[PATCH v10 03/15] ARM: sunxi: Add driver for SD/MMC hosts found on Allwinner sunxi SoCs

Ulf Hansson
2014-05-05T12:41:35Z

On 2 May 2014 17:57, Hans de Goede <hdegoede@redhat.com> wrote:
> From: David Lanzend?rfer <david.lanzendoerfer@o2s.ch>
>
> The Allwinner sunxi mmc host uses dma in bus-master mode using a built-in
> designware idmac controller, which is identical to the one found in the mmc-dw
> hosts. However the rest of the host is not identical to mmc-dw, it deals with
> sending stop commands in hardware which makes it significantly different
> from the mmc-dw devices.
>
> HdG: Various cleanups and fixes.
>
> Signed-off-by: David Lanzend?rfer <david.lanzendoerfer@o2s.ch>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> .../devicetree/bindings/mmc/sunxi-mmc.txt | 43 +
> drivers/mmc/host/Kconfig | 7 +
> drivers/mmc/host/Makefile | 2 +
> drivers/mmc/host/sunxi-mmc.c | 1125 ++++++++++++++++++++
> 4 files changed, 1177 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mmc/sunxi-mmc.txt
> create mode 100644 drivers/mmc/host/sunxi-mmc.c
>
> diff --git a/Documentation/devicetree/bindings/mmc/sunxi-mmc.txt b/Documentation/devicetree/bindings/mmc/sunxi-mmc.txt
> new file mode 100644
> index 0000000..91b3a34
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/sunxi-mmc.txt
> @@ -0,0 +1,43 @@
> +* Allwinner sunxi MMC controller
> +
> +The highspeed MMC host controller on Allwinner SoCs provides an interface
> +for MMC, SD and SDIO types of memory cards.
> +
> +Supported maximum speeds are the ones of the eMMC standard 4.5 as well
> +as the speed of SD standard 3.0.
> +Absolute maximum transfer rate is 200MB/s
> +
> +Required properties:
> + - compatible : "allwinner,sun4i-a10-mmc" or "allwinner,sun5i-a13-mmc"
> + - reg : mmc controller base registers
> + - clocks : a list with 2 phandle + clock specifier pairs
> + - clock-names : must contain "ahb" and "mmc"
> + - interrupts : mmc controller interrupt
> +
> +Optional properties:
> + - resets : phandle + reset specifier pair
> + - reset-names : must contain "ahb"
> + - for cd, bus-width and additional generic mmc parameters
> + please refer to mmc.txt within this directory
> +
> +Examples:
> + - Within .dtsi:
> + mmc0: mmc at 01c0f000 {
> + compatible = "allwinner,sun5i-a13-mmc";
> + reg = <0x01c0f000 0x1000>;
> + clocks = <&ahb_gates 8>, <&mmc0_clk>;
> + clock-names = "ahb", "mod";
> + interrupts = <0 32 4>;
> + status = "disabled";
> + };
> +
> + - Within dts:
> + mmc0: mmc at 01c0f000 {
> + pinctrl-names = "default", "default";
> + pinctrl-0 = <&mmc0_pins_a>;
> + pinctrl-1 = <&mmc0_cd_pin_reference_design>;
> + bus-width = <4>;
> + cd-gpios = <&pio 7 1 0>; /* PH1 */
> + cd-inverted;
> + status = "okay";
> + };
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 8aaf8c1..d50ac1c 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -694,3 +694,10 @@ config MMC_REALTEK_PCI
> help
> Say Y here to include driver code to support SD/MMC card interface
> of Realtek PCI-E card reader
> +
> +config MMC_SUNXI
> + tristate "Allwinner sunxi SD/MMC Host Controller support"
> + depends on ARCH_SUNXI
> + help
> + This selects support for the SD/MMC Host Controller on
> + Allwinner sunxi SoCs.
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index 0c8aa5e..c706c0f 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -53,6 +53,8 @@ obj-$(CONFIG_MMC_WMT) += wmt-sdmmc.o
>
> obj-$(CONFIG_MMC_REALTEK_PCI) += rtsx_pci_sdmmc.o
>
> +obj-$(CONFIG_MMC_SUNXI) += sunxi-mmc.o
> +
> obj-$(CONFIG_MMC_SDHCI_PLTFM) += sdhci-pltfm.o
> obj-$(CONFIG_MMC_SDHCI_CNS3XXX) += sdhci-cns3xxx.o
> obj-$(CONFIG_MMC_SDHCI_ESDHC_IMX) += sdhci-esdhc-imx.o
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> new file mode 100644
> index 0000000..2706b64
> --- /dev/null
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -0,0 +1,1125 @@
> +/*
> + * Driver for sunxi SD/MMC host controllers
> + * (C) Copyright 2007-2011 Reuuimlla Technology Co., Ltd.
> + * (C) Copyright 2007-2011 Aaron Maoye <leafy.myeh@reuuimllatech.com>
> + * (C) Copyright 2013-2014 O2S GmbH <www.o2s.ch>
> + * (C) Copyright 2013-2014 David Lanzend?rfer <david.lanzendoerfer@o2s.ch>
> + * (C) Copyright 2013-2014 Hans de Goede <hdegoede@redhat.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/io.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +
> +#include <linux/clk.h>
> +#include <linux/clk-private.h>
> +#include <linux/clk/sunxi.h>
> +
> +#include <linux/gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/spinlock.h>
> +#include <linux/scatterlist.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/slab.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/reset.h>
> +
> +#include <linux/of_address.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_platform.h>
> +
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/sd.h>
> +#include <linux/mmc/sdio.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/mmc/core.h>
> +#include <linux/mmc/card.h>
> +#include <linux/mmc/slot-gpio.h>
> +
> +/* register offset definitions */
> +#define SDXC_REG_GCTRL (0x00) /* SMC Global Control Register */
> +#define SDXC_REG_CLKCR (0x04) /* SMC Clock Control Register */
> +#define SDXC_REG_TMOUT (0x08) /* SMC Time Out Register */
> +#define SDXC_REG_WIDTH (0x0C) /* SMC Bus Width Register */
> +#define SDXC_REG_BLKSZ (0x10) /* SMC Block Size Register */
> +#define SDXC_REG_BCNTR (0x14) /* SMC Byte Count Register */
> +#define SDXC_REG_CMDR (0x18) /* SMC Command Register */
> +#define SDXC_REG_CARG (0x1C) /* SMC Argument Register */
> +#define SDXC_REG_RESP0 (0x20) /* SMC Response Register 0 */
> +#define SDXC_REG_RESP1 (0x24) /* SMC Response Register 1 */
> +#define SDXC_REG_RESP2 (0x28) /* SMC Response Register 2 */
> +#define SDXC_REG_RESP3 (0x2C) /* SMC Response Register 3 */
> +#define SDXC_REG_IMASK (0x30) /* SMC Interrupt Mask Register */
> +#define SDXC_REG_MISTA (0x34) /* SMC Masked Interrupt Status Register */
> +#define SDXC_REG_RINTR (0x38) /* SMC Raw Interrupt Status Register */
> +#define SDXC_REG_STAS (0x3C) /* SMC Status Register */
> +#define SDXC_REG_FTRGL (0x40) /* SMC FIFO Threshold Watermark Registe */
> +#define SDXC_REG_FUNS (0x44) /* SMC Function Select Register */
> +#define SDXC_REG_CBCR (0x48) /* SMC CIU Byte Count Register */
> +#define SDXC_REG_BBCR (0x4C) /* SMC BIU Byte Count Register */
> +#define SDXC_REG_DBGC (0x50) /* SMC Debug Enable Register */
> +#define SDXC_REG_HWRST (0x78) /* SMC Card Hardware Reset for Register */
> +#define SDXC_REG_DMAC (0x80) /* SMC IDMAC Control Register */
> +#define SDXC_REG_DLBA (0x84) /* SMC IDMAC Descriptor List Base Addre */
> +#define SDXC_REG_IDST (0x88) /* SMC IDMAC Status Register */
> +#define SDXC_REG_IDIE (0x8C) /* SMC IDMAC Interrupt Enable Register */
> +#define SDXC_REG_CHDA (0x90)
> +#define SDXC_REG_CBDA (0x94)
> +
> +#define mci_readl(host, reg) \
> + readl((host)->reg_base + SDXC_##reg)
> +#define mci_writel(host, reg, value) \
> + writel((value), (host)->reg_base + SDXC_##reg)

mci_readl|writel - why those function names? Wouldn't it make more
sense if those relates to this driver's name instead somehow?

> +
> +/* global control register bits */
> +#define SDXC_SOFT_RESET BIT(0)
> +#define SDXC_FIFO_RESET BIT(1)
> +#define SDXC_DMA_RESET BIT(2)
> +#define SDXC_INTERRUPT_ENABLE_BIT BIT(4)
> +#define SDXC_DMA_ENABLE_BIT BIT(5)
> +#define SDXC_DEBOUNCE_ENABLE_BIT BIT(8)
> +#define SDXC_POSEDGE_LATCH_DATA BIT(9)
> +#define SDXC_DDR_MODE BIT(10)
> +#define SDXC_MEMORY_ACCESS_DONE BIT(29)
> +#define SDXC_ACCESS_DONE_DIRECT BIT(30)
> +#define SDXC_ACCESS_BY_AHB BIT(31)
> +#define SDXC_ACCESS_BY_DMA (0 << 31)
> +#define SDXC_HARDWARE_RESET \
> + (SDXC_SOFT_RESET | SDXC_FIFO_RESET | SDXC_DMA_RESET)
> +
> +/* clock control bits */
> +#define SDXC_CARD_CLOCK_ON BIT(16)
> +#define SDXC_LOW_POWER_ON BIT(17)
> +
> +/* bus width */
> +#define SDXC_WIDTH1 0
> +#define SDXC_WIDTH4 1
> +#define SDXC_WIDTH8 2
> +
> +/* smc command bits */
> +#define SDXC_RESP_EXPIRE BIT(6)
> +#define SDXC_LONG_RESPONSE BIT(7)
> +#define SDXC_CHECK_RESPONSE_CRC BIT(8)
> +#define SDXC_DATA_EXPIRE BIT(9)
> +#define SDXC_WRITE BIT(10)
> +#define SDXC_SEQUENCE_MODE BIT(11)
> +#define SDXC_SEND_AUTO_STOP BIT(12)
> +#define SDXC_WAIT_PRE_OVER BIT(13)
> +#define SDXC_STOP_ABORT_CMD BIT(14)
> +#define SDXC_SEND_INIT_SEQUENCE BIT(15)
> +#define SDXC_UPCLK_ONLY BIT(21)
> +#define SDXC_READ_CEATA_DEV BIT(22)
> +#define SDXC_CCS_EXPIRE BIT(23)
> +#define SDXC_ENABLE_BIT_BOOT BIT(24)
> +#define SDXC_ALT_BOOT_OPTIONS BIT(25)
> +#define SDXC_BOOT_ACK_EXPIRE BIT(26)
> +#define SDXC_BOOT_ABORT BIT(27)
> +#define SDXC_VOLTAGE_SWITCH BIT(28)
> +#define SDXC_USE_HOLD_REGISTER BIT(29)
> +#define SDXC_START BIT(31)
> +
> +/* interrupt bits */
> +#define SDXC_RESP_ERROR BIT(1)
> +#define SDXC_COMMAND_DONE BIT(2)
> +#define SDXC_DATA_OVER BIT(3)
> +#define SDXC_TX_DATA_REQUEST BIT(4)
> +#define SDXC_RX_DATA_REQUEST BIT(5)
> +#define SDXC_RESP_CRC_ERROR BIT(6)
> +#define SDXC_DATA_CRC_ERROR BIT(7)
> +#define SDXC_RESP_TIMEOUT BIT(8)
> +#define SDXC_DATA_TIMEOUT BIT(9)
> +#define SDXC_VOLTAGE_CHANGE_DONE BIT(10)
> +#define SDXC_FIFO_RUN_ERROR BIT(11)
> +#define SDXC_HARD_WARE_LOCKED BIT(12)
> +#define SDXC_START_BIT_ERROR BIT(13)
> +#define SDXC_AUTO_COMMAND_DONE BIT(14)
> +#define SDXC_END_BIT_ERROR BIT(15)
> +#define SDXC_SDIO_INTERRUPT BIT(16)
> +#define SDXC_CARD_INSERT BIT(30)
> +#define SDXC_CARD_REMOVE BIT(31)
> +#define SDXC_INTERRUPT_ERROR_BIT \
> + (SDXC_RESP_ERROR | SDXC_RESP_CRC_ERROR | SDXC_DATA_CRC_ERROR | \
> + SDXC_RESP_TIMEOUT | SDXC_DATA_TIMEOUT | SDXC_FIFO_RUN_ERROR | \
> + SDXC_HARD_WARE_LOCKED | SDXC_START_BIT_ERROR | SDXC_END_BIT_ERROR)
> +#define SDXC_INTERRUPT_DONE_BIT \
> + (SDXC_AUTO_COMMAND_DONE | SDXC_DATA_OVER | \
> + SDXC_COMMAND_DONE | SDXC_VOLTAGE_CHANGE_DONE)
> +
> +/* status */
> +#define SDXC_RXWL_FLAG BIT(0)
> +#define SDXC_TXWL_FLAG BIT(1)
> +#define SDXC_FIFO_EMPTY BIT(2)
> +#define SDXC_FIFO_FULL BIT(3)
> +#define SDXC_CARD_PRESENT BIT(8)
> +#define SDXC_CARD_DATA_BUSY BIT(9)
> +#define SDXC_DATA_FSM_BUSY BIT(10)
> +#define SDXC_DMA_REQUEST BIT(31)
> +#define SDXC_FIFO_SIZE 16
> +
> +/* Function select */
> +#define SDXC_CEATA_ON (0xceaa << 16)
> +#define SDXC_SEND_IRQ_RESPONSE BIT(0)
> +#define SDXC_SDIO_READ_WAIT BIT(1)
> +#define SDXC_ABORT_READ_DATA BIT(2)
> +#define SDXC_SEND_CCSD BIT(8)
> +#define SDXC_SEND_AUTO_STOPCCSD BIT(9)
> +#define SDXC_CEATA_DEV_IRQ_ENABLE BIT(10)
> +
> +/* IDMA controller bus mod bit field */
> +#define SDXC_IDMAC_SOFT_RESET BIT(0)
> +#define SDXC_IDMAC_FIX_BURST BIT(1)
> +#define SDXC_IDMAC_IDMA_ON BIT(7)
> +#define SDXC_IDMAC_REFETCH_DES BIT(31)
> +
> +/* IDMA status bit field */
> +#define SDXC_IDMAC_TRANSMIT_INTERRUPT BIT(0)
> +#define SDXC_IDMAC_RECEIVE_INTERRUPT BIT(1)
> +#define SDXC_IDMAC_FATAL_BUS_ERROR BIT(2)
> +#define SDXC_IDMAC_DESTINATION_INVALID BIT(4)
> +#define SDXC_IDMAC_CARD_ERROR_SUM BIT(5)
> +#define SDXC_IDMAC_NORMAL_INTERRUPT_SUM BIT(8)
> +#define SDXC_IDMAC_ABNORMAL_INTERRUPT_SUM BIT(9)
> +#define SDXC_IDMAC_HOST_ABORT_INTERRUPT BIT(10)
> +#define SDXC_IDMAC_IDLE (0 << 13)
> +#define SDXC_IDMAC_SUSPEND (1 << 13)
> +#define SDXC_IDMAC_DESC_READ (2 << 13)
> +#define SDXC_IDMAC_DESC_CHECK (3 << 13)
> +#define SDXC_IDMAC_READ_REQUEST_WAIT (4 << 13)
> +#define SDXC_IDMAC_WRITE_REQUEST_WAIT (5 << 13)
> +#define SDXC_IDMAC_READ (6 << 13)
> +#define SDXC_IDMAC_WRITE (7 << 13)
> +#define SDXC_IDMAC_DESC_CLOSE (8 << 13)
> +
> +/*
> +* If the idma-des-size-bits of property is ie 13, bufsize bits are:
> +* Bits 0-12: buf1 size
> +* Bits 13-25: buf2 size
> +* Bits 26-31: not used
> +* Since we only ever set buf1 size, we can simply store it directly.
> +*/
> +#define SDXC_IDMAC_DES0_DIC BIT(1) /* disable interrupt on completion */
> +#define SDXC_IDMAC_DES0_LD BIT(2) /* last descriptor */
> +#define SDXC_IDMAC_DES0_FD BIT(3) /* first descriptor */
> +#define SDXC_IDMAC_DES0_CH BIT(4) /* chain mode */
> +#define SDXC_IDMAC_DES0_ER BIT(5) /* end of ring */
> +#define SDXC_IDMAC_DES0_CES BIT(30) /* card error summary */
> +#define SDXC_IDMAC_DES0_OWN BIT(31) /* 1-idma owns it, 0-host owns it */
> +
> +struct sunxi_idma_des {
> + u32 config;
> + u32 buf_size;
> + u32 buf_addr_ptr1;
> + u32 buf_addr_ptr2;
> +};
> +
> +struct sunxi_mmc_host {
> + struct mmc_host *mmc;
> + struct regulator *vmmc;

Instead of having a specific regulator for this driver, please use the
mmc_regulator_get_supply API.

> + struct reset_control *reset;
> +
> + /* IO mapping base */
> + void __iomem *reg_base;
> +
> + spinlock_t lock;
> + struct tasklet_struct manual_stop_tasklet;

Any reason why you can't use a threaded IRQ handler instead of a tasklet?

> +
> + /* clock management */
> + struct clk *clk_ahb;
> + struct clk *clk_mod;
> +
> + /* ios information */
> + u32 clk_mod_rate;
> + u32 bus_width;
> + u32 idma_des_size_bits;
> + u32 ddr;
> + u32 voltage_switching;

Are these ios informations actually needed. Can't at lease some of
them be fetched from the mmc_host struct instead?

> +
> + /* irq */
> + int irq;
> + u32 int_sum;
> + u32 sdio_imask;
> +
> + /* flags */
> + bool wait_dma;
> +
> + dma_addr_t sg_dma;
> + void *sg_cpu;
> +
> + struct mmc_request *mrq;
> + struct mmc_request *manual_stop_mrq;
> + u32 ferror;
> +};
> +
> +static int sunxi_mmc_init_host(struct mmc_host *mmc)
> +{
> + u32 rval;
> + struct sunxi_mmc_host *smc_host = mmc_priv(mmc);
> + int ret;
> +
> + ret = clk_prepare_enable(smc_host->clk_ahb);
> + if (ret) {
> + dev_err(mmc_dev(smc_host->mmc), "AHB clk err %d\n", ret);
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(smc_host->clk_mod);
> + if (ret) {
> + dev_err(mmc_dev(smc_host->mmc), "MOD clk err %d\n", ret);
> + clk_disable_unprepare(smc_host->clk_ahb);
> + return ret;
> + }
> +
> + if (smc_host->reset) {
> + ret = reset_control_deassert(smc_host->reset);
> + if (ret) {
> + dev_err(mmc_dev(smc_host->mmc), "reset err %d\n", ret);
> + clk_disable_unprepare(smc_host->clk_ahb);
> + clk_disable_unprepare(smc_host->clk_mod);
> + return ret;
> + }
> + }
> +
> + /* reset controller */
> + rval = mci_readl(smc_host, REG_GCTRL);
> + rval |= SDXC_HARDWARE_RESET;
> + mci_writel(smc_host, REG_GCTRL, rval);
> +
> + mci_writel(smc_host, REG_FTRGL, 0x20070008);
> + mci_writel(smc_host, REG_TMOUT, 0xffffffff);
> + mci_writel(smc_host, REG_IMASK, smc_host->sdio_imask);
> + mci_writel(smc_host, REG_RINTR, 0xffffffff);
> + mci_writel(smc_host, REG_DBGC, 0xdeb);
> + mci_writel(smc_host, REG_FUNS, SDXC_CEATA_ON);
> + mci_writel(smc_host, REG_DLBA, smc_host->sg_dma);
> +
> + rval = mci_readl(smc_host, REG_GCTRL);
> + rval |= SDXC_INTERRUPT_ENABLE_BIT;
> + rval &= ~SDXC_ACCESS_DONE_DIRECT;
> + mci_writel(smc_host, REG_GCTRL, rval);
> +
> + return 0;
> +}
> +
> +static void sunxi_mmc_exit_host(struct sunxi_mmc_host *smc_host)
> +{
> + mci_writel(smc_host, REG_GCTRL, SDXC_HARDWARE_RESET);
> +
> + if (smc_host->reset)
> + reset_control_assert(smc_host->reset);
> +
> + clk_disable_unprepare(smc_host->clk_ahb);
> + clk_disable_unprepare(smc_host->clk_mod);
> +}
> +
> +/* /\* UHS-I Operation Modes */
> +/* * DS 25MHz 12.5MB/s 3.3V */
> +/* * HS 50MHz 25MB/s 3.3V */
> +/* * SDR12 25MHz 12.5MB/s 1.8V */
> +/* * SDR25 50MHz 25MB/s 1.8V */
> +/* * SDR50 100MHz 50MB/s 1.8V */
> +/* * SDR104 208MHz 104MB/s 1.8V */
> +/* * DDR50 50MHz 50MB/s 1.8V */
> +/* * MMC Operation Modes */
> +/* * DS 26MHz 26MB/s 3/1.8/1.2V */
> +/* * HS 52MHz 52MB/s 3/1.8/1.2V */
> +/* * HSDDR 52MHz 104MB/s 3/1.8/1.2V */
> +/* * HS200 200MHz 200MB/s 1.8/1.2V */
> +/* * */
> +/* * Spec. Timing */
> +/* * SD3.0 */
> +/* * Fcclk Tcclk Fsclk Tsclk Tis Tih odly RTis RTih */
> +/* * 400K 2.5us 24M 41ns 5ns 5ns 1 2209ns 41ns */
> +/* * 25M 40ns 600M 1.67ns 5ns 5ns 3 14.99ns 5.01ns */
> +/* * 50M 20ns 600M 1.67ns 6ns 2ns 3 14.99ns 5.01ns */
> +/* * 50MDDR 20ns 600M 1.67ns 6ns 0.8ns 2 6.67ns 3.33ns */
> +/* * 104M 9.6ns 600M 1.67ns 3ns 0.8ns 1 7.93ns 1.67ns */
> +/* * 208M 4.8ns 600M 1.67ns 1.4ns 0.8ns 1 3.33ns 1.67ns */
> +
> +/* * 25M 40ns 300M 3.33ns 5ns 5ns 2 13.34ns 6.66ns */
> +/* * 50M 20ns 300M 3.33ns 6ns 2ns 2 13.34ns 6.66ns */
> +/* * 50MDDR 20ns 300M 3.33ns 6ns 0.8ns 1 6.67ns 3.33ns */
> +/* * 104M 9.6ns 300M 3.33ns 3ns 0.8ns 0 7.93ns 1.67ns */
> +/* * 208M 4.8ns 300M 3.33ns 1.4ns 0.8ns 0 3.13ns 1.67ns */
> +
> +/* * eMMC4.5 */
> +/* * 400K 2.5us 24M 41ns 3ns 3ns 1 2209ns 41ns */
> +/* * 25M 40ns 600M 1.67ns 3ns 3ns 3 14.99ns 5.01ns */
> +/* * 50M 20ns 600M 1.67ns 3ns 3ns 3 14.99ns 5.01ns */
> +/* * 50MDDR 20ns 600M 1.67ns 2.5ns 2.5ns 2 6.67ns 3.33ns */
> +/* * 200M 5ns 600M 1.67ns 1.4ns 0.8ns 1 3.33ns 1.67ns */
> +/* *\/ */

It seems a bit silly to copy all the above data from the specs, I
don't think it's needed.

> +
> +static void sunxi_mmc_init_idma_des(struct sunxi_mmc_host *host,
> + struct mmc_data *data)
> +{
> + struct sunxi_idma_des *pdes = (struct sunxi_idma_des *)host->sg_cpu;
> + struct sunxi_idma_des *pdes_pa = (struct sunxi_idma_des *)host->sg_dma;
> + int i, max_len = (1 << host->idma_des_size_bits);
> +
> + for (i = 0; i < data->sg_len; i++) {
> + pdes[i].config = SDXC_IDMAC_DES0_CH | SDXC_IDMAC_DES0_OWN |
> + SDXC_IDMAC_DES0_DIC;
> +
> + if (data->sg[i].length == max_len)
> + pdes[i].buf_size = 0; /* 0 == max_len */
> + else
> + pdes[i].buf_size = data->sg[i].length;
> +
> + pdes[i].buf_addr_ptr1 = sg_dma_address(&data->sg[i]);
> + pdes[i].buf_addr_ptr2 = (u32)&pdes_pa[i + 1];
> + }
> +
> + pdes[0].config |= SDXC_IDMAC_DES0_FD;
> + pdes[i - 1].config = SDXC_IDMAC_DES0_OWN | SDXC_IDMAC_DES0_LD;
> +
> + /*
> + * Avoid the io-store starting the idmac hitting io-mem before the
> + * descriptors hit the main-mem.
> + */
> + wmb();
> +}
> +
> +static enum dma_data_direction sunxi_mmc_get_dma_dir(struct mmc_data *data)
> +{
> + if (data->flags & MMC_DATA_WRITE)
> + return DMA_TO_DEVICE;
> + else
> + return DMA_FROM_DEVICE;
> +}
> +
> +static int sunxi_mmc_map_dma(struct sunxi_mmc_host *smc_host,
> + struct mmc_data *data)
> +{
> + u32 i, dma_len;
> + struct scatterlist *sg;
> +
> + dma_len = dma_map_sg(mmc_dev(smc_host->mmc), data->sg, data->sg_len,
> + sunxi_mmc_get_dma_dir(data));
> + if (dma_len == 0) {
> + dev_err(mmc_dev(smc_host->mmc), "dma_map_sg failed\n");
> + return -ENOMEM;
> + }
> +
> + for_each_sg(data->sg, sg, data->sg_len, i) {
> + if (sg->offset & 3 || sg->length & 3) {
> + dev_err(mmc_dev(smc_host->mmc),
> + "unaligned scatterlist: os %x length %d\n",
> + sg->offset, sg->length);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void sunxi_mmc_start_dma(struct sunxi_mmc_host *smc_host,
> + struct mmc_data *data)
> +{
> + u32 rval;
> +
> + sunxi_mmc_init_idma_des(smc_host, data);
> +
> + rval = mci_readl(smc_host, REG_GCTRL);
> + rval |= SDXC_DMA_ENABLE_BIT;
> + mci_writel(smc_host, REG_GCTRL, rval);
> + rval |= SDXC_DMA_RESET;
> + mci_writel(smc_host, REG_GCTRL, rval);
> +
> + mci_writel(smc_host, REG_DMAC, SDXC_IDMAC_SOFT_RESET);
> +
> + if (!(data->flags & MMC_DATA_WRITE))
> + mci_writel(smc_host, REG_IDIE, SDXC_IDMAC_RECEIVE_INTERRUPT);
> +
> + mci_writel(smc_host, REG_DMAC,
> + SDXC_IDMAC_FIX_BURST | SDXC_IDMAC_IDMA_ON);
> +}
> +
> +static void sunxi_mmc_send_manual_stop(struct sunxi_mmc_host *host,
> + struct mmc_request *req)
> +{
> + u32 cmd_val = SDXC_START | SDXC_RESP_EXPIRE | SDXC_STOP_ABORT_CMD
> + | SDXC_CHECK_RESPONSE_CRC | MMC_STOP_TRANSMISSION;
> + u32 ri = 0;
> + unsigned long expire = jiffies + msecs_to_jiffies(1000);
> +
> + mci_writel(host, REG_CARG, 0);
> + mci_writel(host, REG_CMDR, cmd_val);
> +
> + do {
> + ri = mci_readl(host, REG_RINTR);
> + } while (!(ri & (SDXC_COMMAND_DONE | SDXC_INTERRUPT_ERROR_BIT)) &&
> + time_before(jiffies, expire));
> +
> + if (ri & SDXC_INTERRUPT_ERROR_BIT) {
> + dev_err(mmc_dev(host->mmc), "send stop command failed\n");
> + if (req->stop)
> + req->stop->resp[0] = -ETIMEDOUT;
> + } else {
> + if (req->stop)
> + req->stop->resp[0] = mci_readl(host, REG_RESP0);
> + }
> +
> + mci_writel(host, REG_RINTR, 0xffff);
> +}
> +
> +static void sunxi_mmc_dump_errinfo(struct sunxi_mmc_host *smc_host)
> +{
> + struct mmc_command *cmd = smc_host->mrq->cmd;
> + struct mmc_data *data = smc_host->mrq->data;
> +
> + /* For some cmds timeout is normal with sd/mmc cards */
> + if ((smc_host->int_sum & SDXC_INTERRUPT_ERROR_BIT) ==
> + SDXC_RESP_TIMEOUT && (cmd->opcode == SD_IO_SEND_OP_COND ||
> + cmd->opcode == SD_IO_RW_DIRECT))
> + return;
> +
> + dev_err(mmc_dev(smc_host->mmc),
> + "smc %d err, cmd %d,%s%s%s%s%s%s%s%s%s%s !!\n",
> + smc_host->mmc->index, cmd->opcode,
> + data ? (data->flags & MMC_DATA_WRITE ? " WR" : " RD") : "",
> + smc_host->int_sum & SDXC_RESP_ERROR ? " RE" : "",
> + smc_host->int_sum & SDXC_RESP_CRC_ERROR ? " RCE" : "",
> + smc_host->int_sum & SDXC_DATA_CRC_ERROR ? " DCE" : "",
> + smc_host->int_sum & SDXC_RESP_TIMEOUT ? " RTO" : "",
> + smc_host->int_sum & SDXC_DATA_TIMEOUT ? " DTO" : "",
> + smc_host->int_sum & SDXC_FIFO_RUN_ERROR ? " FE" : "",
> + smc_host->int_sum & SDXC_HARD_WARE_LOCKED ? " HL" : "",
> + smc_host->int_sum & SDXC_START_BIT_ERROR ? " SBE" : "",
> + smc_host->int_sum & SDXC_END_BIT_ERROR ? " EBE" : ""
> + );
> +}
> +
> +/* Called in interrupt context! */
> +static int sunxi_mmc_finalize_request(struct sunxi_mmc_host *host)
> +{
> + struct mmc_request *mrq = host->mrq;
> +
> + mci_writel(host, REG_IMASK, host->sdio_imask);
> + mci_writel(host, REG_IDIE, 0);
> +
> + if (host->int_sum & SDXC_INTERRUPT_ERROR_BIT) {
> + sunxi_mmc_dump_errinfo(host);
> + mrq->cmd->error = -ETIMEDOUT;
> +
> + if (mrq->data)
> + mrq->data->error = -ETIMEDOUT;
> +
> + if (mrq->stop)
> + mrq->stop->error = -ETIMEDOUT;
> + } else {
> + if (mrq->cmd->flags & MMC_RSP_136) {
> + mrq->cmd->resp[0] = mci_readl(host, REG_RESP3);
> + mrq->cmd->resp[1] = mci_readl(host, REG_RESP2);
> + mrq->cmd->resp[2] = mci_readl(host, REG_RESP1);
> + mrq->cmd->resp[3] = mci_readl(host, REG_RESP0);
> + } else {
> + mrq->cmd->resp[0] = mci_readl(host, REG_RESP0);
> + }
> +
> + if (mrq->data)
> + mrq->data->bytes_xfered =
> + mrq->data->blocks * mrq->data->blksz;
> + }
> +
> + if (mrq->data) {
> + struct mmc_data *data = mrq->data;
> + u32 rval;
> +
> + mci_writel(host, REG_IDST, 0x337);
> + mci_writel(host, REG_DMAC, 0);
> + rval = mci_readl(host, REG_GCTRL);
> + rval |= SDXC_DMA_RESET;
> + mci_writel(host, REG_GCTRL, rval);
> + rval &= ~SDXC_DMA_ENABLE_BIT;
> + mci_writel(host, REG_GCTRL, rval);
> + rval |= SDXC_FIFO_RESET;
> + mci_writel(host, REG_GCTRL, rval);
> + dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
> + sunxi_mmc_get_dma_dir(data));
> + }
> +
> + mci_writel(host, REG_RINTR, 0xffff);
> +
> + dev_dbg(mmc_dev(host->mmc), "req done, resp %08x %08x %08x %08x\n",
> + mrq->cmd->resp[0], mrq->cmd->resp[1],
> + mrq->cmd->resp[2], mrq->cmd->resp[3]);
> +
> + host->mrq = NULL;
> + host->int_sum = 0;
> + host->wait_dma = false;
> +
> + if (mrq->data && mrq->data->error) {
> + host->manual_stop_mrq = mrq;
> + tasklet_schedule(&host->manual_stop_tasklet);
> + return -EBUSY;
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t sunxi_mmc_irq(int irq, void *dev_id)
> +{
> + struct sunxi_mmc_host *host = dev_id;
> + struct mmc_request *mrq;
> + bool finalize = false;
> + bool complete = false;
> + bool sdio_int = false;
> + u32 msk_int;
> + u32 idma_int;
> +
> + spin_lock(&host->lock);
> +
> + idma_int = mci_readl(host, REG_IDST);
> + msk_int = mci_readl(host, REG_MISTA);
> +
> + dev_dbg(mmc_dev(host->mmc), "irq: rq %p mi %08x idi %08x\n",
> + host->mrq, msk_int, idma_int);
> +
> + mrq = host->mrq;
> + if (mrq) {
> + if (idma_int & SDXC_IDMAC_RECEIVE_INTERRUPT)
> + host->wait_dma = false;
> +
> + host->int_sum |= msk_int;
> +
> + /* Wait for COMMAND_DONE on RESPONSE_TIMEOUT before finalize */
> + if ((host->int_sum & SDXC_RESP_TIMEOUT) &&
> + !(host->int_sum & SDXC_COMMAND_DONE))
> + mci_writel(host, REG_IMASK,
> + host->sdio_imask | SDXC_COMMAND_DONE);
> + /* Don't wait for dma on error */
> + else if (host->int_sum & SDXC_INTERRUPT_ERROR_BIT)
> + finalize = true;
> + else if ((host->int_sum & SDXC_INTERRUPT_DONE_BIT) &&
> + !host->wait_dma)
> + finalize = true;
> + }
> +
> + if (msk_int & SDXC_SDIO_INTERRUPT)
> + sdio_int = true;
> +
> + mci_writel(host, REG_RINTR, msk_int);
> + mci_writel(host, REG_IDST, idma_int);
> +
> + if (finalize) {
> + if (sunxi_mmc_finalize_request(host) == 0)
> + complete = true;
> + }
> +
> + spin_unlock(&host->lock);
> +
> + if (complete)
> + mmc_request_done(host->mmc, mrq);
> +
> + if (sdio_int)
> + mmc_signal_sdio_irq(host->mmc);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static void sunxi_mmc_manual_stop_tasklet(unsigned long data)
> +{
> + struct sunxi_mmc_host *host = (struct sunxi_mmc_host *) data;
> + struct mmc_request *mrq;
> + unsigned long iflags;
> +
> + spin_lock_irqsave(&host->lock, iflags);
> + mrq = host->manual_stop_mrq;
> + spin_unlock_irqrestore(&host->lock, iflags);
> +
> + if (!mrq) {
> + dev_err(mmc_dev(host->mmc), "no request for manual stop\n");
> + return;
> + }
> +
> + dev_err(mmc_dev(host->mmc), "data error, sending stop command\n");
> + sunxi_mmc_send_manual_stop(host, mrq);
> +
> + spin_lock_irqsave(&host->lock, iflags);
> + host->manual_stop_mrq = NULL;
> + spin_unlock_irqrestore(&host->lock, iflags);
> +
> + mmc_request_done(host->mmc, mrq);
> +}
> +
> +static void sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
> +{
> + unsigned long expire = jiffies + msecs_to_jiffies(2000);
> + u32 rval;
> +
> + rval = mci_readl(host, REG_CLKCR);
> + rval &= ~(SDXC_CARD_CLOCK_ON | SDXC_LOW_POWER_ON);
> +
> + if (oclk_en)
> + rval |= SDXC_CARD_CLOCK_ON;
> +
> + mci_writel(host, REG_CLKCR, rval);
> +
> + rval = SDXC_START | SDXC_UPCLK_ONLY | SDXC_WAIT_PRE_OVER;
> + if (host->voltage_switching)
> + rval |= SDXC_VOLTAGE_SWITCH;
> + mci_writel(host, REG_CMDR, rval);
> +
> + do {
> + rval = mci_readl(host, REG_CMDR);
> + } while (time_before(jiffies, expire) && (rval & SDXC_START));
> +
> + if (rval & SDXC_START) {
> + dev_err(mmc_dev(host->mmc), "fatal err update clk timeout\n");
> + host->ferror = 1;
> + }
> +}
> +
> +static void sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *smc_host,
> + unsigned int rate)
> +{
> + u32 newrate, oclk_dly, rval, sclk_dly, src_clk;
> + struct clk_hw *hw = __clk_get_hw(smc_host->clk_mod);
> +
> + newrate = clk_round_rate(smc_host->clk_mod, rate);
> + if (smc_host->clk_mod_rate == newrate) {
> + dev_dbg(mmc_dev(smc_host->mmc), "clk already %d, rounded %d\n",
> + rate, newrate);
> + return;
> + }
> +
> + dev_dbg(mmc_dev(smc_host->mmc), "setting clk to %d, rounded %d\n",
> + rate, newrate);
> +
> + /* setting clock rate */
> + clk_set_rate(smc_host->clk_mod, newrate);
> + smc_host->clk_mod_rate = clk_get_rate(smc_host->clk_mod);
> + dev_dbg(mmc_dev(smc_host->mmc), "clk is now %d\n",
> + smc_host->clk_mod_rate);
> +
> + sunxi_mmc_oclk_onoff(smc_host, 0);
> + /* clear internal divider */
> + rval = mci_readl(smc_host, REG_CLKCR);
> + rval &= ~0xff;
> + mci_writel(smc_host, REG_CLKCR, rval);
> +
> + /* determine delays */
> + if (rate <= 400000) {
> + oclk_dly = 0;
> + sclk_dly = 7;
> + } else if (rate <= 25000000) {
> + oclk_dly = 0;
> + sclk_dly = 5;
> + } else if (rate <= 50000000) {
> + if (smc_host->ddr) {
> + oclk_dly = 2;
> + sclk_dly = 4;
> + } else {
> + oclk_dly = 3;
> + sclk_dly = 5;
> + }
> + } else {
> + /* rate > 50000000 */
> + oclk_dly = 2;
> + sclk_dly = 4;
> + }
> +
> + src_clk = clk_get_rate(clk_get_parent(smc_host->clk_mod));
> + if (src_clk >= 300000000 && src_clk <= 400000000) {
> + if (oclk_dly)
> + oclk_dly--;
> + if (sclk_dly)
> + sclk_dly--;
> + }
> +
> + clk_sunxi_mmc_phase_control(hw, sclk_dly, oclk_dly);
> + sunxi_mmc_oclk_onoff(smc_host, 1);
> +
> + /* oclk_onoff sets various irq status bits, clear these */
> + mci_writel(smc_host, REG_RINTR,
> + mci_readl(smc_host, REG_RINTR) & ~SDXC_SDIO_INTERRUPT);
> +}
> +
> +static void sunxi_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct sunxi_mmc_host *host = mmc_priv(mmc);
> + u32 rval;
> + s32 err;
> +
> + /* Set the power state */
> + switch (ios->power_mode) {
> + case MMC_POWER_ON:
> + break;
> +
> + case MMC_POWER_UP:
> + if (!IS_ERR(host->vmmc)) {
> + mmc_regulator_set_ocr(host->mmc, host->vmmc, ios->vdd);
> + udelay(200);
> + }
> +
> + err = sunxi_mmc_init_host(mmc);

So, sunxi_mmc_init_host() will ungate the clocks - but you shouldn't
use ->set_ios() callback to implement power save.

Clocks should be ungated at ->probe() and gated at ->remove().

If fine grained power save is wanted, I advise you to rework the clock
handling - and to build it upon runtime PM instead. Typically you
would do these adaptations:

1. Besides enabling the clocks at ->probe(), also enable runtime PM
and use the runtime PM auto-suspend feature.
2. Add pm_runtime_get|put at the proper places in the driver.
3. Implement the runtime PM callbacks (suspend|resume) and do clock
gating|ungating from there.

You may refer to drivers/mmc/host/mmci.c to get an example.

> + if (err) {
> + host->ferror = 1;
> + return;
> + }
> +
> + enable_irq(host->irq);
> +
> + dev_dbg(mmc_dev(host->mmc), "power on!\n");
> + host->ferror = 0;
> + break;
> +
> + case MMC_POWER_OFF:
> + dev_dbg(mmc_dev(host->mmc), "power off!\n");
> + disable_irq(host->irq);
> + sunxi_mmc_exit_host(host);

See comment above for sunxi_mmc_init_host().

> + if (!IS_ERR(host->vmmc))
> + mmc_regulator_set_ocr(host->mmc, host->vmmc, 0);
> +
> + host->ferror = 0;
> + break;
> + }
> +
> + /* set bus width */
> + switch (ios->bus_width) {
> + case MMC_BUS_WIDTH_1:
> + mci_writel(host, REG_WIDTH, SDXC_WIDTH1);
> + host->bus_width = 1;
> + break;
> + case MMC_BUS_WIDTH_4:
> + mci_writel(host, REG_WIDTH, SDXC_WIDTH4);
> + host->bus_width = 4;
> + break;
> + case MMC_BUS_WIDTH_8:
> + mci_writel(host, REG_WIDTH, SDXC_WIDTH8);
> + host->bus_width = 8;
> + break;
> + }
> +
> + /* set ddr mode */
> + rval = mci_readl(host, REG_GCTRL);
> + if (ios->timing == MMC_TIMING_UHS_DDR50) {
> + rval |= SDXC_DDR_MODE;
> + host->ddr = 1;
> + } else {
> + rval &= ~SDXC_DDR_MODE;
> + host->ddr = 0;
> + }
> + mci_writel(host, REG_GCTRL, rval);
> +
> + /* set up clock */
> + if (ios->clock && ios->power_mode) {
> + dev_dbg(mmc_dev(host->mmc), "ios->clock: %d\n", ios->clock);
> + sunxi_mmc_clk_set_rate(host, ios->clock);
> + usleep_range(50000, 55000);

Is those values for usleep really correct? I am not sure how many
times we execute this path while detecting/powering the card, but
quite a few.
Detecting/powering the card is also done during each system
suspend/resume cycle - thus this will heavily affect these cycles.

> + }
> +}
> +
> +static void sunxi_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
> +{
> + struct sunxi_mmc_host *smc_host = mmc_priv(mmc);
> + unsigned long flags;
> + u32 imask;
> +
> + spin_lock_irqsave(&smc_host->lock, flags);
> +
> + imask = mci_readl(smc_host, REG_IMASK);
> + if (enable) {
> + smc_host->sdio_imask = SDXC_SDIO_INTERRUPT;
> + imask |= SDXC_SDIO_INTERRUPT;
> + } else {
> + smc_host->sdio_imask = 0;
> + imask &= ~SDXC_SDIO_INTERRUPT;
> + }
> + mci_writel(smc_host, REG_IMASK, imask);
> + spin_unlock_irqrestore(&smc_host->lock, flags);
> +}
> +
> +static void sunxi_mmc_hw_reset(struct mmc_host *mmc)
> +{
> + struct sunxi_mmc_host *smc_host = mmc_priv(mmc);
> + mci_writel(smc_host, REG_HWRST, 0);
> + udelay(10);
> + mci_writel(smc_host, REG_HWRST, 1);
> + udelay(300);
> +}
> +
> +static void sunxi_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
> +{
> + struct sunxi_mmc_host *host = mmc_priv(mmc);
> + struct mmc_command *cmd = mrq->cmd;
> + struct mmc_data *data = mrq->data;
> + unsigned long iflags;
> + u32 imask = SDXC_INTERRUPT_ERROR_BIT;
> + u32 cmd_val = SDXC_START | (cmd->opcode & 0x3f);
> + int ret;
> +
> + if (!mmc_gpio_get_cd(mmc) || host->ferror) {

I wouldn't recommend to read the state of a gpio pin before you start
serving requests, since it will add a latency for each of them.

I believe a better idea is to let the driver handle the errors that
may occur during the transfer - and just report them upwards in the
mmc stack. The mmc core should detect the card to be removed anyway.

> + dev_dbg(mmc_dev(host->mmc), "no medium present\n");
> + mrq->cmd->error = -ENOMEDIUM;
> + mmc_request_done(mmc, mrq);
> + return;
> + }
> +
> + if (data) {
> + ret = sunxi_mmc_map_dma(host, data);
> + if (ret < 0) {
> + dev_err(mmc_dev(host->mmc), "map DMA failed\n");
> + cmd->error = ret;
> + cmd->data->error = ret;
> + mmc_request_done(host->mmc, mrq);
> + return;
> + }
> + }
> +
> + if (cmd->opcode == MMC_GO_IDLE_STATE) {
> + cmd_val |= SDXC_SEND_INIT_SEQUENCE;
> + imask |= SDXC_COMMAND_DONE;

This seems really strange! Please elaborate on why need specific
handling of this CMD.

> + }
> +
> + if (cmd->opcode == SD_SWITCH_VOLTAGE) {

This won't work!

You must implement ->start_signal_voltage_switch() to follow spec and
support UHS cards.
Additionally your ->set_ios() shall support to gate the clock to the
card, while the frequency is 0.

Optionally, you may implement ->card_busy().

> + cmd_val |= SDXC_VOLTAGE_SWITCH;
> + imask |= SDXC_VOLTAGE_CHANGE_DONE;
> + host->voltage_switching = 1;
> + sunxi_mmc_oclk_onoff(host, 1);
> + }
> +
> + if (cmd->flags & MMC_RSP_PRESENT) {
> + cmd_val |= SDXC_RESP_EXPIRE;
> + if (cmd->flags & MMC_RSP_136)
> + cmd_val |= SDXC_LONG_RESPONSE;
> + if (cmd->flags & MMC_RSP_CRC)
> + cmd_val |= SDXC_CHECK_RESPONSE_CRC;
> +
> + if ((cmd->flags & MMC_CMD_MASK) == MMC_CMD_ADTC) {
> + cmd_val |= SDXC_DATA_EXPIRE | SDXC_WAIT_PRE_OVER;
> + if (cmd->data->flags & MMC_DATA_STREAM) {
> + imask |= SDXC_AUTO_COMMAND_DONE;
> + cmd_val |= SDXC_SEQUENCE_MODE |
> + SDXC_SEND_AUTO_STOP;
> + }
> +
> + if (cmd->data->stop) {
> + imask |= SDXC_AUTO_COMMAND_DONE;
> + cmd_val |= SDXC_SEND_AUTO_STOP;
> + } else {
> + imask |= SDXC_DATA_OVER;
> + }
> +
> + if (cmd->data->flags & MMC_DATA_WRITE)
> + cmd_val |= SDXC_WRITE;
> + else
> + host->wait_dma = true;
> + } else {
> + imask |= SDXC_COMMAND_DONE;
> + }
> + } else {
> + imask |= SDXC_COMMAND_DONE;
> + }
> +
> + dev_dbg(mmc_dev(host->mmc), "cmd %d(%08x) arg %x ie 0x%08x len %d\n",
> + cmd_val & 0x3f, cmd_val, cmd->arg, imask,
> + mrq->data ? mrq->data->blksz * mrq->data->blocks : 0);
> +
> + spin_lock_irqsave(&host->lock, iflags);
> +
> + if (host->mrq || host->manual_stop_mrq) {
> + spin_unlock_irqrestore(&host->lock, iflags);
> +
> + if (data)
> + dma_unmap_sg(mmc_dev(host->mmc), data->sg,
> + data->sg_len, sunxi_mmc_get_dma_dir(data));
> +
> + dev_err(mmc_dev(host->mmc), "request already pending\n");
> + mrq->cmd->error = -EBUSY;
> + mmc_request_done(host->mmc, mrq);
> + return;
> + }
> +
> + if (data) {
> + mci_writel(host, REG_BLKSZ, data->blksz);
> + mci_writel(host, REG_BCNTR, data->blksz * data->blocks);
> + sunxi_mmc_start_dma(host, data);
> + }
> +
> + host->mrq = mrq;
> + mci_writel(host, REG_IMASK, host->sdio_imask | imask);
> + mci_writel(host, REG_CARG, cmd->arg);
> + mci_writel(host, REG_CMDR, cmd_val);
> +
> + spin_unlock_irqrestore(&host->lock, iflags);
> +}
> +
> +static const struct of_device_id sunxi_mmc_of_match[] = {
> + { .compatible = "allwinner,sun4i-a10-mmc", },
> + { .compatible = "allwinner,sun5i-a13-mmc", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, sunxi_mmc_of_match);
> +
> +static struct mmc_host_ops sunxi_mmc_ops = {
> + .request = sunxi_mmc_request,
> + .set_ios = sunxi_mmc_set_ios,
> + .get_ro = mmc_gpio_get_ro,
> + .get_cd = mmc_gpio_get_cd,
> + .enable_sdio_irq = sunxi_mmc_enable_sdio_irq,
> + .hw_reset = sunxi_mmc_hw_reset,
> +};
> +
> +static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
> + struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + int ret;
> +
> + if (of_device_is_compatible(np, "allwinner,sun4i-a10-mmc"))
> + host->idma_des_size_bits = 13;
> + else
> + host->idma_des_size_bits = 16;
> +
> + host->vmmc = devm_regulator_get_optional(&pdev->dev, "vmmc");
> + if (IS_ERR(host->vmmc) && PTR_ERR(host->vmmc) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> +
> + host->reg_base = devm_ioremap_resource(&pdev->dev,
> + platform_get_resource(pdev, IORESOURCE_MEM, 0));
> + if (IS_ERR(host->reg_base))
> + return PTR_ERR(host->reg_base);
> +
> + host->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
> + if (IS_ERR(host->clk_ahb)) {
> + dev_err(&pdev->dev, "Could not get ahb clock\n");
> + return PTR_ERR(host->clk_ahb);
> + }
> +
> + host->clk_mod = devm_clk_get(&pdev->dev, "mmc");
> + if (IS_ERR(host->clk_mod)) {
> + dev_err(&pdev->dev, "Could not get mod clock\n");
> + return PTR_ERR(host->clk_mod);
> + }
> +
> + host->reset = devm_reset_control_get(&pdev->dev, "ahb");
> + if (IS_ERR(host->reset))
> + host->reset = NULL; /* Having a reset controller is optional */
> +
> + /*
> + * Sometimes the controller asserts the irq on boot for some reason,
> + * and since it is not clocked there is no way to clear it. So make
> + * sure the controller is in a sane state before enabling irqs.
> + */
> + ret = sunxi_mmc_init_host(host->mmc);
> + if (ret)
> + return ret;
> +
> + host->irq = platform_get_irq(pdev, 0);
> + ret = devm_request_irq(&pdev->dev, host->irq, sunxi_mmc_irq, 0,
> + "sunxi-mmc", host);
> + if (ret == 0)
> + disable_irq(host->irq);
> +
> + /* And disable the controller again */
> + sunxi_mmc_exit_host(host);
> +
> + return ret;
> +}
> +
> +static int sunxi_mmc_probe(struct platform_device *pdev)
> +{
> + struct sunxi_mmc_host *host;
> + struct mmc_host *mmc;
> + int ret;
> +
> + mmc = mmc_alloc_host(sizeof(struct sunxi_mmc_host), &pdev->dev);
> + if (!mmc) {
> + dev_err(&pdev->dev, "mmc alloc host failed\n");
> + return -ENOMEM;
> + }
> +
> + host = mmc_priv(mmc);
> + host->mmc = mmc;
> + spin_lock_init(&host->lock);
> + tasklet_init(&host->manual_stop_tasklet,
> + sunxi_mmc_manual_stop_tasklet, (unsigned long)host);
> +
> + ret = sunxi_mmc_resource_request(host, pdev);
> + if (ret)
> + goto error_free_host;
> +
> + host->sg_cpu = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
> + &host->sg_dma, GFP_KERNEL);
> + if (!host->sg_cpu) {
> + dev_err(&pdev->dev, "Failed to allocate DMA descriptor mem\n");
> + ret = -ENOMEM;
> + goto error_free_host;
> + }
> +
> + mmc->ops = &sunxi_mmc_ops;
> + mmc->max_blk_count = 8192;
> + mmc->max_blk_size = 4096;
> + mmc->max_segs = PAGE_SIZE / sizeof(struct sunxi_idma_des);
> + mmc->max_seg_size = (1 << host->idma_des_size_bits);
> + mmc->max_req_size = mmc->max_seg_size * mmc->max_segs;
> + /* 400kHz ~ 50MHz */
> + mmc->f_min = 400000;
> + mmc->f_max = 50000000;
> + /* available voltages */
> + if (!IS_ERR(host->vmmc))
> + mmc->ocr_avail = mmc_regulator_get_ocrmask(host->vmmc);
> + else
> + mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
> +
> + mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED;
> + mmc->caps2 |= MMC_CAP2_NO_PRESCAN_POWERUP;

Are you sure you can enable this cap for all hosts/cards?

There are potential of breaking eMMC devices which has been powered
during boot and unless you can fully reset/power cycle them.

> +
> + ret = mmc_of_parse(mmc);
> + if (ret)
> + goto error_free_dma;
> +
> + ret = mmc_add_host(mmc);
> + if (ret)
> + goto error_free_dma;
> +
> + dev_info(&pdev->dev, "base:0x%p irq:%u\n", host->reg_base, host->irq);
> + platform_set_drvdata(pdev, mmc);
> + return 0;
> +
> +error_free_dma:
> + dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
> +error_free_host:
> + mmc_free_host(mmc);
> + return ret;
> +}
> +
> +static int sunxi_mmc_remove(struct platform_device *pdev)
> +{
> + struct mmc_host *mmc = platform_get_drvdata(pdev);
> + struct sunxi_mmc_host *host = mmc_priv(mmc);
> +
> + mmc_remove_host(mmc);
> + sunxi_mmc_exit_host(host);
> + tasklet_disable(&host->manual_stop_tasklet);
> + dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
> + mmc_free_host(mmc);
> +
> + return 0;
> +}
> +
> +static struct platform_driver sunxi_mmc_driver = {
> + .driver = {
> + .name = "sunxi-mmc",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(sunxi_mmc_of_match),
> + },
> + .probe = sunxi_mmc_probe,
> + .remove = sunxi_mmc_remove,
> +};
> +module_platform_driver(sunxi_mmc_driver);
> +
> +MODULE_DESCRIPTION("Allwinner's SD/MMC Card Controller Driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("David Lanzend?rfer <david.lanzendoerfer@o2s.ch>");
> +MODULE_ALIAS("platform:sunxi-mmc");
> --
> 1.9.0
>

Kind regards
Ulf Hansson