On Fri, Dec 03, 2021 at 06:41:55PM -0500, Gabriel Somlo wrote: > LiteX (https://github.com/enjoy-digital/litex) is a SoC framework > that targets FPGAs. LiteSDCard is a small footprint, configurable > SDCard core commonly used in LiteX designs. > > The driver was first written in May 2020 and has been maintained > cooperatively by the LiteX community. Thanks to all contributors! > > Co-developed-by: Kamil Rakoczy <krakoczy@xxxxxxxxxxxx> > Signed-off-by: Kamil Rakoczy <krakoczy@xxxxxxxxxxxx> > Co-developed-by: Maciej Dudek <mdudek@xxxxxxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Maciej Dudek <mdudek@xxxxxxxxxxxxxxxxxxxxxxxx> > Co-developed-by: Paul Mackerras <paulus@xxxxxxxxxx> > Signed-off-by: Paul Mackerras <paulus@xxxxxxxxxx> > Signed-off-by: Gabriel Somlo <gsomlo@xxxxxxxxx> > Cc: Mateusz Holenko <mholenko@xxxxxxxxxxxx> > Cc: Karol Gugala <kgugala@xxxxxxxxxxxx> > Cc: Joel Stanley <joel@xxxxxxxxx> > Cc: Stafford Horne <shorne@xxxxxxxxx> > Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > Cc: David Abdurachmanov <david.abdurachmanov@xxxxxxxxxx> > Cc: Florent Kermarrec <florent@xxxxxxxxxxxxxxxx> > --- > drivers/mmc/host/Kconfig | 6 + > drivers/mmc/host/Makefile | 1 + > drivers/mmc/host/litex_mmc.c | 677 +++++++++++++++++++++++++++++++++++ > 3 files changed, 684 insertions(+) > create mode 100644 drivers/mmc/host/litex_mmc.c > > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > index 5af8494c31b5..84c64e72195d 100644 > --- a/drivers/mmc/host/Kconfig > +++ b/drivers/mmc/host/Kconfig > @@ -1093,3 +1093,9 @@ config MMC_OWL > > config MMC_SDHCI_EXTERNAL_DMA > bool > + > +config MMC_LITEX > + tristate "Support for the MMC Controller in LiteX SOCs" > + depends on OF && LITEX Shall we allow compile test here like this? depends on OF || COMPILE_TEST depends on LITEX || COMPILE_TEST This is what was added for liteuart [0]. [0] https://lore.kernel.org/all/CAHp75Ve9MB4MW9KDPoNhnPa8TCabmMgLbt6H7qrGgwmA8CpdNg@xxxxxxxxxxxxxx/T/#mad93ad951031f8e975a1c632873f516598aec272 > + help > + Generic MCC driver for LiteX > diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile > index ea36d379bd3c..4e4ceb32c4b4 100644 > --- a/drivers/mmc/host/Makefile > +++ b/drivers/mmc/host/Makefile > @@ -101,6 +101,7 @@ obj-$(CONFIG_MMC_CQHCI) += cqhci.o > cqhci-y += cqhci-core.o > cqhci-$(CONFIG_MMC_CRYPTO) += cqhci-crypto.o > obj-$(CONFIG_MMC_HSQ) += mmc_hsq.o > +obj-$(CONFIG_MMC_LITEX) += litex_mmc.o > > ifeq ($(CONFIG_CB710_DEBUG),y) > CFLAGS-cb710-mmc += -DDEBUG > diff --git a/drivers/mmc/host/litex_mmc.c b/drivers/mmc/host/litex_mmc.c > new file mode 100644 > index 000000000000..3877379757cd > --- /dev/null > +++ b/drivers/mmc/host/litex_mmc.c > @@ -0,0 +1,677 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * LiteX LiteSDCard driver > + * > + * Copyright (C) 2019-2020 Antmicro <www.antmicro.com> > + * > + */ > + > +#include <linux/module.h> > +#include <linux/litex.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/mmc/sd.h> > +#include <linux/mmc/mmc.h> > +#include <linux/mmc/host.h> > +#include <linux/mmc/slot-gpio.h> > +#include <linux/delay.h> > +#include <linux/dma-mapping.h> > + > +#define LITEX_PHY_CARDDETECT 0x00 > +#define LITEX_PHY_CLOCKERDIV 0x04 > +#define LITEX_PHY_INITIALIZE 0x08 > +#define LITEX_PHY_WRITESTATUS 0x0C > +#define LITEX_CORE_CMDARG 0x00 > +#define LITEX_CORE_CMDCMD 0x04 > +#define LITEX_CORE_CMDSND 0x08 > +#define LITEX_CORE_CMDRSP 0x0C > +#define LITEX_CORE_CMDEVT 0x1C > +#define LITEX_CORE_DATAEVT 0x20 > +#define LITEX_CORE_BLKLEN 0x24 > +#define LITEX_CORE_BLKCNT 0x28 > +#define LITEX_BLK2MEM_BASE 0x00 > +#define LITEX_BLK2MEM_LEN 0x08 > +#define LITEX_BLK2MEM_ENA 0x0C > +#define LITEX_BLK2MEM_DONE 0x10 > +#define LITEX_BLK2MEM_LOOP 0x14 > +#define LITEX_MEM2BLK_BASE 0x00 > +#define LITEX_MEM2BLK_LEN 0x08 > +#define LITEX_MEM2BLK_ENA 0x0C > +#define LITEX_MEM2BLK_DONE 0x10 > +#define LITEX_MEM2BLK_LOOP 0x14 > +#define LITEX_MEM2BLK 0x18 > +#define LITEX_IRQ_STATUS 0x00 > +#define LITEX_IRQ_PENDING 0x04 > +#define LITEX_IRQ_ENABLE 0x08 > + > +#define SDCARD_CTRL_DATA_TRANSFER_NONE 0 > +#define SDCARD_CTRL_DATA_TRANSFER_READ 1 > +#define SDCARD_CTRL_DATA_TRANSFER_WRITE 2 > + > +#define SDCARD_CTRL_RESPONSE_NONE 0 > +#define SDCARD_CTRL_RESPONSE_SHORT 1 > +#define SDCARD_CTRL_RESPONSE_LONG 2 > +#define SDCARD_CTRL_RESPONSE_SHORT_BUSY 3 > + > +#define SD_OK 0 > +#define SD_WRITEERROR 1 > +#define SD_TIMEOUT 2 > +#define SD_CRCERROR 3 > +#define SD_ERR_OTHER 4 > + > +#define SDIRQ_CARD_DETECT 1 > +#define SDIRQ_SD_TO_MEM_DONE 2 > +#define SDIRQ_MEM_TO_SD_DONE 4 > +#define SDIRQ_CMD_DONE 8 > + > +struct litex_mmc_host { > + struct mmc_host *mmc; > + struct platform_device *dev; > + > + void __iomem *sdphy; > + void __iomem *sdcore; > + void __iomem *sdreader; > + void __iomem *sdwriter; > + void __iomem *sdirq; > + > + u32 resp[4]; > + u16 rca; > + > + void *buffer; > + size_t buf_size; > + dma_addr_t dma; > + > + unsigned int freq; > + unsigned int clock; > + bool is_bus_width_set; > + bool app_cmd; > + > + int irq; > + struct completion cmd_done; > +}; > + > +static int > +sdcard_wait_done(void __iomem *reg) > +{ > + u8 evt; > + > + for (;;) { > + evt = litex_read8(reg); > + if (evt & 0x1) > + break; > + udelay(5); > + } Should we replace this with something like read_poll_timeout? if (read_poll_timeout(litex_read8, evt, (evt & 0x1), 5, 20000, false, reg)) { pr_err ("read timeout ...."); return SD_TIMEOUT; } Otherwise we could be locked here forever. > + if (evt == 0x1) > + return SD_OK; > + if (evt & 0x2) > + return SD_WRITEERROR; > + if (evt & 0x4) > + return SD_TIMEOUT; > + if (evt & 0x8) > + return SD_CRCERROR; > + pr_err("%s: unknown error evt=%x\n", __func__, evt); > + return SD_ERR_OTHER; > +} > + > +static int > +send_cmd(struct litex_mmc_host *host, > + u8 cmd, u32 arg, u8 response_len, u8 transfer) > +{ > + void __iomem *reg; > + ulong n; > + u8 i; > + int status; > + > + litex_write32(host->sdcore + LITEX_CORE_CMDARG, arg); > + litex_write32(host->sdcore + LITEX_CORE_CMDCMD, > + cmd << 8 | transfer << 5 | response_len); > + litex_write8(host->sdcore + LITEX_CORE_CMDSND, 1); > + > + /* Wait for an interrupt if we have an interrupt and either there is > + * data to be transferred, or if the card can report busy via DAT0. > + */ > + if (host->irq > 0 && > + (transfer != SDCARD_CTRL_DATA_TRANSFER_NONE || > + response_len == SDCARD_CTRL_RESPONSE_SHORT_BUSY)) { > + reinit_completion(&host->cmd_done); > + litex_write32(host->sdirq + LITEX_IRQ_ENABLE, > + SDIRQ_CMD_DONE | SDIRQ_CARD_DETECT); > + wait_for_completion(&host->cmd_done); > + } > + > + status = sdcard_wait_done(host->sdcore + LITEX_CORE_CMDEVT); > + > + if (status != SD_OK) { > + pr_err("Command (cmd %d) failed, status %d\n", cmd, status); > + return status; > + } > + > + if (response_len != SDCARD_CTRL_RESPONSE_NONE) { > + reg = host->sdcore + LITEX_CORE_CMDRSP; > + for (i = 0; i < 4; i++) { > + host->resp[i] = litex_read32(reg); > + reg += sizeof(u32); > + } > + } > + > + if (!host->app_cmd && cmd == SD_SEND_RELATIVE_ADDR) > + host->rca = (host->resp[3] >> 16) & 0xffff; > + > + host->app_cmd = (cmd == MMC_APP_CMD); > + > + if (transfer == SDCARD_CTRL_DATA_TRANSFER_NONE) > + return status; /* SD_OK from prior sdcard_wait_done(cmd_evt) */ > + > + status = sdcard_wait_done(host->sdcore + LITEX_CORE_DATAEVT); > + if (status != SD_OK) { > + pr_err("Data xfer (cmd %d) failed, status %d\n", cmd, status); > + return status; > + } > + > + /* wait for completion of (read or write) DMA transfer */ > + reg = (transfer == SDCARD_CTRL_DATA_TRANSFER_READ) ? > + host->sdreader + LITEX_BLK2MEM_DONE : > + host->sdwriter + LITEX_MEM2BLK_DONE; > + n = jiffies + (HZ << 1); > + while ((litex_read8(reg) & 0x01) == 0) > + if (time_after(jiffies, n)) { > + pr_err("DMA timeout (cmd %d)\n", cmd); > + return SD_TIMEOUT; > + } We could use read_poll_timeout here too. > + > + return status; > +} > + -Stafford
