The Arasan controller is based on a FPGA platform and has integrated phy with specific phy registers used during the 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://arasan.com/NF/eMMC5.1 PHY Programming in Linux.pdf. Signed-off-by: Atul Garg <agarg@xxxxxxxxxx> --- drivers/mmc/host/Makefile | 18 +- drivers/mmc/host/sdhci-pci-arasan.c | 325 ++++++++++++++++++++++++++++++++++++ drivers/mmc/host/sdhci-pci-arasan.h | 80 +++++++++ drivers/mmc/host/sdhci-pci-core.c | 16 ++ drivers/mmc/host/sdhci-pci.h | 4 + 5 files changed, 431 insertions(+), 12 deletions(-) create mode 100644 drivers/mmc/host/sdhci-pci-arasan.c create mode 100644 drivers/mmc/host/sdhci-pci-arasan.h diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile index 2b5a813..b9b2c6c 100644 --- a/drivers/mmc/host/Makefile +++ b/drivers/mmc/host/Makefile @@ -2,15 +2,14 @@ # Makefile for MMC/SD host controller drivers # -obj-$(CONFIG_MMC_ARMMMCI) += armmmci.o -armmmci-y := mmci.o -armmmci-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o +obj-$(CONFIG_MMC_ARMMMCI) += mmci.o +obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o obj-$(CONFIG_MMC_PXA) += pxamci.o obj-$(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-$(CONFIG_MMC_SDHCI_PXAV3) += sdhci-pxav3.o @@ -37,13 +36,9 @@ obj-$(CONFIG_MMC_S3C) += s3cmci.o obj-$(CONFIG_MMC_SDRICOH_CS) += sdricoh_cs.o obj-$(CONFIG_MMC_TMIO) += tmio_mmc.o obj-$(CONFIG_MMC_TMIO_CORE) += tmio_mmc_core.o -obj-$(CONFIG_MMC_SDHI) += renesas_sdhi_core.o -ifeq ($(subst m,y,$(CONFIG_MMC_SDHI_SYS_DMAC)),y) -obj-$(CONFIG_MMC_SDHI) += renesas_sdhi_sys_dmac.o -endif -ifeq ($(subst m,y,$(CONFIG_MMC_SDHI_INTERNAL_DMAC)),y) -obj-$(CONFIG_MMC_SDHI) += renesas_sdhi_internal_dmac.o -endif +tmio_mmc_core-y := tmio_mmc_pio.o +tmio_mmc_core-$(subst m,y,$(CONFIG_MMC_SDHI)) += tmio_mmc_dma.o +obj-$(CONFIG_MMC_SDHI) += sh_mobile_sdhi.o obj-$(CONFIG_MMC_CB710) += cb710-mmc.o obj-$(CONFIG_MMC_VIA_SDMMC) += via-sdmmc.o obj-$(CONFIG_SDH_BFIN) += bfin_sdh.o @@ -89,7 +84,6 @@ obj-$(CONFIG_MMC_SDHCI_MSM) += sdhci-msm.o obj-$(CONFIG_MMC_SDHCI_ST) += sdhci-st.o obj-$(CONFIG_MMC_SDHCI_MICROCHIP_PIC32) += sdhci-pic32.o obj-$(CONFIG_MMC_SDHCI_BRCMSTB) += sdhci-brcmstb.o -obj-$(CONFIG_MMC_SDHCI_OMAP) += sdhci-omap.o ifeq ($(CONFIG_CB710_DEBUG),y) CFLAGS-cb710-mmc += -DDEBUG diff --git a/drivers/mmc/host/sdhci-pci-arasan.c b/drivers/mmc/host/sdhci-pci-arasan.c new file mode 100644 index 0000000..57fbf8f --- /dev/null +++ b/drivers/mmc/host/sdhci-pci-arasan.c @@ -0,0 +1,325 @@ +/* + * 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" +#include "sdhci-pci-arasan.h" + +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); + timeout = 20; + do { + busy = sdhci_readw(host, HOST_PHY_ADDR_REG) & (1<<9); + if (!busy) + break; + mdelay(1); + } while (timeout--); + if (!timeout) + return -ENODEV; + 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); + *data = sdhci_readw(host, HOST_PHY_DATA_REG) & 0xFF; + sdhci_writew(host, ((0<<8) | offset), HOST_PHY_ADDR_REG); + timeout = 20; + do { + busy = sdhci_readw(host, HOST_PHY_ADDR_REG) & (1<<9); + if (!busy) + break; + mdelay(1); + } while (timeout--); + if (!timeout) + return -ENODEV; + *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; + u8 val; + + if (arasan_phy_write(host, 0, PHY_CONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPADCONTROL1, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | RETB_ENABLE, PHY_IOPADCONTROL1)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPADCONTROL2, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | RTRIM_ENABLE, PHY_IOPADCONTROL2)) + return -ENODEV; + mdelay(10); + + if (arasan_phy_read(host, PHY_IOPADSTATUS, &val)) { + if (!(val & CALDONE_MASK)) { + dev_err(&pdev->dev, "Phy calibration not done\n"); + return -ENODEV; + } + } + if (arasan_phy_read(host, PHY_IOPADCONTROL1, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PDB_ENABLE, PHY_IOPADCONTROL1)) + return -ENODEV; + mdelay(10); + + if (arasan_phy_read(host, PHY_IOPADSTATUS, &val)) { + if (!(val & CALDONE_MASK)) { + dev_err(&pdev->dev, "Phy calibration not done\n"); + return -ENODEV; + } + } + if (arasan_phy_read(host, PHY_IORENCONTROL1, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | REN_CMD | REN_STRB, PHY_IORENCONTROL1)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPUCONTROL1, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PU_CMD, PHY_IOPUCONTROL1)) + return -ENODEV; + if (arasan_phy_read(host, PHY_CMDCONTROL, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PDB_CMD, PHY_CMDCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IORENCONTROL2, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | REN_DAT, PHY_IORENCONTROL2)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPUCONTROL2, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PU_DAT, PHY_IOPUCONTROL2)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DATACONTROL, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PDB_DAT, PHY_DATACONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_STROBECONTROL, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PDB_STRB, PHY_STROBECONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_CLKCONTROL, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | PDB_CLK, PHY_CLKCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_CLKBUFSELECT, &val)) + return -ENODEV; + if (arasan_phy_write(host, val | 0x7, PHY_CLKBUFSELECT)) + return -ENODEV; + if (arasan_phy_write(host, 0x4, PHY_MODECONTROL)) + return -ENODEV; + return 0; +} + + +static int arasan_set_phy(struct sdhci_host *host) +{ + u8 clk_sel; + static u32 chg_clk; + u8 val; + u8 otap, itap, dll_sts, io_pad; + + if (chg_clk != host->mmc->ios.clock) { + chg_clk = host->mmc->ios.clock; + if (host->mmc->ios.clock == 200000000) + clk_sel = 0; + else if (host->mmc->ios.clock == 100000000) + clk_sel = 2; + else if (host->mmc->ios.clock == 50000000) + clk_sel = 1; + else + clk_sel = 0; + /* Change phy settings only if there is a change in clock */ + goto set_phy; + } else + return 0; +set_phy: + if (host->mmc_host_ops.hs400_enhanced_strobe) { + if (arasan_phy_write(host, 0x1, PHY_MODECONTROL)) + return -ENODEV; + otap = ((0x2<<1) | OTAP_DLY_EN); + if (arasan_phy_write(host, otap, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, DLL_TRIM, PHY_DLLTRIM)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + dll_sts = (clk_sel<<5) | DLL_ENABLE; + if (arasan_phy_write(host, dll_sts, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + } else { + switch (host->mmc->ios.timing) { + case MMC_TIMING_LEGACY: + if (arasan_phy_write(host, 0x4, PHY_MODECONTROL)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + break; + case MMC_TIMING_MMC_HS: + if (arasan_phy_write(host, 0, PHY_MODECONTROL)) + return -ENODEV; + otap = ((0x2<<3) | OTAP_DLY_EN); + if (arasan_phy_write(host, otap, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + itap = ((0x2<<1) | ITAP_DLY_EN); + if (arasan_phy_write(host, itap, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, DLL_TRIM, PHY_DLLTRIM)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + dll_sts = (clk_sel<<5) | DLL_ENABLE; + if (arasan_phy_write(host, dll_sts, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + break; + case MMC_TIMING_MMC_HS200: + if (arasan_phy_write(host, 0, PHY_MODECONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPADCONTROL1, &val)) + return -ENODEV; + io_pad = val | (host->mmc->ios.drv_type<<2); + if (arasan_phy_write(host, io_pad, PHY_IOPADCONTROL1)) + return -ENODEV; + otap = ((0x2<<1) | OTAP_DLY_EN); + if (arasan_phy_write(host, otap, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, DLL_TRIM, PHY_DLLTRIM)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + dll_sts = (clk_sel<<5) | DLL_ENABLE; + if (arasan_phy_write(host, dll_sts, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + break; + case MMC_TIMING_UHS_DDR50: + if (arasan_phy_write(host, 0x8, PHY_MODECONTROL)) + return -ENODEV; + otap = ((0x2<<3) | OTAP_DLY_EN); + if (arasan_phy_write(host, otap, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + itap = ((0x2<<1) | ITAP_DLY_EN); + if (arasan_phy_write(host, itap, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, DLL_TRIM, PHY_DLLTRIM)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + dll_sts = (clk_sel<<5) | DLL_ENABLE; + if (arasan_phy_write(host, dll_sts, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + break; + case MMC_TIMING_MMC_HS400: + if (arasan_phy_write(host, 0x2, PHY_MODECONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_IOPADCONTROL1, &val)) + return -ENODEV; + io_pad = val | (host->mmc->ios.drv_type<<2); + if (arasan_phy_write(host, io_pad, PHY_IOPADCONTROL1)) + return -ENODEV; + otap = ((0x2<<1) | OTAP_DLY_EN); + if (arasan_phy_write(host, otap, PHY_OUTPUTTAPDELAY)) + return -ENODEV; + itap = ((0xA<<1) | ITAP_DLY_EN); + if (arasan_phy_write(host, itap, PHY_INPUTTAPDELAY)) + return -ENODEV; + if (arasan_phy_write(host, DLL_TRIM, PHY_DLLTRIM)) + return -ENODEV; + if (arasan_phy_write(host, 0, PHY_DLLCONTROL)) + return -ENODEV; + dll_sts = (clk_sel<<5) | DLL_ENABLE; + if (arasan_phy_write(host, dll_sts, PHY_DLLCONTROL)) + return -ENODEV; + if (arasan_phy_read(host, PHY_DLLCONTROL, &val)) + return -ENODEV; + if (arasan_phy_write(host, 0x0E, PHY_CLKBUFSELECT)) + return -ENODEV; + break; + default: + break; + } + } + return 0; +} + +int arasan_pci_probe(struct sdhci_pci_chip *chip) +{ + struct pci_dev *dev; + + dev = pci_get_device(PCI_VENDOR_ID_ARASAN, + PCI_DEVICE_ID_ARASAN_PHY_EMMC, NULL); + return 0; +} +int arasan_pci_probe_slot(struct sdhci_pci_slot *slot) +{ + int err; + + 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); + + /*Change phy settings for the new clock */ + arasan_set_phy(host); +} diff --git a/drivers/mmc/host/sdhci-pci-arasan.h b/drivers/mmc/host/sdhci-pci-arasan.h new file mode 100644 index 0000000..819ed93 --- /dev/null +++ b/drivers/mmc/host/sdhci-pci-arasan.h @@ -0,0 +1,80 @@ +/* + * 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. + * + */ + +#ifndef __SDHCI_PCI_ARASAN_H +#define __SDHCI_PCI_ARASAN_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 + +#define PHY_DLLCONTROL 0x00 +#define PHY_IOPADCONTROL1 0x01 +#define PHY_IOPADCONTROL2 0x02 +#define PHY_IOPADSTATUS 0x03 +#define PHY_IOODCONTROL1 0x04 +#define PHY_IOODCONTROL2 0x05 +#define PHY_IORENCONTROL1 0x06 +#define PHY_IORENCONTROL2 0x07 +#define PHY_IOPUCONTROL1 0x08 +#define PHY_IOPUCONTROL2 0x09 +#define PHY_IOODRELCONTROL1 0x0A +#define PHY_IOODRELCONTROL2 0x0B +#define PHY_INPUTTAPDELAY 0x0C +#define PHY_OUTPUTTAPDELAY 0x0D +#define PHY_STROBESELECT 0x0E +#define PHY_CLKBUFSELECT 0x0F +#define PHY_MODECONTROL 0x11 +#define PHY_DLLTRIM 0x12 +#define PHY_LDOCONTROL 0x1F +#define PHY_CMDCONTROL 0x20 +#define PHY_DATACONTROL 0x21 +#define PHY_STROBECONTROL 0x22 +#define PHY_CLKCONTROL 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 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 + +extern int arasan_pci_probe_slot(struct sdhci_pci_slot *slot); + +extern int arasan_pci_probe(struct sdhci_pci_chip *chip); + +extern void arasan_sdhci_set_clock(struct sdhci_host *host, unsigned int clock); + +#endif /* __SDHCI_PCI_ARASAN_H */ diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c index 5f3f7b5..3bd77dd 100644 --- a/drivers/mmc/host/sdhci-pci-core.c +++ b/drivers/mmc/host/sdhci-pci-core.c @@ -1112,6 +1112,21 @@ 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_pci_set_bus_width, + .reset = sdhci_reset, + .set_uhs_signaling = sdhci_set_uhs_signaling, +}; + +static const struct sdhci_pci_fixes sdhci_arasan = { + .probe = arasan_pci_probe, + .probe_slot = arasan_pci_probe_slot, + .ops = &arasan_sdhci_pci_ops, +}; + + /*AMD chipset generation*/ enum amd_chipset_gen { AMD_CHIPSET_BEFORE_ML, @@ -1314,6 +1329,7 @@ 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 3c1dd79..e370836 100644 --- a/drivers/mmc/host/sdhci-pci.h +++ b/drivers/mmc/host/sdhci-pci.h @@ -48,6 +48,10 @@ #define PCI_SUBDEVICE_ID_NI_7884 0x7884 +/* Arasan Device IDs */ +#define PCI_VENDOR_ID_ARASAN 0x16e6 +#define PCI_DEVICE_ID_ARASAN_PHY_EMMC 0x0670 + /* * PCI device class and mask */ -- 2.7.4 -- ATTENTION: The information contained in this message may be legally privileged and confidential. 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