Re: [PATCH] mmc:host:sdhci-pci:V3-Addition of Arasan PCI Controller with integrated phy.

From: Adrian Hunter
Date: Mon Nov 06 2017 - 07:15:20 EST

On 30/10/17 21:10, 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 registers are required, an interface document is
> hosted at https: //arasandotcom/NF/eMMC5.1 PHY Programming in Linux.pdf.
>
> Changes from V2: Removed sdhci-pci-arasan.h. Code and document mentioned
> above are made relevant. Applied code style suggestions from
> Sekhar Nori <nsekhar@xxxxxx> and Adrian Hunter <adrian.hunter@xxxxxxxxx>.

Please put the version changes after the --- line.

Also please put the version correctly in the patch subject and use more
conventional prefixes i.e.

[PATCH V3] mmc: sdhci-pci: Addition of Arasan PCI Controller with integrated phy

>
> Signed-off-by: Atul Garg <agarg@xxxxxxxxxx>
> ---
> drivers/mmc/host/Makefile | 2 +-
> drivers/mmc/host/sdhci-pci-arasan.c | 369 ++++++++++++++++++++++++++++++++++++
> drivers/mmc/host/sdhci-pci-core.c | 14 ++
> drivers/mmc/host/sdhci-pci.h | 6 +
> 4 files changed, 390 insertions(+), 1 deletion(-)
> 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..a0a4f3e
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-pci-arasan.c
> @@ -0,0 +1,369 @@
> +/*
> + * Copyright (C) 2017 Arasan Chip Systems Inc.,
> + *
> + * Authors: 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 HOST_PHY_ADDR_REG 0x300
> +#define HOST_PHY_DATA_REG 0x304
> +
> +/* eMMC5.1 PHY Specific Registers */
> +#define DLL_CONTROL_STS 0x00
> +#define IOPAD_CONTROL1 0x01
> +#define IOPAD_CONTROL2 0x02
> +#define IOPAD_STATUS 0x03
> +#define IO_ODEN_CONTROL1 0x04
> +#define IO_ODEN_CONTROL2 0x05
> +#define IO_REN_CONTROL1 0x06
> +#define IO_REN_CONTROL2 0x07
> +#define IO_PU_CONTROL1 0x08
> +#define IO_PU_CONTROL2 0x09
> +#define IO_OD_REL_CONTROL1 0x0A
> +#define IO_OD_REL_CONTROL2 0x0B
> +#define ITAP_DELAY 0x0C
> +#define OTAP_DELAY 0x0D
> +#define STROBE_SELECT 0x0E
> +#define CLKBUF_SELECT 0x0F
> +#define MODE_CONTROL 0x11
> +#define DLL_TRIM 0x12
> +#define LDO_CONTROL 0x1F
> +#define CMD_CONTROL 0x20
> +#define DATA_CONTROL 0x21
> +#define STROBE_CONTROL 0x22
> +#define CLK_CONTROL 0x23
> +#define PHY_CONTROL 0x24
> +
> +#define DLL_ENABLE BIT(3)
> +#define RTRIM_ENABLE BIT(1)
> +#define PDB_ENABLE BIT(1)
> +#define RETB_ENABLE 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 ITAP_DLY_EN BIT(0)
> +#define OTAP_DLY_EN BIT(0)
> +#define OD_REL_CMD BIT(1)
> +#define OD_REL_DAT 0xFF
> +#define DLL_TRIM_ICP 0x8
> +#define PDB_CMD BIT(0)
> +#define PDB_DAT 0xFF
> +#define PDB_STRB BIT(0)
> +#define PDB_CLK BIT(0)
> +#define LDO_RDYB 0xFE
> +#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)
> +
> +#define OTAPDLY(x) ((x << 1) | OTAP_DLY_EN)
> +#define ITAPDLY(x) ((x << 1) | ITAP_DLY_EN)
> +#define FREQ_SEL(x) ((x << 5) | DLL_ENABLE)
> +#define IOPAD(x, y) ((x) | (y << 2))

Please make all the defines line up.

> +
> +

Please do not have double blank lines.

> +static int arasan_phy_write(struct sdhci_host *host, u8 data, u8 offset)
> +{
> + u32 timeout;
> + u8 busy;
> +
> + sdhci_writew(host, data, HOST_PHY_DATA_REG);
> + sdhci_writew(host, ((1<<8) | offset), HOST_PHY_ADDR_REG);

Why no define for (1 << 8)?

> + timeout = 20;
> + do {
> + busy = sdhci_readw(host, HOST_PHY_ADDR_REG) & (1<<9);

Why no define for (1 << 9)?

> + if (!busy)
> + break;
> + usleep_range(1, 5);
> + } while (timeout--);
> + if (!timeout)
> + return -EBUSY;
> + return 0;
> +}
> +
> +static int arasan_phy_read(struct sdhci_host *host, u8 offset, u8 *data)
> +{
> + u32 timeout;
> + u8 busy;
> +
> + sdhci_writew(host, 0, HOST_PHY_DATA_REG);
> + sdhci_writew(host, offset, HOST_PHY_ADDR_REG);
> + timeout = 20;
> + do {
> + busy = sdhci_readw(host, HOST_PHY_ADDR_REG) & (1<<9);
> + if (!busy)
> + break;
> + usleep_range(1, 5);
> + } while (timeout--);
> + if (!timeout)
> + return -EBUSY;

This timeout code is exactly the same as in arasan_phy_write(). Maybe
make it a separate function.

> + /*Masking valid data bits*/

Comment is nicer if there is a space after /* and before */

> + *data = sdhci_readw(host, HOST_PHY_DATA_REG) & 0xFF;
> + return 0;
> +}
> +
> +/* Initialize the Arasan PHY */
> +static int arasan_phy_init(struct sdhci_host *host)
> +{
> + struct sdhci_pci_slot *slot = sdhci_priv(host);
> + struct pci_dev *pdev = slot->chip->pdev;
> + u32 timeout;
> + u8 val, ret;

According to arasan_phy_read(), 'ret' needs to be an 'int'.

> +
> + /* Program IOPADs and wait for calibration to be done */
> + if (arasan_phy_read(host, IOPAD_CONTROL1, &val) ||
> + arasan_phy_write(host, val | RETB_ENABLE | PDB_ENABLE,
> + IOPAD_CONTROL1) ||
> + arasan_phy_read(host, IOPAD_CONTROL2, &val) ||
> + arasan_phy_write(host, val | RTRIM_ENABLE, IOPAD_CONTROL2))

It would be better to align to open parenthessis. Try checkpatch.pl --strict

> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, IOPAD_STATUS, &val);
> + if (val & CALDONE_MASK)
> + break;
> + usleep_range(1, 5);
> + } while (timeout--);

You have a lot of these timeouts. Please try to make a function.
Here is an example:

static int arasan_phy_poll(struct sdhci_host *host, u8 offset, u8 mask)
{
ktime_t timeout = ktime_add_us(ktime_get(), 100);
bool failed;
u8 val = 0;

while (1) {
failed = ktime_after(ktime_get(), timeout);
arasan_phy_read(host, offset, &val);
if (val & mask)
return 0;
if (failed)
return -EBUSY;
}
}


> + if (!timeout) {
> + dev_err(&pdev->dev, "Phy Calibration not done\n");
> + return ret;
> + }
> +
> + /* Program CMD/Data lines */
> + if (arasan_phy_read(host, IO_REN_CONTROL1, &val) ||
> + arasan_phy_write(host, val | REN_CMD | REN_STRB,
> + IO_REN_CONTROL1) ||
> + arasan_phy_read(host, IO_PU_CONTROL1, &val) ||
> + arasan_phy_write(host, val | PU_CMD, IO_PU_CONTROL1) ||
> + arasan_phy_read(host, CMD_CONTROL, &val) ||
> + arasan_phy_write(host, val | PDB_CMD, CMD_CONTROL) ||
> + arasan_phy_read(host, IO_REN_CONTROL2, &val) ||
> + arasan_phy_write(host, val | REN_DAT, IO_REN_CONTROL2) ||
> + arasan_phy_read(host, IO_PU_CONTROL2, &val) ||
> + arasan_phy_write(host, val | PU_DAT, IO_PU_CONTROL2) ||
> + arasan_phy_read(host, DATA_CONTROL, &val) ||
> + arasan_phy_write(host, val | PDB_DAT, DATA_CONTROL) ||
> + arasan_phy_read(host, STROBE_CONTROL, &val) ||
> + arasan_phy_write(host, val | PDB_STRB, STROBE_CONTROL) ||
> + arasan_phy_read(host, CLK_CONTROL, &val) ||
> + arasan_phy_write(host, val | PDB_CLK, CLK_CONTROL) ||
> + arasan_phy_read(host, CLKBUF_SELECT, &val) ||
> + arasan_phy_write(host, val | MAX_CLK_BUF, CLKBUF_SELECT) ||
> + arasan_phy_write(host, LEGACY_MODE, MODE_CONTROL))
> + return -EBUSY;
> + return 0;
> +}
> +
> +static int arasan_set_phy(struct sdhci_host *host)
> +{
> + u8 freq_sel;
> + static u32 chg_clk;

Please put chg_clk in private data - refer:
commit ac9f67b5800b9a96987ec602a34dd256a92ac7ca
mmc: sdhci-pci: Let devices define their own private data

> + u32 timeout;
> + u8 val, ret;
> +
> + if (chg_clk == host->mmc->ios.clock)
> + return 0;
> +
> + chg_clk = host->mmc->ios.clock;
> + if (host->mmc->ios.clock == 200000000)
> + freq_sel = 0x0;
> + else if (host->mmc->ios.clock == 100000000)
> + freq_sel = 0x2;
> + else if (host->mmc->ios.clock == 50000000)
> + freq_sel = 0x1;
> + else
> + freq_sel = 0x0;
> +
> + if (host->mmc_host_ops.hs400_enhanced_strobe) {
> + if (arasan_phy_write(host, 0x1, MODE_CONTROL) ||
> + arasan_phy_write(host, OTAPDLY(1), OTAP_DELAY) ||
> + arasan_phy_write(host, 0, ITAP_DELAY) ||
> + arasan_phy_write(host, DLL_TRIM_ICP, DLL_TRIM) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS) ||
> + arasan_phy_write(host, FREQ_SEL(freq_sel),
> + DLL_CONTROL_STS))
> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, DLL_CONTROL_STS, &val);
> + if (val & DLL_RDY_MASK)
> + break;
> + } while (timeout--);
> + if (!timeout) {
> + dev_err(&pdev->dev, "DLL status not set\n");

drivers/mmc/host/sdhci-pci-arasan.c: In function âarasan_set_phyâ:
drivers/mmc/host/sdhci-pci-arasan.c:218:13: error: âpdevâ undeclared (first use in this function)
dev_err(&pdev->dev, "DLL status not set\n");
^

> + return -EBUSY;
> + }
> + } else {
> + switch (host->mmc->ios.timing) {
> + case MMC_TIMING_LEGACY:
> + if (arasan_phy_write(host, 0x4, MODE_CONTROL) ||
> + arasan_phy_write(host, 0, ITAP_DELAY) ||
> + arasan_phy_write(host, 0, OTAP_DELAY) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS))
> + return -EBUSY;
> + break;
> + case MMC_TIMING_MMC_HS:
> + case MMC_TIMING_SD_HS:
> + if (arasan_phy_write(host, 0, MODE_CONTROL) ||
> + arasan_phy_write(host, OTAPDLY(3),
> + OTAP_DELAY) ||
> + arasan_phy_write(host, ITAPDLY(0x2),
> + ITAP_DELAY) ||
> + arasan_phy_write(host, 0, ITAP_DELAY) ||
> + arasan_phy_write(host, DLL_TRIM_ICP,
> + DLL_TRIM) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS) ||
> + arasan_phy_write(host, FREQ_SEL(freq_sel),
> + DLL_CONTROL_STS))
> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, DLL_CONTROL_STS,
> + &val);
> + if (val & DLL_RDY_MASK)
> + break;
> + } while (timeout--);
> + if (!timeout) {
> + dev_err(&pdev->dev, "DLL status not set\n");
> + return -EBUSY;
> + }
> + break;
> + case MMC_TIMING_MMC_HS200:
> + case MMC_TIMING_UHS_SDR104:
> + if (arasan_phy_write(host, 0, MODE_CONTROL) ||
> + arasan_phy_read(host, IOPAD_CONTROL1, &val) ||
> + arasan_phy_write(host, IOPAD(val,
> + host->mmc->ios.drv_type),
> + IOPAD_CONTROL1) ||

Please restructure to avoid wrapping lines.

> + arasan_phy_write(host, OTAPDLY(1),
> + OTAP_DELAY) ||
> + arasan_phy_write(host, 0, ITAP_DELAY) ||
> + arasan_phy_write(host, DLL_TRIM_ICP,
> + DLL_TRIM) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS) ||
> + arasan_phy_write(host, FREQ_SEL(freq_sel),
> + DLL_CONTROL_STS))
> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, DLL_CONTROL_STS,
> + &val);
> + if (val & DLL_RDY_MASK)
> + break;
> + } while (timeout--);
> + if (!timeout) {
> + dev_err(&pdev->dev, "DLL status not set\n");
> + return -EBUSY;
> + }
> + break;
> + case MMC_TIMING_MMC_DDR52:
> + case MMC_TIMING_UHS_DDR50:
> + if (arasan_phy_write(host, 0x8, MODE_CONTROL) ||
> + arasan_phy_write(host, OTAPDLY(3),
> + OTAP_DELAY) ||
> + arasan_phy_write(host, ITAPDLY(0x2),
> + ITAP_DELAY) ||
> + arasan_phy_write(host, DLL_TRIM_ICP,
> + DLL_TRIM) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS) ||
> + arasan_phy_write(host, FREQ_SEL(freq_sel),
> + DLL_CONTROL_STS))
> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, DLL_CONTROL_STS,
> + &val);
> + if (val & DLL_RDY_MASK)
> + break;
> + } while (timeout--);
> + if (!timeout) {
> + dev_err(&pdev->dev, "DLL status not set\n");
> + return -EBUSY;
> + }
> + break;
> + case MMC_TIMING_MMC_HS400:
> + if (arasan_phy_write(host, 0x2, MODE_CONTROL) ||
> + arasan_phy_read(host, IOPAD_CONTROL1, &val) ||
> + arasan_phy_write(host, IOPAD(val,
> + host->mmc->ios.drv_type),
> + IOPAD_CONTROL1) ||
> + arasan_phy_write(host, OTAPDLY(1),
> + OTAP_DELAY) ||
> + arasan_phy_write(host, ITAPDLY(0xa),
> + ITAP_DELAY) ||
> + arasan_phy_write(host, DLL_TRIM_ICP,
> + DLL_TRIM) ||
> + arasan_phy_write(host, 0, DLL_CONTROL_STS) ||
> + arasan_phy_write(host, FREQ_SEL(freq_sel),
> + DLL_CONTROL_STS))
> + return -EBUSY;
> + timeout = 10;
> + do {
> + ret = arasan_phy_read(host, DLL_CONTROL_STS,
> + &val);
> + if (val & DLL_RDY_MASK)
> + break;
> + } while (timeout--);
> + if (!timeout) {
> + dev_err(&pdev->dev, "DLL status not set\n");
> + return -EBUSY;
> + }
> + break;
> + default:
> + break;
> + }
> + }
> + return 0;
> +}
> +
> +int arasan_pci_probe_slot(struct sdhci_pci_slot *slot)
> +{
> + int err;
> +
> + slot->host->mmc->caps |= MMC_CAP_NONREMOVABLE |
> + MMC_CAP_8_BIT_DATA;

unnecessary line wrap.

> + err = arasan_phy_init(slot->host);
> + if (err)
> + return -ENODEV;
> + return 0;
> +}
> +
> +void arasan_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> + u16 clk;
> +
> + host->mmc->actual_clock = 0;
> + sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> + if (clock == 0)
> + return;
> + clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
> + sdhci_enable_clk(host, clk);

That is the same as sdhci_set_clock(). Please call sdhci_set_clock() instead.

> +
> + /*Change phy settings for the new clock */

Please add space after /*

> + arasan_set_phy(host);
> +}
> diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
> index 3e4f04f..cb89161 100644
> --- a/drivers/mmc/host/sdhci-pci-core.c
> +++ b/drivers/mmc/host/sdhci-pci-core.c
> @@ -1104,6 +1104,19 @@ static const struct sdhci_pci_fixes sdhci_rtsx = {
> .probe_slot = rtsx_probe_slot,
> };
>
> +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,
> +};
> +
> +static const struct sdhci_pci_fixes sdhci_arasan = {
> + .probe_slot = arasan_pci_probe_slot,
> + .ops = &arasan_sdhci_pci_ops,
> +};
> +
> /*AMD chipset generation*/
> enum amd_chipset_gen {
> AMD_CHIPSET_BEFORE_ML,
> @@ -1306,6 +1319,7 @@ 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)},
> diff --git a/drivers/mmc/host/sdhci-pci.h b/drivers/mmc/host/sdhci-pci.h
> index 063506c..63cdab5 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
> +
> /*
> * PCI device class and mask
> */
> @@ -176,4 +179,7 @@ int sdhci_pci_o2_probe(struct sdhci_pci_chip *chip);
> int sdhci_pci_o2_resume(struct sdhci_pci_chip *chip);
> #endif
>
> +int arasan_pci_probe_slot(struct sdhci_pci_slot *slot);
> +void arasan_sdhci_set_clock(struct sdhci_host *host, unsigned int clock);
> +
> #endif /* __SDHCI_PCI_H */
>