[RESEND PATCH v6 2/2] mmc: openpiton: add piton_mmc driver
Tianrui Wei
tianrui-wei at outlook.com
Mon Jun 14 02:28:08 CEST 2021
Hi Jaehoon,
Many thanks for taking the time to review our patches :P
On 6/14/2021 6:09 AM, Jaehoon Chung wrote:
> Dear Tianrui,
>
> On 6/13/21 2:16 AM, Tianrui Wei wrote:
>> This commit adds support to piton_mmc driver for OpenPiton-riscv64
>> In particular, this driver
>>
>> - V6
>> . change type of address
>> . move declarations ahead
>> . loop style update
>>
>> Signed-off-by: Tianrui Wei <tianrui-wei at outlook.com>
>> Signed-off-by: Jonathan Balkind <jbalkind at ucsb.edu>
>> ---
>> drivers/mmc/Kconfig | 9 +++
>> drivers/mmc/Makefile | 1 +
>> drivers/mmc/piton_mmc.c | 169 ++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 179 insertions(+)
>> create mode 100644 drivers/mmc/piton_mmc.c
>>
>> diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
>> index 8901456967..096d6a930c 100644
>> --- a/drivers/mmc/Kconfig
>> +++ b/drivers/mmc/Kconfig
>> @@ -727,6 +727,15 @@ config MMC_SUNXI_HAS_MODE_SWITCH
>> bool
>> depends on MMC_SUNXI
>>
>> +config MMC_PITON
>> + bool "MMC support for OpenPiton SoC"
>> + depends on DM_MMC && BLK
>> + help
>> + This selects support for the SD host controller on
>> + OpenPiton SoC. Note that this SD controller directly
>> + exposes the contents of the SD card as memory mapped,
>> + so there is no manual configuration required
> Fix indentation.
Will do
>
>> +
>> config GENERIC_ATMEL_MCI
>> bool "Atmel Multimedia Card Interface support"
>> depends on DM_MMC && BLK && ARCH_AT91
>> diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
>> index 89d6af3db3..cc08b41d0d 100644
>> --- a/drivers/mmc/Makefile
>> +++ b/drivers/mmc/Makefile
>> @@ -72,6 +72,7 @@ obj-$(CONFIG_MMC_SDHCI_XENON) += xenon_sdhci.o
>> obj-$(CONFIG_MMC_SDHCI_ZYNQ) += zynq_sdhci.o
>>
>> obj-$(CONFIG_MMC_SUNXI) += sunxi_mmc.o
>> +obj-$(CONFIG_MMC_PITON) += piton_mmc.o
> Ditto.
>
>> obj-$(CONFIG_MMC_UNIPHIER) += tmio-common.o uniphier-sd.o
>> obj-$(CONFIG_RENESAS_SDHI) += tmio-common.o renesas-sdhi.o
>> obj-$(CONFIG_MMC_BCM2835) += bcm2835_sdhost.o
>> diff --git a/drivers/mmc/piton_mmc.c b/drivers/mmc/piton_mmc.c
>> new file mode 100644
>> index 0000000000..32671d1a89
>> --- /dev/null
>> +++ b/drivers/mmc/piton_mmc.c
>> @@ -0,0 +1,169 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * (C) Copyright 2009 SAMSUNG Electronics
>> + * Minkyu Kang <mk7.kang at samsung.com>
>> + * Jaehoon Chung <jh80.chung at samsung.com>
>> + * Portions Copyright 2011-2019 NVIDIA Corporation
>> + * Portions Copyright 2021 Tianrui Wei
>> + * This file is adapted from tegra_mmc.c
>> + * Tianrui Wei <tianrui-wei at outlook.com>
>> + */
>> +
>> +#include <asm/gpio.h>
>> +#include <asm/io.h>
>> +#include <common.h>
>> +#include <div64.h>
>> +#include <dm.h>
>> +#include <errno.h>
>> +#include <linux/bitops.h>
>> +#include <linux/delay.h>
>> +#include <linux/err.h>
>> +#include <linux/types.h>
>> +#include <log.h>
>> +#include <mmc.h>
>> +
>> +struct piton_mmc_plat {
>> + struct mmc_config cfg;
>> + struct mmc mmc;
>> +};
>> +
>> +struct piton_mmc_priv {
>> + void __iomem *piton_mmc_base_addr; /* peripheral id */
>> +};
>> +
>> +/*
>> + * see mmc_read_blocks to see how it is used.
>> + * start block is hidden at cmd->arg
>> + * also, initialize the block size at init
>> + */
>> +static int piton_mmc_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
>> + struct mmc_data *data)
> Ditto.
Will do
>
>> +{
>> + /* check first if this is a pure command */
>> + if (!data)
>> + return 0;
>> +
>> + struct piton_mmc_priv *priv = dev_get_priv(dev);
>> + u32 *buff, *start_addr;
>> + size_t byte_cnt, start_block;
>> +
>> + buff = (u32 *)data->dest;
>> + start_block = cmd->cmdarg;
>> + start_addr = priv->piton_mmc_base_addr + start_block;
>> +
>> + /* if there is a read */
>> + if (data->flags & MMC_DATA_READ) {
>> + for (byte_cnt = data->blocks * data->blocksize; byte_cnt;
>> + byte_cnt -= sizeof(u32)) {
>> + *buff++ = readl(start_addr++);
>> + }
>> + } else {
>> + return -ENOSYS;
> Is is right to return -ENOSYS? MMC_DATA_WRITE doesn't support?
Will change to support it
>
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int piton_mmc_ofdata_to_platdata(struct udevice *dev)
>> +{
>> + struct piton_mmc_priv *priv = dev_get_priv(dev);
>> + struct piton_mmc_plat *plat = dev_get_platdata(dev);
>> + struct mmc_config *cfg;
>> + struct mmc *mmc;
>> + /* fill in device description */
>> + struct blk_desc *bdesc;
>> +
>> + priv->piton_mmc_base_addr = (void *)dev_read_addr(dev);
>> + cfg = &plat->cfg;
>> + cfg->name = "PITON MMC";
>> + cfg->host_caps = MMC_MODE_8BIT;
>> + cfg->f_max = 100000;
> f_max is 100K? I don't think so.
We don't use f_max anywhere, so we're setting dummy values :P
>
>> + cfg->f_min = 400000;
>> + cfg->voltages = MMC_VDD_21_22;
>> +
>> + mmc = &plat->mmc;
>> + mmc->read_bl_len = MMC_MAX_BLOCK_LEN;
>> + mmc->capacity_user = 0x100000000;
>> + mmc->capacity_user *= mmc->read_bl_len;
>> + mmc->capacity_boot = 0;
>> + mmc->capacity_rpmb = 0;
>> + for (int i = 0; i < 4; i++)
>> + mmc->capacity_gp[i] = 0;
>> + mmc->capacity = 0x2000000000ULL;
> Use macro. It's not readable. What's 0x2000000000ULL?
Will do
>
>> + mmc->has_init = 1;
> Right? has_init will be set in mmc.c.
> Why it's set to 1 in driver?
Our mmc controller directly maps the contents of the SD card into a
memory region, so there're no configuration registers avaiable. We're
setting these values to avoid problems with mmc.c
>
>> +
>> + bdesc = mmc_get_blk_desc(mmc);
>> + bdesc->lun = 0;
>> + bdesc->hwpart = 0;
>> + bdesc->type = 0;
>> + bdesc->blksz = mmc->read_bl_len;
>> + bdesc->log2blksz = LOG2(bdesc->blksz);
>> + bdesc->lba = lldiv(mmc->capacity, mmc->read_bl_len);
>> +
>> + return 0;
>> +}
>> +
>> +/* test if the micro sd card is present
>> + * always return 1, which means present
>> + */
>> +static int piton_mmc_getcd(struct udevice *dev)
>> +{
>> + /*
>> + * always return 1
>> + */
>> + return 1;
>> +}
>> +
>> +/* dummy function, piton_mmc don't need initialization
>> + * in hw
>> + */
>> +static const struct dm_mmc_ops piton_mmc_ops = {
>> + .send_cmd = piton_mmc_send_cmd,
>> + .get_cd = piton_mmc_getcd,
>> +};
>> +
>> +static int piton_mmc_probe(struct udevice *dev)
>> +{
>> + struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
>> + struct piton_mmc_plat *plat = dev_get_platdata(dev);
>> + struct mmc_config *cfg = &plat->cfg;
>> +
>> + cfg->name = dev->name;
>> + upriv->mmc = &plat->mmc;
>> + upriv->mmc->has_init = 1;
> Ditto.
Ditto
>
>> + upriv->mmc->capacity = 0x2000000000ULL;
> Ditto.
Ditto
>
>> + upriv->mmc->read_bl_len = MMC_MAX_BLOCK_LEN;
> readl_blk_len will be set in mmc.c.
> Your driver doesn't use mmc.c? Why do you set to some values in your driver?
Ditto
>
>> + return 0;
>> +}
>> +
>> +static int piton_mmc_bind(struct udevice *dev)
>> +{
>> + struct piton_mmc_plat *plat = dev_get_platdata(dev);
>> + struct mmc_config *cfg = &plat->cfg;
>> +
>> + cfg->name = dev->name;
>> + cfg->host_caps = MMC_MODE_HS_52MHz | MMC_MODE_HS | MMC_MODE_8BIT;
>> + cfg->voltages = MMC_VDD_165_195 | MMC_VDD_32_33 | MMC_VDD_33_34;
>> + cfg->f_min = 1000000;
>> + cfg->f_max = 52000000;
>> + cfg->b_max = U32_MAX;
> Use a readable value instead of U32_MAX. CONFIG_SYS_MMC_MAX_BLK_COUNT or other.
Will do.
Thanks for your review and helpful comments. We're very keen to get this
upstream so I
will address your issues ASAP and get a new version submitted. Regarding
readl_blk_len,
our MMC is a bit of a special case in that it's directly memory mapped
under the hood.
Can we go ahead with this version or might you have another suggestion?
Best regards,
Tianrui
>
> Best Regards,
> Jaehoon Chung
>
>> +
>> + return mmc_bind(dev, &plat->mmc, cfg);
>> +}
>> +
>> +static const struct udevice_id piton_mmc_ids[] = {
>> + {.compatible = "openpiton,piton-mmc"},
>> + {/* sentinel */}
>> +};
>> +
>> +U_BOOT_DRIVER(piton_mmc_drv) = {
>> + .name = "piton_mmc",
>> + .id = UCLASS_MMC,
>> + .of_match = piton_mmc_ids,
>> + .ofdata_to_platdata = piton_mmc_ofdata_to_platdata,
>> + .bind = piton_mmc_bind,
>> + .probe = piton_mmc_probe,
>> + .ops = &piton_mmc_ops,
>> + .platdata_auto_alloc_size = sizeof(struct piton_mmc_plat),
>> + .priv_auto_alloc_size = sizeof(struct piton_mmc_priv),
>> +};
>>
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