QEMU can expose eMMC through the class-compliant sdhci-pci device, but barebox only had platform SDHCI glue. Add a PCI host driver that maps BAR0, enables bus mastering, initializes the SDHCI core and registers an MCI host.
Assisted-by: Codex:gpt-5.5 Signed-off-by: Ahmad Fatoum <[email protected]> --- v2 -> v3: - drop erroneous commit message passage explaining lack of DMA support. (Sascha) v1 -> v2: - new commit --- drivers/mci/Kconfig | 8 ++ drivers/mci/Makefile | 1 + drivers/mci/sdhci-pci.c | 203 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 212 insertions(+) create mode 100644 drivers/mci/sdhci-pci.c diff --git a/drivers/mci/Kconfig b/drivers/mci/Kconfig index b38f7a3bdf8b..55e63aad92d4 100644 --- a/drivers/mci/Kconfig +++ b/drivers/mci/Kconfig @@ -90,6 +90,14 @@ config MCI_MMC_RPMB comment "--- MCI host drivers ---" +config MCI_SDHCI_PCI + bool "PCI SDHCI controller" + depends on PCI && HAS_DMA + select MCI_SDHCI + help + Enable support for PCI-attached SDHCI controllers, such as QEMU's + sdhci-pci device used to attach emulated eMMC devices. + config MCI_DWC_MSHC bool "Synopsys DesignWare Cores MSHC" depends on HAS_DMA diff --git a/drivers/mci/Makefile b/drivers/mci/Makefile index 67a1f7bf1724..761f4187c079 100644 --- a/drivers/mci/Makefile +++ b/drivers/mci/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_MCI) += mci-core.o pbl-$(CONFIG_MCI) += mci-pbl.o obj-$(CONFIG_MCI_MMC_RPMB) += rpmb.o +obj-$(CONFIG_MCI_SDHCI_PCI) += sdhci-pci.o obj-$(CONFIG_MCI_AM654) += am654-sdhci.o obj-$(CONFIG_MCI_ARASAN) += arasan-sdhci.o obj-$(CONFIG_MCI_ATMEL) += atmel_mci.o atmel_mci_common.o diff --git a/drivers/mci/sdhci-pci.c b/drivers/mci/sdhci-pci.c new file mode 100644 index 000000000000..1c8ad5435697 --- /dev/null +++ b/drivers/mci/sdhci-pci.c @@ -0,0 +1,203 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <dma.h> +#include <init.h> +#include <io.h> +#include <malloc.h> +#include <mci.h> +#include <module.h> +#include <linux/pci.h> +#include <linux/pci_ids.h> + +#include "sdhci.h" + +struct sdhci_pci_host { + struct mci_host mci; + struct sdhci sdhci; +}; + +static inline struct sdhci_pci_host *to_sdhci_pci_host(struct mci_host *mci) +{ + return container_of(mci, struct sdhci_pci_host, mci); +} + +#define PCI_CLASS_SYSTEM_SDHCI_DMA ((PCI_CLASS_SYSTEM_SDHCI << 8) | 0x01) + +static const struct pci_device_id pci_ids[] = { + /* Generic SD host controller */ + {PCI_DEVICE_CLASS(PCI_CLASS_SYSTEM_SDHCI_DMA, PCI_ANY_ID)}, + { /* end: all zeroes */ }, +}; + +MODULE_DEVICE_TABLE(pci, pci_ids); + +/*****************************************************************************\ + * * + * MCI core callbacks * + * * +\*****************************************************************************/ + +static int sdhci_pci_init(struct mci_host *mci, struct device *dev) +{ + struct sdhci_pci_host *host = to_sdhci_pci_host(mci); + int ret; + + (void)dev; + + ret = sdhci_reset(&host->sdhci, SDHCI_RESET_ALL); + if (ret) + return ret; + + sdhci_write8(&host->sdhci, SDHCI_POWER_CONTROL, + SDHCI_BUS_VOLTAGE_330 | SDHCI_BUS_POWER_EN); + udelay(400); + + sdhci_write32(&host->sdhci, SDHCI_INT_ENABLE, + SDHCI_INT_CMD_MASK | SDHCI_INT_DATA_MASK); + sdhci_write32(&host->sdhci, SDHCI_SIGNAL_ENABLE, 0); + + return 0; +} + +static void sdhci_pci_set_ios(struct mci_host *mci, struct mci_ios *ios) +{ + struct sdhci_pci_host *host = to_sdhci_pci_host(mci); + u8 val; + + if (ios->clock) + sdhci_set_clock(&host->sdhci, ios->clock, host->sdhci.max_clk); + + sdhci_set_bus_width(&host->sdhci, ios->bus_width); + + val = sdhci_read8(&host->sdhci, SDHCI_HOST_CONTROL); + if (ios->clock > 26000000) + val |= SDHCI_CTRL_HISPD; + else + val &= ~SDHCI_CTRL_HISPD; + sdhci_write8(&host->sdhci, SDHCI_HOST_CONTROL, val); +} + +static int sdhci_pci_send_cmd(struct mci_host *mci, struct mci_cmd *cmd) +{ + struct sdhci_pci_host *host = to_sdhci_pci_host(mci); + + return sdhci_send_command(&host->sdhci, cmd); +} + +static int sdhci_pci_card_present(struct mci_host *mci) +{ + struct sdhci_pci_host *host = to_sdhci_pci_host(mci); + + return !!(sdhci_read32(&host->sdhci, SDHCI_PRESENT_STATE) & + SDHCI_CARD_PRESENT); +} + +static int sdhci_pci_card_write_protected(struct mci_host *mci) +{ + struct sdhci_pci_host *host = to_sdhci_pci_host(mci); + + return !(sdhci_read32(&host->sdhci, SDHCI_PRESENT_STATE) & + SDHCI_WRITE_PROTECT); +} + +static const struct mci_ops sdhci_pci_ops = { + .init = sdhci_pci_init, + .set_ios = sdhci_pci_set_ios, + .send_cmd = sdhci_pci_send_cmd, + .card_present = sdhci_pci_card_present, + .card_write_protected = sdhci_pci_card_write_protected, +}; + +/*****************************************************************************\ + * * + * Device probing/removal * + * * +\*****************************************************************************/ + +static int sdhci_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct sdhci_pci_host *host; + struct mci_host *mci; + void __iomem *base; + int ret; + + (void)ent; + + dev_info(&pdev->dev, "SDHCI controller found [%04x:%04x] (rev %x)\n", + (int)pdev->vendor, (int)pdev->device, (int)pdev->revision); + + ret = pci_enable_device(pdev); + if (ret) + return ret; + + pci_set_master(pdev); + + base = pci_iomap(pdev, 0); + if (!base) + return dev_err_probe(&pdev->dev, -EBUSY, "failed to map BAR0\n"); + + host = xzalloc(sizeof(*host)); + mci = &host->mci; + + host->sdhci.base = base; + host->sdhci.mci = mci; + host->sdhci.quirks2 = SDHCI_QUIRK2_BROKEN_HS200; + + mci->hw_dev = &pdev->dev; + mci->ops = sdhci_pci_ops; + mci->max_req_size = 0x8000; + + ret = sdhci_setup_host(&host->sdhci); + if (ret) + goto err; + + if (host->sdhci.flags & SDHCI_USE_64_BIT_DMA) + dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)); + else + dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); + + ret = sdhci_setup_adma(&host->sdhci); + if (ret && ret != -ENOTSUPP) + dev_warn(&pdev->dev, "ADMA setup failed (%pe), falling back to SDMA\n", + ERR_PTR(ret)); + + mci->f_max = host->sdhci.max_clk; + if (!mci->f_max) + mci->f_max = 50000000; + mci->f_min = mci->f_max / SDHCI_MAX_DIV_SPEC_300; + + pdev->dev.priv = host; + + ret = mci_register(mci); + if (ret) + goto err; + + return 0; + +err: + pdev->dev.priv = NULL; + free(host); + return ret; +} + +static void sdhci_pci_remove(struct pci_dev *pdev) +{ + struct sdhci_pci_host *host = pdev->dev.priv; + + sdhci_release_adma(&host->sdhci); + pci_clear_master(pdev); +} + +static struct pci_driver sdhci_driver = { + .name = "sdhci-pci", + .id_table = pci_ids, + .probe = sdhci_pci_probe, + .remove = sdhci_pci_remove, +}; + +static int __init sdhci_pci_driver_init(void) +{ + return pci_register_driver(&sdhci_driver); +} +module_init(sdhci_pci_driver_init); -- 2.47.3
