[PATCH v2 1/1] mmc: sdhci-pci-dwc-mshc: synopsys dwc mshc support

[Prabu Thangamuthu]

Synopsys has DWC MSHC controller on HPAS-DX platform connected using PCIe
interface with SD card slot and eMMC device slots. This patch is to
enable SD cards connected on this platform. As Clock generation logic
is implemented using MMCM module of HAPS-DX platform, we have separate
functions to control the MMCM to generate required clocks with respect
to speed mode.

Signed-off-by: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
---
V2 - Removed sdhci-pci-dwc-mshc.h and moved into sdhci-pci-dwc-mshc.c
Fixed coding style issue.
Removed sdhci_snps_set_power and new approach to support eMMC device
voltages will be submitted after completeing validations.
V1 - Initial Patch.

MAINTAINERS | 7 +++
drivers/mmc/host/Makefile | 3 +-
drivers/mmc/host/sdhci-pci-core.c | 1 +
drivers/mmc/host/sdhci-pci-dwc-mshc.c | 88 +++++++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci-pci.h | 3 ++
5 files changed, 101 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/sdhci-pci-dwc-mshc.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 4863175..aba98b6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12684,6 +12684,13 @@ S: Maintained
F: drivers/mmc/host/sdhci*
F: include/linux/mmc/sdhci*

+SYNOPSYS SDHCI COMPLIANT DWC MSHC DRIVER
+M: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
+M: Manjunath M B <manjumb@xxxxxxxxxxxx>
+L: linux-mmc@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/mmc/host/sdhci-pci-dwc-mshc.c
+
SECURE DIGITAL HOST CONTROLLER INTERFACE (SDHCI) SAMSUNG DRIVER
M: Ben Dooks <ben-linux@xxxxxxxxx>
M: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 85dc132..20490f3 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -11,7 +11,8 @@ 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-arasan.o
+sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o sdhci-pci-arasan.o \
+ sdhci-pci-dwc-mshc.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-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 77dd352..ca1d4f7 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -1511,6 +1511,7 @@ static int amd_probe(struct sdhci_pci_chip *chip)
SDHCI_PCI_DEVICE(O2, SEABIRD0, o2),
SDHCI_PCI_DEVICE(O2, SEABIRD1, o2),
SDHCI_PCI_DEVICE(ARASAN, PHY_EMMC, arasan),
+ SDHCI_PCI_DEVICE(SYNOPSYS, DWC_MSHC, snps),
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-dwc-mshc.c b/drivers/mmc/host/sdhci-pci-dwc-mshc.c
new file mode 100644
index 0000000..0706055
--- /dev/null
+++ b/drivers/mmc/host/sdhci-pci-dwc-mshc.c
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SDHCI driver for Synopsys DWC_MSHC controller
+ *
+ * Copyright (C) 2018 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Authors:
+ * Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
+ * Manjunath M B <manjumb@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "sdhci.h"
+#include "sdhci-pci.h"
+
+#define SDHCI_VENDOR_PTR_R 0xE8
+
+/* Synopsys vendor specific registers */
+#define SDHC_GPIO_OUT 0x34
+#define SDHC_AT_CTRL_R 0x40
+#define SDHC_SW_TUNE_EN 0x00000010
+
+/* MMCM DRP */
+#define SDHC_MMCM_DIV_REG 0x1020
+#define DIV_REG_100_MHZ 0x1145
+#define DIV_REG_200_MHZ 0x1083
+#define SDHC_MMCM_CLKFBOUT 0x1024
+#define CLKFBOUT_100_MHZ 0x0000
+#define CLKFBOUT_200_MHZ 0x0080
+#define SDHC_CCLK_MMCM_RST 0x00000001
+
+static void sdhci_snps_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ u16 clk;
+ u32 reg, vendor_ptr;
+
+ vendor_ptr = sdhci_readw(host, SDHCI_VENDOR_PTR_R);
+
+ /* Disable software managed rx tuning */
+ reg = sdhci_readl(host, (SDHC_AT_CTRL_R + vendor_ptr));
+ reg &= ~SDHC_SW_TUNE_EN;
+ sdhci_writel(host, reg, (SDHC_AT_CTRL_R + vendor_ptr));
+
+ if (clock <= 52000000) {
+ sdhci_set_clock(host, clock);
+ } else {
+ /* Assert reset to MMCM */
+ reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
+ reg |= SDHC_CCLK_MMCM_RST;
+ sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr));
+
+ /* Configure MMCM */
+ if (clock == 100000000) {
+ sdhci_writel(host, DIV_REG_100_MHZ, SDHC_MMCM_DIV_REG);
+ sdhci_writel(host, CLKFBOUT_100_MHZ,
+ SDHC_MMCM_CLKFBOUT);
+ } else {
+ sdhci_writel(host, DIV_REG_200_MHZ, SDHC_MMCM_DIV_REG);
+ sdhci_writel(host, CLKFBOUT_200_MHZ,
+ SDHC_MMCM_CLKFBOUT);
+ }
+
+ /* De-assert reset to MMCM */
+ reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
+ reg &= ~SDHC_CCLK_MMCM_RST;
+ sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr));
+
+ /* Enable clock */
+ clk = SDHCI_PROG_CLOCK_MODE | SDHCI_CLOCK_INT_EN |
+ SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+ }
+}
+
+static const struct sdhci_ops sdhci_snps_ops = {
+ .set_clock = sdhci_snps_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,
+};
+
+const struct sdhci_pci_fixes sdhci_snps = {
+ .ops = &sdhci_snps_ops,
+};
diff --git a/drivers/mmc/host/sdhci-pci.h b/drivers/mmc/host/sdhci-pci.h
index db9cb54..60131b8 100644
--- a/drivers/mmc/host/sdhci-pci.h
+++ b/drivers/mmc/host/sdhci-pci.h
@@ -59,6 +59,8 @@
#define PCI_VENDOR_ID_ARASAN 0x16e6
#define PCI_DEVICE_ID_ARASAN_PHY_EMMC 0x0670

+#define PCI_DEVICE_ID_SYNOPSYS_DWC_MSHC 0xc202
+
/*
* PCI device class and mask
*/
@@ -182,5 +184,6 @@ static inline void *sdhci_pci_priv(struct sdhci_pci_slot *slot)
#endif

extern const struct sdhci_pci_fixes sdhci_arasan;
+extern const struct sdhci_pci_fixes sdhci_snps;

#endif /* __SDHCI_PCI_H */
-- 
1.9.1