Re: [PATCH V5] mmc:host:sdhci-pci:Addition of Arasan PCI Controller with integrated phy.

From: Adrian Hunter
Date: Tue Dec 19 2017 - 07:19:28 EST


On 12/12/17 19:02, Atul Garg wrote:
> The Arasan Controller is based on a FPGA platform and has integrated phy
> with specific registers used during initialization and
> management of different modes. The phy and the controller are integrated
> and registers are very specific to Arasan.
>
> Arasan being an IP provider, licenses these IPs to various companies for
> integration of IP in custom SOCs. The custom SOCs define own register
> map depending on how bits are tied inside the SOC for phy registers,
> depending on SOC memory plan and hence will require own platform drivers.
>
> If more details on phy regsiters are required, an interface document is
> hosted at https: //arasandotcom/NF/eMMC5.1 PHY Programming in Linux.pdf.
>
> Signed-off-by: Atul Garg <agarg@xxxxxxxxxx>

Sorry for the slow reply. Looks good. Some very minor comments below.
Also I had trouble applying it so it would be good to have a new version
based on the latest mmc next.

> ---
> V5 - Separated arasan_phy_poll function into arasan_phy_addr_poll and
> arasan_phy_sts_poll Tabspace corrected. Checked return values of poll functions.
> Removed static declaration of sdhci_pci_enable_dma and defined in
> sdhci-pci.h as suggested by Adrian Hunter <adrian.hunter@xxxxxxxxx>.
> V4 - Created arasan_phy_poll function to have common timeout call.
> .Restructured arasan_set_phy to arasan_select_phy_clock and
> .arasan_phy_set to have single set of registers to be programmed for different modes.
> .Applied code style suggestions from Adrian Hunter <adrian.hunter@xxxxxxxxx>.
> V3 - Removed sdhci-pci-arasan.h. Code and interface document mentioned
> above are made relevant..Applied code style suggestions from
> Sekhar Nori <nsekhar@xxxxxx> and .Adrian Hunter <adrian.hunter@xxxxxxxxx>.
> V2 - Removed code from sdhci-pci-core.c and created sdhci-pci-arasan.c and
> .sdhci-pci-arasan.h.
> V1 - Initial Patch coded in sdhci-pci-core.c.
>
> drivers/mmc/host/Makefile | 2 +-
> drivers/mmc/host/sdhci-pci-arasan.c | 341 ++++++++++++++++++++++++++++++++++++
> drivers/mmc/host/sdhci-pci-core.c | 4 +-
> drivers/mmc/host/sdhci-pci.h | 7 +-
> 4 files changed, 350 insertions(+), 4 deletions(-)
> create mode 100644 drivers/mmc/host/sdhci-pci-arasan.c
>
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index ab61a3e..6781b81 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -10,7 +10,7 @@ obj-$(CONFIG_MMC_MXC) += mxcmmc.o
> obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
> obj-$(CONFIG_MMC_SDHCI) += sdhci.o
> obj-$(CONFIG_MMC_SDHCI_PCI) += sdhci-pci.o
> -sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o
> +sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o sdhci-pci-arasan.o
> obj-$(subst m,y,$(CONFIG_MMC_SDHCI_PCI)) += sdhci-pci-data.o
> obj-$(CONFIG_MMC_SDHCI_ACPI) += sdhci-acpi.o
> obj-$(CONFIG_MMC_SDHCI_PXAV3) += sdhci-pxav3.o
> diff --git a/drivers/mmc/host/sdhci-pci-arasan.c b/drivers/mmc/host/sdhci-pci-arasan.c
> new file mode 100644
> index 0000000..9df64a1
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-pci-arasan.c
> @@ -0,0 +1,341 @@
> +/*
> + * Copyright (C) 2017 Arasan Chip Systems Inc.
> + *
> + * Author: Atul Garg <agarg@xxxxxxxxxx>
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * 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.
> + */
> +
> +#include <linux/pci.h>
> +#include <linux/delay.h>
> +
> +#include "sdhci.h"
> +#include "sdhci-pci.h"
> +
> +/* Extra registers for Arasan SD Host Controller for eMMC5.1 PHY */
> +#define PHY_ADDR_REG 0x300
> +#define PHY_DAT_REG 0x304
> +
> +#define PHY_WRITE BIT(8)
> +#define PHY_BUSY BIT(9)
> +#define DATA_MASK 0xFF
> +
> +/* eMMC5.1 PHY Specific Registers */
> +#define DLL_STS 0x00
> +#define IPAD_CTRL1 0x01
> +#define IPAD_CTRL2 0x02
> +#define IPAD_STS 0x03
> +#define IOREN_CTRL1 0x06
> +#define IOREN_CTRL2 0x07
> +#define IOPU_CTRL1 0x08
> +#define IOPU_CTRL2 0x09
> +#define ITAP_DELAY 0x0C
> +#define OTAP_DELAY 0x0D
> +#define STRB_SEL 0x0E
> +#define CLKBUF_SEL 0x0F
> +#define MODE_CTRL 0x11
> +#define DLL_TRIM 0x12
> +#define CMD_CTRL 0x20
> +#define DATA_CTRL 0x21
> +#define STRB_CTRL 0x22
> +#define CLK_CTRL 0x23
> +#define PHY_CTRL 0x24
> +
> +#define DLL_EN BIT(3)
> +#define RTRIM_EN BIT(1)
> +#define PDB_EN BIT(1)
> +#define RETB_EN BIT(6)
> +#define ODEN_CMD BIT(1)
> +#define ODEN_DAT 0xFF
> +#define REN_STRB BIT(0)
> +#define REN_CMD BIT(1)
> +#define REN_DAT 0xFF
> +#define PU_CMD BIT(1)
> +#define PU_DAT 0xFF
> +#define ITAPDLY_EN BIT(0)
> +#define OTAPDLY_EN BIT(0)
> +#define OD_REL_CMD BIT(1)
> +#define OD_REL_DAT 0xFF
> +#define DLLTRM_ICP 0x8
> +#define PDB_CMD BIT(0)
> +#define PDB_DAT 0xFF
> +#define PDB_STRB BIT(0)
> +#define PDB_CLK BIT(0)
> +#define CALDONE_MASK 0x10
> +#define DLL_RDY_MASK 0x10
> +#define MAX_CLK_BUF 0x7
> +
> +/* Mode Controls */
> +#define ENHSTRB_MODE BIT(0)
> +#define HS400_MODE BIT(1)
> +#define LEGACY_MODE BIT(2)
> +#define DDR50_MODE BIT(3)
> +
> +/*
> + * Controller has no specific bits for HS/HS200.
> + * Used BIT(4), BIT(5) for software programming.
> + */
> +#define HS200_MODE BIT(4)
> +#define HS_MODE BIT(5)

The defines still don't line up. They should line up in the source code
when the tab width is set to 8.

> +
> +#define OTAPDLY(x) ((x << 1) | OTAPDLY_EN)
> +#define ITAPDLY(x) ((x << 1) | ITAPDLY_EN)
> +#define FREQSEL(x) ((x << 5) | DLL_EN)
> +#define IOPAD(x, y) ((x) | (y << 2))

Some tools get upset if they see macros where the parameters are not
enclosed in parentheses i.e. should be:

#define OTAPDLY(x) (((x) << 1) | OTAPDLY_EN)
#define ITAPDLY(x) (((x) << 1) | ITAPDLY_EN)
#define FREQSEL(x) (((x) << 5) | DLL_EN)
#define IOPAD(x, y) ((x) | ((y) << 2))

> +
> +/* Arasan private data */
> +struct arasan_host {
> + u32 chg_clk;
> +};
> +
> +static int arasan_phy_addr_poll(struct sdhci_host *host, u32 offset, u32 mask)
> +{
> + ktime_t timeout = ktime_add_us(ktime_get(), 100);
> + bool failed;
> + u8 val = 0;
> +
> + while (1) {
> + failed = ktime_after(ktime_get(), timeout);
> + val = sdhci_readw(host, PHY_ADDR_REG);
> + if (!(val & mask))
> + return 0;
> + if (failed)
> + return -EBUSY;
> + }
> +}
> +
> +static int arasan_phy_write(struct sdhci_host *host, u8 data, u8 offset)
> +{
> + int ret;
> +
> + sdhci_writew(host, data, PHY_DAT_REG);
> + sdhci_writew(host, (PHY_WRITE | offset), PHY_ADDR_REG);
> + ret = arasan_phy_addr_poll(host, PHY_ADDR_REG, PHY_BUSY);
> + return ret;

Should be just:

return arasan_phy_addr_poll(host, PHY_ADDR_REG, PHY_BUSY);

Then ret is not needed.

> +}
> +
> +static int arasan_phy_read(struct sdhci_host *host, u8 offset, u8 *data)
> +{
> + int ret;
> +
> + sdhci_writew(host, 0, PHY_DAT_REG);
> + sdhci_writew(host, offset, PHY_ADDR_REG);
> + ret = arasan_phy_addr_poll(host, PHY_ADDR_REG, PHY_BUSY);
> +
> + /* Masking valid data bits */
> + *data = sdhci_readw(host, PHY_DAT_REG) & DATA_MASK;
> + return ret;
> +}
> +
> +static int arasan_phy_sts_poll(struct sdhci_host *host, u32 offset, u32 mask)
> +{
> + int ret;
> + ktime_t timeout = ktime_add_us(ktime_get(), 100);
> + bool failed;
> + u8 val = 0;
> +
> + while (1) {
> + failed = ktime_after(ktime_get(), timeout);
> + ret = arasan_phy_read(host, offset, &val);
> + if (ret)
> + return -EBUSY;
> + else if (val & mask)
> + return 0;
> + if (failed)
> + return -EBUSY;
> + }
> +}
> +
> +/* Initialize the Arasan PHY */
> +static int arasan_phy_init(struct sdhci_host *host)
> +{
> + int ret;
> + u8 val;
> +
> + /* Program IOPADs and wait for calibration to be done */
> + if (arasan_phy_read(host, IPAD_CTRL1, &val) ||
> + arasan_phy_write(host, val | RETB_EN | PDB_EN, IPAD_CTRL1) ||
> + arasan_phy_read(host, IPAD_CTRL2, &val) ||
> + arasan_phy_write(host, val | RTRIM_EN, IPAD_CTRL2))
> + return -EBUSY;
> + ret = arasan_phy_sts_poll(host, IPAD_STS, CALDONE_MASK);
> + if (ret)
> + return -EBUSY;
> +
> + /* Program CMD/Data lines */
> + if (arasan_phy_read(host, IOREN_CTRL1, &val) ||
> + arasan_phy_write(host, val | REN_CMD | REN_STRB, IOREN_CTRL1) ||
> + arasan_phy_read(host, IOPU_CTRL1, &val) ||
> + arasan_phy_write(host, val | PU_CMD, IOPU_CTRL1) ||
> + arasan_phy_read(host, CMD_CTRL, &val) ||
> + arasan_phy_write(host, val | PDB_CMD, CMD_CTRL) ||
> + arasan_phy_read(host, IOREN_CTRL2, &val) ||
> + arasan_phy_write(host, val | REN_DAT, IOREN_CTRL2) ||
> + arasan_phy_read(host, IOPU_CTRL2, &val) ||
> + arasan_phy_write(host, val | PU_DAT, IOPU_CTRL2) ||
> + arasan_phy_read(host, DATA_CTRL, &val) ||
> + arasan_phy_write(host, val | PDB_DAT, DATA_CTRL) ||
> + arasan_phy_read(host, STRB_CTRL, &val) ||
> + arasan_phy_write(host, val | PDB_STRB, STRB_CTRL) ||
> + arasan_phy_read(host, CLK_CTRL, &val) ||
> + arasan_phy_write(host, val | PDB_CLK, CLK_CTRL) ||
> + arasan_phy_read(host, CLKBUF_SEL, &val) ||
> + arasan_phy_write(host, val | MAX_CLK_BUF, CLKBUF_SEL) ||
> + arasan_phy_write(host, LEGACY_MODE, MODE_CTRL))
> + return -EBUSY;
> + return 0;
> +}
> +
> +/* Set Arasan PHY for different modes */
> +static int arasan_phy_set(struct sdhci_host *host, u8 mode, u8 otap,
> + u8 drv_type, u8 itap, u8 trim, u8 clk)
> +{
> + u8 val;
> + int ret;
> +
> + if (mode == HS_MODE || mode == HS200_MODE)
> + ret = arasan_phy_write(host, 0x0, MODE_CTRL);
> + else
> + ret = arasan_phy_write(host, mode, MODE_CTRL);
> + if (ret)
> + return ret;
> + if (mode == HS400_MODE || mode == HS200_MODE) {
> + ret = arasan_phy_read(host, IPAD_CTRL1, &val);
> + if (ret)
> + return ret;
> + ret = arasan_phy_write(host, IOPAD(val, drv_type), IPAD_CTRL1);
> + if (ret)
> + return ret;
> + }
> + if (mode == LEGACY_MODE) {
> + ret = arasan_phy_write(host, 0x0, OTAP_DELAY);
> + if (ret)
> + return ret;
> + ret = arasan_phy_write(host, 0x0, ITAP_DELAY);
> + } else {
> + ret = arasan_phy_write(host, OTAPDLY(otap), OTAP_DELAY);
> + if (ret)
> + return ret;
> + if (mode != HS200_MODE)
> + ret = arasan_phy_write(host, ITAPDLY(itap), ITAP_DELAY);
> + else
> + ret = arasan_phy_write(host, 0x0, ITAP_DELAY);
> + }
> + if (ret)
> + return ret;
> + if (mode != LEGACY_MODE) {
> + ret = arasan_phy_write(host, trim, DLL_TRIM);
> + if (ret)
> + return ret;
> + }
> + ret = arasan_phy_write(host, 0, DLL_STS);
> + if (ret)
> + return ret;
> + if (mode != LEGACY_MODE) {
> + ret = arasan_phy_write(host, FREQSEL(clk), DLL_STS);
> + if (ret)
> + return ret;
> + ret = arasan_phy_sts_poll(host, DLL_STS, DLL_RDY_MASK);
> + if (ret)
> + return -EBUSY;
> + }
> + return 0;
> +}
> +
> +static int arasan_select_phy_clock(struct sdhci_host *host)
> +{
> + struct sdhci_pci_slot *slot = sdhci_priv(host);
> + struct arasan_host *arasan_host = sdhci_pci_priv(slot);
> + u8 clk;
> +
> + if (arasan_host->chg_clk == host->mmc->ios.clock)
> + return 0;
> +
> + arasan_host->chg_clk = host->mmc->ios.clock;
> + if (host->mmc->ios.clock == 200000000)
> + clk = 0x0;
> + else if (host->mmc->ios.clock == 100000000)
> + clk = 0x2;
> + else if (host->mmc->ios.clock == 50000000)
> + clk = 0x1;
> + else
> + clk = 0x0;
> +
> + if (host->mmc_host_ops.hs400_enhanced_strobe) {
> + arasan_phy_set(host, ENHSTRB_MODE, 1, 0x0, 0x0,
> + DLLTRM_ICP, clk);
> + } else {
> + switch (host->mmc->ios.timing) {
> + case MMC_TIMING_LEGACY:
> + arasan_phy_set(host, LEGACY_MODE, 0x0, 0x0, 0x0,
> + 0x0, 0x0);
> + break;
> + case MMC_TIMING_MMC_HS:
> + case MMC_TIMING_SD_HS:
> + arasan_phy_set(host, HS_MODE, 0x3, 0x0, 0x2,
> + DLLTRM_ICP, clk);
> + break;
> + case MMC_TIMING_MMC_HS200:
> + case MMC_TIMING_UHS_SDR104:
> + arasan_phy_set(host, HS200_MODE, 0x2,
> + host->mmc->ios.drv_type, 0x0,
> + DLLTRM_ICP, clk);
> + break;
> + case MMC_TIMING_MMC_DDR52:
> + case MMC_TIMING_UHS_DDR50:
> + arasan_phy_set(host, DDR50_MODE, 0x1, 0x0,
> + 0x0, DLLTRM_ICP, clk);
> + break;
> + case MMC_TIMING_MMC_HS400:
> + arasan_phy_set(host, HS400_MODE, 0x1,
> + host->mmc->ios.drv_type, 0xa,
> + DLLTRM_ICP, clk);
> + break;
> + default:
> + break;
> + }
> + }
> + return 0;
> +}
> +
> +static int arasan_pci_probe_slot(struct sdhci_pci_slot *slot)
> +{
> + int err;
> +
> + slot->host->mmc->caps |= MMC_CAP_NONREMOVABLE | MMC_CAP_8_BIT_DATA;
> + err = arasan_phy_init(slot->host);
> + if (err)
> + return -ENODEV;
> + return 0;
> +}
> +
> +static void arasan_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> + sdhci_set_clock(host, clock);
> +
> + /* Change phy settings for the new clock */
> + arasan_select_phy_clock(host);
> +}
> +
> +static const struct sdhci_ops arasan_sdhci_pci_ops = {
> + .set_clock = arasan_sdhci_set_clock,
> + .enable_dma = sdhci_pci_enable_dma,
> + .set_bus_width = sdhci_set_bus_width,
> + .reset = sdhci_reset,
> + .set_uhs_signaling = sdhci_set_uhs_signaling,
> +};
> +
> +const struct sdhci_pci_fixes sdhci_arasan = {
> + .probe_slot = arasan_pci_probe_slot,
> + .ops = &arasan_sdhci_pci_ops,
> + .priv_size = sizeof(struct arasan_host),
> +};
> +
> diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
> index 3e4f04f..fc2859f 100644
> --- a/drivers/mmc/host/sdhci-pci-core.c
> +++ b/drivers/mmc/host/sdhci-pci-core.c
> @@ -33,7 +33,6 @@
> #include "sdhci.h"
> #include "sdhci-pci.h"
>
> -static int sdhci_pci_enable_dma(struct sdhci_host *host);
> static void sdhci_pci_hw_reset(struct sdhci_host *host);
>
> #ifdef CONFIG_PM_SLEEP
> @@ -1306,6 +1305,7 @@ static const struct pci_device_id pci_ids[] = {
> SDHCI_PCI_DEVICE(O2, SDS1, o2),
> SDHCI_PCI_DEVICE(O2, SEABIRD0, o2),
> SDHCI_PCI_DEVICE(O2, SEABIRD1, o2),
> + SDHCI_PCI_DEVICE(ARASAN, PHY_EMMC, arasan),
> SDHCI_PCI_DEVICE_CLASS(AMD, SYSTEM_SDHCI, PCI_CLASS_MASK, amd),
> /* Generic SD host controller */
> {PCI_DEVICE_CLASS(SYSTEM_SDHCI, PCI_CLASS_MASK)},
> @@ -1320,7 +1320,7 @@ MODULE_DEVICE_TABLE(pci, pci_ids);
> * *
> \*****************************************************************************/
>
> -static int sdhci_pci_enable_dma(struct sdhci_host *host)
> +int sdhci_pci_enable_dma(struct sdhci_host *host)
> {
> struct sdhci_pci_slot *slot;
> struct pci_dev *pdev;
> diff --git a/drivers/mmc/host/sdhci-pci.h b/drivers/mmc/host/sdhci-pci.h
> index 063506c..657d8c6 100644
> --- a/drivers/mmc/host/sdhci-pci.h
> +++ b/drivers/mmc/host/sdhci-pci.h
> @@ -54,6 +54,9 @@
>
> #define PCI_SUBDEVICE_ID_NI_7884 0x7884
>
> +#define PCI_VENDOR_ID_ARASAN 0x16e6
> +#define PCI_DEVICE_ID_ARASAN_PHY_EMMC 0x0670

The defines still don't line up. They should line up in the source code
when the tab width is set to 8.

> +
> /*
> * PCI device class and mask
> */
> @@ -169,11 +172,13 @@ static inline void *sdhci_pci_priv(struct sdhci_pci_slot *slot)
> #ifdef CONFIG_PM_SLEEP
> int sdhci_pci_resume_host(struct sdhci_pci_chip *chip);
> #endif
> -
> +int sdhci_pci_enable_dma(struct sdhci_host *host);
> int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot);
> int sdhci_pci_o2_probe(struct sdhci_pci_chip *chip);
> #ifdef CONFIG_PM_SLEEP
> int sdhci_pci_o2_resume(struct sdhci_pci_chip *chip);
> #endif
>
> +extern const struct sdhci_pci_fixes sdhci_arasan;
> +
> #endif /* __SDHCI_PCI_H */
>