mmc: cqhci: support for command queue enabled host

This patch adds CMDQ support for command-queue compatible
hosts.

Command queue is added in eMMC-5.1 specification. This
enables the controller to process upto 32 requests at
a time.

Adrian Hunter contributed renaming to cqhci, recovery, suspend
and resume, cqhci_off, cqhci_wait_for_idle, and external timeout
handling.

Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>
Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>

drivers/mmc/host/Kconfig

@@ -857,6 +857,19 @@ config MMC_SUNXI
 	  This selects support for the SD/MMC Host Controller on
 	  Allwinner sunxi SoCs.
 
+config MMC_CQHCI
+	tristate "Command Queue Host Controller Interface support"
+	depends on HAS_DMA
+	help
+	  This selects the Command Queue Host Controller Interface (CQHCI)
+	  support present in host controllers of Qualcomm Technologies, Inc
+	  amongst others.
+	  This controller supports eMMC devices with command queue support.
+
+	  If you have a controller with this interface, say Y or M here.
+
+	  If unsure, say N.
+
 config MMC_TOSHIBA_PCI
 	tristate "Toshiba Type A SD/MMC Card Interface Driver"
 	depends on PCI

drivers/mmc/host/Makefile

@@ -92,6 +92,7 @@ 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
+obj-$(CONFIG_MMC_CQHCI)			+= cqhci.o
 
 ifeq ($(CONFIG_CB710_DEBUG),y)
 	CFLAGS-cb710-mmc	+= -DDEBUG

drivers/mmc/host/cqhci.h

@@ -0,0 +1,240 @@
+/* Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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 LINUX_MMC_CQHCI_H
+#define LINUX_MMC_CQHCI_H
+
+#include <linux/compiler.h>
+#include <linux/bitops.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+#include <linux/completion.h>
+#include <linux/wait.h>
+#include <linux/irqreturn.h>
+#include <asm/io.h>
+
+/* registers */
+/* version */
+#define CQHCI_VER			0x00
+#define CQHCI_VER_MAJOR(x)		(((x) & GENMASK(11, 8)) >> 8)
+#define CQHCI_VER_MINOR1(x)		(((x) & GENMASK(7, 4)) >> 4)
+#define CQHCI_VER_MINOR2(x)		((x) & GENMASK(3, 0))
+
+/* capabilities */
+#define CQHCI_CAP			0x04
+/* configuration */
+#define CQHCI_CFG			0x08
+#define CQHCI_DCMD			0x00001000
+#define CQHCI_TASK_DESC_SZ		0x00000100
+#define CQHCI_ENABLE			0x00000001
+
+/* control */
+#define CQHCI_CTL			0x0C
+#define CQHCI_CLEAR_ALL_TASKS		0x00000100
+#define CQHCI_HALT			0x00000001
+
+/* interrupt status */
+#define CQHCI_IS			0x10
+#define CQHCI_IS_HAC			BIT(0)
+#define CQHCI_IS_TCC			BIT(1)
+#define CQHCI_IS_RED			BIT(2)
+#define CQHCI_IS_TCL			BIT(3)
+
+#define CQHCI_IS_MASK (CQHCI_IS_TCC | CQHCI_IS_RED)
+
+/* interrupt status enable */
+#define CQHCI_ISTE			0x14
+
+/* interrupt signal enable */
+#define CQHCI_ISGE			0x18
+
+/* interrupt coalescing */
+#define CQHCI_IC			0x1C
+#define CQHCI_IC_ENABLE			BIT(31)
+#define CQHCI_IC_RESET			BIT(16)
+#define CQHCI_IC_ICCTHWEN		BIT(15)
+#define CQHCI_IC_ICCTH(x)		((x & 0x1F) << 8)
+#define CQHCI_IC_ICTOVALWEN		BIT(7)
+#define CQHCI_IC_ICTOVAL(x)		(x & 0x7F)
+
+/* task list base address */
+#define CQHCI_TDLBA			0x20
+
+/* task list base address upper */
+#define CQHCI_TDLBAU			0x24
+
+/* door-bell */
+#define CQHCI_TDBR			0x28
+
+/* task completion notification */
+#define CQHCI_TCN			0x2C
+
+/* device queue status */
+#define CQHCI_DQS			0x30
+
+/* device pending tasks */
+#define CQHCI_DPT			0x34
+
+/* task clear */
+#define CQHCI_TCLR			0x38
+
+/* send status config 1 */
+#define CQHCI_SSC1			0x40
+
+/* send status config 2 */
+#define CQHCI_SSC2			0x44
+
+/* response for dcmd */
+#define CQHCI_CRDCT			0x48
+
+/* response mode error mask */
+#define CQHCI_RMEM			0x50
+
+/* task error info */
+#define CQHCI_TERRI			0x54
+
+#define CQHCI_TERRI_C_INDEX(x)		((x) & GENMASK(5, 0))
+#define CQHCI_TERRI_C_TASK(x)		(((x) & GENMASK(12, 8)) >> 8)
+#define CQHCI_TERRI_C_VALID(x)		((x) & BIT(15))
+#define CQHCI_TERRI_D_INDEX(x)		(((x) & GENMASK(21, 16)) >> 16)
+#define CQHCI_TERRI_D_TASK(x)		(((x) & GENMASK(28, 24)) >> 24)
+#define CQHCI_TERRI_D_VALID(x)		((x) & BIT(31))
+
+/* command response index */
+#define CQHCI_CRI			0x58
+
+/* command response argument */
+#define CQHCI_CRA			0x5C
+
+#define CQHCI_INT_ALL			0xF
+#define CQHCI_IC_DEFAULT_ICCTH		31
+#define CQHCI_IC_DEFAULT_ICTOVAL	1
+
+/* attribute fields */
+#define CQHCI_VALID(x)			((x & 1) << 0)
+#define CQHCI_END(x)			((x & 1) << 1)
+#define CQHCI_INT(x)			((x & 1) << 2)
+#define CQHCI_ACT(x)			((x & 0x7) << 3)
+
+/* data command task descriptor fields */
+#define CQHCI_FORCED_PROG(x)		((x & 1) << 6)
+#define CQHCI_CONTEXT(x)		((x & 0xF) << 7)
+#define CQHCI_DATA_TAG(x)		((x & 1) << 11)
+#define CQHCI_DATA_DIR(x)		((x & 1) << 12)
+#define CQHCI_PRIORITY(x)		((x & 1) << 13)
+#define CQHCI_QBAR(x)			((x & 1) << 14)
+#define CQHCI_REL_WRITE(x)		((x & 1) << 15)
+#define CQHCI_BLK_COUNT(x)		((x & 0xFFFF) << 16)
+#define CQHCI_BLK_ADDR(x)		((x & 0xFFFFFFFF) << 32)
+
+/* direct command task descriptor fields */
+#define CQHCI_CMD_INDEX(x)		((x & 0x3F) << 16)
+#define CQHCI_CMD_TIMING(x)		((x & 1) << 22)
+#define CQHCI_RESP_TYPE(x)		((x & 0x3) << 23)
+
+/* transfer descriptor fields */
+#define CQHCI_DAT_LENGTH(x)		((x & 0xFFFF) << 16)
+#define CQHCI_DAT_ADDR_LO(x)		((x & 0xFFFFFFFF) << 32)
+#define CQHCI_DAT_ADDR_HI(x)		((x & 0xFFFFFFFF) << 0)
+
+struct cqhci_host_ops;
+struct mmc_host;
+struct cqhci_slot;
+
+struct cqhci_host {
+	const struct cqhci_host_ops *ops;
+	void __iomem *mmio;
+	struct mmc_host *mmc;
+
+	spinlock_t lock;
+
+	/* relative card address of device */
+	unsigned int rca;
+
+	/* 64 bit DMA */
+	bool dma64;
+	int num_slots;
+	int qcnt;
+
+	u32 dcmd_slot;
+	u32 caps;
+#define CQHCI_TASK_DESC_SZ_128		0x1
+
+	u32 quirks;
+#define CQHCI_QUIRK_SHORT_TXFR_DESC_SZ	0x1
+
+	bool enabled;
+	bool halted;
+	bool init_done;
+	bool activated;
+	bool waiting_for_idle;
+	bool recovery_halt;
+
+	size_t desc_size;
+	size_t data_size;
+
+	u8 *desc_base;
+
+	/* total descriptor size */
+	u8 slot_sz;
+
+	/* 64/128 bit depends on CQHCI_CFG */
+	u8 task_desc_len;
+
+	/* 64 bit on 32-bit arch, 128 bit on 64-bit */
+	u8 link_desc_len;
+
+	u8 *trans_desc_base;
+	/* same length as transfer descriptor */
+	u8 trans_desc_len;
+
+	dma_addr_t desc_dma_base;
+	dma_addr_t trans_desc_dma_base;
+
+	struct completion halt_comp;
+	wait_queue_head_t wait_queue;
+	struct cqhci_slot *slot;
+};
+
+struct cqhci_host_ops {
+	void (*dumpregs)(struct mmc_host *mmc);
+	void (*write_l)(struct cqhci_host *host, u32 val, int reg);
+	u32 (*read_l)(struct cqhci_host *host, int reg);
+	void (*enable)(struct mmc_host *mmc);
+	void (*disable)(struct mmc_host *mmc, bool recovery);
+};
+
+static inline void cqhci_writel(struct cqhci_host *host, u32 val, int reg)
+{
+	if (unlikely(host->ops->write_l))
+		host->ops->write_l(host, val, reg);
+	else
+		writel_relaxed(val, host->mmio + reg);
+}
+
+static inline u32 cqhci_readl(struct cqhci_host *host, int reg)
+{
+	if (unlikely(host->ops->read_l))
+		return host->ops->read_l(host, reg);
+	else
+		return readl_relaxed(host->mmio + reg);
+}
+
+struct platform_device;
+
+irqreturn_t cqhci_irq(struct mmc_host *mmc, u32 intmask, int cmd_error,
+		      int data_error);
+int cqhci_init(struct cqhci_host *cq_host, struct mmc_host *mmc, bool dma64);
+struct cqhci_host *cqhci_pltfm_init(struct platform_device *pdev);
+int cqhci_suspend(struct mmc_host *mmc);
+int cqhci_resume(struct mmc_host *mmc);
+
+#endif