONFIG_MMC_MXC) += mxcmmc.o
> obj-$(CONFIG_MMC_MXS) += mxsmmc.o
> obj-$(CONFIG_MMC_OCTEONTX) += octeontx_hsmmc.o
> +obj-$(CONFIG_MMC_OWL) += owl_mmc.o
> obj-$(CONFIG_MMC_PCI) += pci_mmc.o
> obj-$(CONFIG_PXA_MMC_GENERIC) += pxa_mmc_gen.o
> obj-$(CONFIG_$(SPL_TPL_)SUPPORT_EMMC_RPMB) += rpmb.o
> diff --git a/drivers/mmc/owl_mmc.c b/drivers/mmc/owl_mmc.c
> new file mode 100644
> index 0000000..aa0ccb7
> --- /dev/null
> +++ b/drivers/mmc/owl_mmc.c
> @@ -0,0 +1,404 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2020 Amit Singh Tomar <amittomer25@gmail.com>
> + *
> + * Driver for SD/MMC controller present on Actions Semi S700 SoC, based
> + * on Linux Driver "drivers/mmc/host/owl-mmc.c".
> + *
> + * Though, there is a bit (BSEL, BUS or DMA Special Channel Selection) that
> + * controls the data transfer from SDx_DAT register either using CPU AHB Bus
> + * or DMA channel, but seems like, it only works correctly using external DMA
> + * channel, and those special bits used in this driver is picked from vendor
> + * source exclusively for MMC/SD.
> + */
> +#include <common.h>
> +#include <clk.h>
> +#include <cpu_func.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <log.h>
> +#include <mmc.h>
> +#include <asm/io.h>
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +
> +/*
> + * SDC registers
> + */
> +#define OWL_REG_SD_EN 0x0000
> +#define OWL_REG_SD_CTL 0x0004
> +#define OWL_REG_SD_STATE 0x0008
> +#define OWL_REG_SD_CMD 0x000c
> +#define OWL_REG_SD_ARG 0x0010
> +#define OWL_REG_SD_RSPBUF0 0x0014
> +#define OWL_REG_SD_RSPBUF1 0x0018
> +#define OWL_REG_SD_RSPBUF2 0x001c
> +#define OWL_REG_SD_RSPBUF3 0x0020
> +#define OWL_REG_SD_RSPBUF4 0x0024
> +#define OWL_REG_SD_DAT 0x0028
> +#define OWL_REG_SD_BLK_SIZE 0x002c
> +#define OWL_REG_SD_BLK_NUM 0x0030
> +#define OWL_REG_SD_BUF_SIZE 0x0034
> +
> +/* SD_EN Bits */
> +#define OWL_SD_EN_RANE BIT(31)
> +#define OWL_SD_EN_RESE BIT(10)
> +#define OWL_SD_ENABLE BIT(7)
> +#define OWL_SD_EN_BSEL BIT(6)
> +#define OWL_SD_EN_DATAWID(x) (((x) & 0x3) << 0)
> +
> +/* SD_CTL Bits */
> +#define OWL_SD_CTL_TOUTEN BIT(31)
> +#define OWL_SD_CTL_DELAY_MSK GENMASK(23, 16)
> +#define OWL_SD_CTL_RDELAY(x) (((x) & 0xf) << 20)
> +#define OWL_SD_CTL_WDELAY(x) (((x) & 0xf) << 16)
> +#define OWL_SD_CTL_TS BIT(7)
> +#define OWL_SD_CTL_LBE BIT(6)
> +#define OWL_SD_CTL_TM(x) (((x) & 0xf) << 0)
> +
> +#define OWL_SD_DELAY_LOW_CLK 0x0f
> +#define OWL_SD_DELAY_MID_CLK 0x0a
> +#define OWL_SD_RDELAY_HIGH 0x08
> +#define OWL_SD_WDELAY_HIGH 0x09
> +
> +/* SD_STATE Bits */
> +#define OWL_SD_STATE_CLNR BIT(4)
> +#define OWL_SD_STATE_CRC7ER BIT(0)
> +#define OWL_SD_STATE_DAT0S BIT(7)

Order to the bit number.

> +
> +#define OWL_MMC_OCR (MMC_VDD_32_33 | MMC_VDD_33_34 | \
> + MMC_VDD_165_195)
> +
> +#define DATA_TRANSFER_TIMEOUT (3 * (100 * 1000))

Really need to set 300000?

> +
> +/*
> + * Simple DMA transfer operations defines for MMC/SD card
> + */
> +#define DMA0_CHANNEL_BASE(x) (0xe0230100 + 0x100 * (x))

What is 0xe0230100?

> +
> +#define DMA_MODE 0x0000
> +#define DMA_SOURCE 0x0004
> +#define DMA_DESTINATION 0x0008
> +#define DMA_FRAME_LEN 0x000C
> +#define DMA_FRAME_CNT 0x0010
> +#define DMA_START 0x0024
> +
> +/* DMAx_MODE */
> +#define DMA_MODE_ST(x) (((x) & 0x3) << 8)
> +#define DMA_MODE_ST_DEV DMA_MODE_ST(0)
> +#define DMA_MODE_DT(x) (((x) & 0x3) << 10)
> +#define DMA_MODE_DT_DCU DMA_MODE_DT(2)
> +#define DMA_MODE_SAM(x) (((x) & 0x3) << 16)
> +#define DMA_MODE_SAM_CONST DMA_MODE_SAM(0)
> +#define DMA_MODE_DAM(x) (((x) & 0x3) << 18)
> +#define DMA_MODE_DAM_INC DMA_MODE_DAM(1)
> +
> +
> +struct owl_mmc_plat {
> + struct mmc_config cfg;
> + struct mmc mmc;
> +};
> +
> +struct owl_mmc_priv {
> + void *reg_base;
> + struct clk clk;
> + unsigned int clock; /* Current clock */
> + unsigned int dma_drq; /* Trigger Source */
> +};
> +
> +static void owl_dma_config(void *dma_base, unsigned int drq,
> + unsigned int src, unsigned int dst,
> + unsigned int len)
> +{
> + unsigned int mode = drq;
> + u8 frame_cnt = 0x1;

Does it need to use frame_cnt variable?

> +
> + /* Set Source and Destination adderess mode */
> + mode |= (DMA_MODE_ST_DEV | DMA_MODE_SAM_CONST | DMA_MODE_DT_DCU |
> + DMA_MODE_DAM_INC);
> +
> + writel(mode, dma_base + DMA_MODE);
> + writel(src, dma_base + DMA_SOURCE);
> + writel(dst, dma_base + DMA_DESTINATION);
> + writel(len, dma_base + DMA_FRAME_LEN);
> + writel(frame_cnt, dma_base + DMA_FRAME_CNT);
> +}
> +
> +static void owl_mmc_prepare_data(struct owl_mmc_priv *priv,
> + struct mmc_data *data)
> +{
> + unsigned int reg, total;
> + uint32_t buf = 0;
> +
> + reg = readl(priv->reg_base + OWL_REG_SD_EN);
> + reg |= OWL_SD_EN_BSEL;
> + writel(reg, priv->reg_base + OWL_REG_SD_EN);
> +
> + writel(data->blocks, priv->reg_base + OWL_REG_SD_BLK_NUM);
> + writel(data->blocksize, priv->reg_base + OWL_REG_SD_BLK_SIZE);
> + total = data->blocksize * data->blocks;
> +
> + if (data->blocksize < 512)
> + writel(total, priv->reg_base + OWL_REG_SD_BUF_SIZE);
> + else
> + writel(512, priv->reg_base + OWL_REG_SD_BUF_SIZE);

Is it right to set to 512?

> +
> + /* DMA STOP */
> + writel(0x0, (DMA0_CHANNEL_BASE(2) + DMA_START));
> +
> + if (data) {
> + if (data->flags == MMC_DATA_READ) {
> + buf = (ulong) (data->dest);
> + owl_dma_config((void *) DMA0_CHANNEL_BASE(2),
> + priv->dma_drq,
> + (ulong) priv->reg_base +
> + OWL_REG_SD_DAT,
> + buf, total);
> + invalidate_dcache_range(buf, buf + total);
> + } else if (data->flags == MMC_DATA_WRITE) {

Not need to use "else if", because it shoud be MMC_DATA_WRITE.

> + buf = (ulong) (data->src);
> + owl_dma_config((void *) DMA0_CHANNEL_BASE(2),
> + priv->dma_drq,
> + buf,
> + (ulong) priv->reg_base +
> + OWL_REG_SD_DAT,
> + total);
> + flush_dcache_range(buf, buf + total);
> + }
> + /* DMA START */
> + writel(0x1, (DMA0_CHANNEL_BASE(2) + DMA_START));
> + }
> +}
> +
> +static int owl_mmc_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
> + struct mmc_data *data)
> +{
> + struct owl_mmc_priv *priv = dev_get_priv(dev);
> + unsigned int cmd_rsp_mask, mode, reg;
> + int timeout = DATA_TRANSFER_TIMEOUT;
> +
> + reg = readl(priv->reg_base + OWL_REG_SD_EN);
> + reg |= OWL_SD_ENABLE;
> + writel(reg, priv->reg_base + OWL_REG_SD_EN);
> +
> + /* setup response */
> + switch (cmd->resp_type) {
> + case MMC_RSP_NONE:
> + break;
> + case MMC_RSP_R1:
> + if (data) {
> + if (data->flags == MMC_DATA_READ)
> + mode = OWL_SD_CTL_TM(4);
> + else
> + mode = OWL_SD_CTL_TM(5);
> + } else {
> + mode = OWL_SD_CTL_TM(1);
> + }
> + cmd_rsp_mask = OWL_SD_STATE_CLNR | OWL_SD_STATE_CRC7ER;
> + break;
> + case MMC_RSP_R1b:
> + mode = OWL_SD_CTL_TM(3);
> + cmd_rsp_mask = OWL_SD_STATE_CLNR | OWL_SD_STATE_CRC7ER;
> + break;
> + case MMC_RSP_R2:
> + mode = OWL_SD_CTL_TM(2);
> + cmd_rsp_mask = OWL_SD_STATE_CLNR | OWL_SD_STATE_CRC7ER;
> + break;
> + case MMC_RSP_R3:
> + cmd->cmdarg = 0x40ff8000;

I don't know why set to cmdarg at here?

> + mode = OWL_SD_CTL_TM(1);
> + cmd_rsp_mask = OWL_SD_STATE_CLNR;
> + break;
> + default:
> + printf("error: no math command RSP flag %x\n", cmd->cmdarg);
> + return -1;

Not use -1, instead use error number.

> + }
> +
> + mode |= (readl(priv->reg_base + OWL_REG_SD_CTL) & (0xff << 16));
> +
> + /* setup command */
> + writel(cmd->cmdidx, priv->reg_base + OWL_REG_SD_CMD);
> + writel(cmd->cmdarg, priv->reg_base + OWL_REG_SD_ARG);
> +
> + /* Set LBE to send clk at the end of last read block */
> + if (data)
> + mode |= (OWL_SD_CTL_TS | OWL_SD_CTL_LBE | 0xE4000000);
> + else
> + mode |= OWL_SD_CTL_TS;
> +
> + if (data)
> + owl_mmc_prepare_data(priv, data);
> +
> + /* Start transfer */
> + writel(mode, priv->reg_base + OWL_REG_SD_CTL);
> +
> + while ((readl(priv->reg_base + OWL_REG_SD_CTL) & OWL_SD_CTL_TS)
> + && timeout--)
> + udelay(20);

Use readl_poll_timeout()?

> +
> + if (!timeout) {
> + printf("error: transferred data timeout\n");
> + return -ETIMEDOUT;
> + }
> +
> + if (cmd->resp_type & MMC_RSP_136) {
> + cmd->response[3] = readl(priv->reg_base + OWL_REG_SD_RSPBUF0);
> + cmd->response[2] = readl(priv->reg_base + OWL_REG_SD_RSPBUF1);
> + cmd->response[1] = readl(priv->reg_base + OWL_REG_SD_RSPBUF2);
> + cmd->response[0] = readl(priv->reg_base + OWL_REG_SD_RSPBUF3);
> + } else {
> + u32 rsp[2];
> +
> + rsp[0] = readl(priv->reg_base + OWL_REG_SD_RSPBUF0);
> + rsp[1] = readl(priv->reg_base + OWL_REG_SD_RSPBUF1);
> + cmd->response[0] = rsp[1] << 24 | rsp[0] >> 8;
> + cmd->response[1] = rsp[1] >> 8;
> + }
> +
> + if (data) {
> + /* DMA STOP */
> + writel(0x0, (DMA0_CHANNEL_BASE(2) + DMA_START));
> + /* Transmission STOP */
> + while (readl(priv->reg_base + OWL_REG_SD_CTL) & OWL_SD_CTL_TS)
> + clrbits_le32(priv->reg_base + OWL_REG_SD_CTL,
> + OWL_SD_CTL_TS);
> + }
> +
> + return 0;
> +}
> +
> +static void owl_mmc_clk_set(struct owl_mmc_priv *priv, int rate)
> +{
> + u32 reg;
> +
> + reg = readl(priv->reg_base + OWL_REG_SD_CTL);
> + reg &= ~OWL_SD_CTL_DELAY_MSK;
> +
> + /* Set RDELAY and WDELAY based on the clock */
> + if (rate <= 1000000) {
> + writel(reg | OWL_SD_CTL_RDELAY(OWL_SD_DELAY_LOW_CLK) |
> + OWL_SD_CTL_WDELAY(OWL_SD_DELAY_LOW_CLK),
> + priv->reg_base + OWL_REG_SD_CTL);
> + } else if ((rate > 1000000) && (rate <= 26000000)) {
> + writel(reg | OWL_SD_CTL_RDELAY(OWL_SD_DELAY_MID_CLK) |
> + OWL_SD_CTL_WDELAY(OWL_SD_DELAY_MID_CLK),
> + priv->reg_base + OWL_REG_SD_CTL);
> + } else if ((rate > 26000000) && (rate <= 52000000)) {
> + writel(reg | OWL_SD_CTL_RDELAY(OWL_SD_RDELAY_HIGH) |
> + OWL_SD_CTL_WDELAY(OWL_SD_WDELAY_HIGH),
> + priv->reg_base + OWL_REG_SD_CTL);
> + } else {
> + printf("SD clock rate not supported\n");
> + }

I think that you can make more readable than now.

if (rate <= 1000000) {
delay = OWL_SD_DELAY_LOW_CLK;
} else if ( ...) {
delay = OWL_SD_DELAY_MID_CLK;
} else if (....) {
delay = OWL_SD_DELAY_HIGH_CLK;
}

writel(reg | OWL_SD_CTRL_RDELAY(delay) | OWL_SD_CTL_WDELAY(delay)...);

> +}
> +
> +static int owl_mmc_set_ios(struct udevice *dev)
> +{
> + struct owl_mmc_priv *priv = dev_get_priv(dev);
> + struct owl_mmc_plat *plat = dev_get_platdata(dev);
> + struct mmc *mmc = &plat->mmc;
> + u32 reg, ret;
> +
> + if (mmc->clock != priv->clock) {
> + priv->clock = mmc->clock;
> + owl_mmc_clk_set(priv, mmc->clock);
> + }
> +
> + ret = clk_set_rate(&priv->clk, mmc->clock);
> + if (IS_ERR_VALUE(ret))
> + return ret;
> +
> + ret = clk_enable(&priv->clk);
> + if (ret)
> + return ret;
> +
> + /* Set the Bus width */
> + reg = readl(priv->reg_base + OWL_REG_SD_EN);
> + reg &= ~0x03;

Use macro, not 0x03.

> + if (mmc->bus_width == 8)
> + reg |= OWL_SD_EN_DATAWID(2);
> + else if (mmc->bus_width == 4)
> + reg |= OWL_SD_EN_DATAWID(1);
> +
> + writel(reg, priv->reg_base + OWL_REG_SD_EN);
> +
> + return 0;
> +}
> +
> +static const struct dm_mmc_ops owl_mmc_ops = {
> + .send_cmd = owl_mmc_send_cmd,
> + .set_ios = owl_mmc_set_ios,
> +};
> +
> +static int owl_mmc_probe(struct udevice *dev)
> +{
> + struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
> + struct owl_mmc_plat *plat = dev_get_platdata(dev);
> + struct owl_mmc_priv *priv = dev_get_priv(dev);
> + struct mmc_config *cfg = &plat->cfg;
> + int bus_width, ret;
> + fdt_addr_t addr;
> +
> + cfg->name = dev->name;
> + cfg->voltages = OWL_MMC_OCR;
> + cfg->f_min = 400000;
> + cfg->f_max = 52000000;
> + cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
> +
> + bus_width = dev_read_u32_default(dev, "bus-width", 1);

Use mmc_of_parse(). It's generic parser.

Best Regards,
Jaehoon Chung

> + switch (bus_width) {
> + case 8:
> + cfg->host_caps |= MMC_MODE_8BIT;
> + /* Hosts capable of 8-bit transfers can also do 4 bits */
> + case 4:
> + cfg->host_caps |= MMC_MODE_4BIT;
> + break;
> + case 1:
> + break;
> + default:
> + printf("Invalid bus-width value %u\n", bus_width);
> + }
> + cfg->host_caps |= MMC_MODE_HS | MMC_MODE_HS_52MHz;
> +
> + addr = dev_read_addr(dev);
> + if (addr == FDT_ADDR_T_NONE)
> + return -EINVAL;
> +
> + priv->reg_base = (void *)addr;
> + priv->dma_drq = 0x2;
> +
> + ret = clk_get_by_index(dev, 0, &priv->clk);
> + if (ret) {
> + debug("clk_get_by_index() failed: %d\n", ret);
> + return ret;
> + }
> +
> + upriv->mmc = &plat->mmc;
> +
> + return 0;
> +}
> +
> +static int owl_mmc_bind(struct udevice *dev)
> +{
> + struct owl_mmc_plat *plat = dev_get_platdata(dev);
> +
> + return mmc_bind(dev, &plat->mmc, &plat->cfg);
> +}
> +
> +static const struct udevice_id owl_mmc_ids[] = {
> + { .compatible = "actions,s700-mmc" },
> + { .compatible = "actions,owl-mmc" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(owl_mmc_drv) = {
> + .name = "owl_mmc",
> + .id = UCLASS_MMC,
> + .of_match = owl_mmc_ids,
> + .bind = owl_mmc_bind,
> + .probe = owl_mmc_probe,
> + .ops = &owl_mmc_ops,
> + .platdata_auto_alloc_size = sizeof(struct owl_mmc_plat),
> + .priv_auto_alloc_size = sizeof(struct owl_mmc_priv),
> +};
>