mmc: cavium: Add MMC PCI driver for ThunderX SOCs

Add a platform driver for ThunderX ARM SOCs.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/Kconfig

@@ -622,6 +622,17 @@ config SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
 	help
 	  If you say yes here SD-Cards may work on the EZkit.
 
+config MMC_CAVIUM_THUNDERX
+	tristate "Cavium ThunderX SD/MMC Card Interface support"
+	depends on PCI && 64BIT && (ARM64 || COMPILE_TEST)
+	depends on GPIOLIB
+	depends on OF_ADDRESS
+	help
+	  This selects Cavium ThunderX SD/MMC Card Interface.
+	  If you have an Cavium ARM64 board with a Multimedia Card slot
+	  or builtin eMMC chip say Y or M here. If built as a module
+	  the module will be called thunderx_mmc.ko.
+
 config MMC_DW
 	tristate "Synopsys DesignWare Memory Card Interface"
 	depends on HAS_DMA

drivers/mmc/host/Makefile

@@ -42,6 +42,8 @@ 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
+thunderx-mmc-objs := cavium.o cavium-thunderx.o
+obj-$(CONFIG_MMC_CAVIUM_THUNDERX) += thunderx-mmc.o
 obj-$(CONFIG_MMC_DW)		+= dw_mmc.o
 obj-$(CONFIG_MMC_DW_PLTFM)	+= dw_mmc-pltfm.o
 obj-$(CONFIG_MMC_DW_EXYNOS)	+= dw_mmc-exynos.o

drivers/mmc/host/cavium-thunderx.c

@@ -0,0 +1,195 @@
+/*
+ * Driver for MMC and SSD cards for Cavium ThunderX SOCs.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2016 Cavium Inc.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/mmc/mmc.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include "cavium.h"
+
+static void thunder_mmc_acquire_bus(struct cvm_mmc_host *host)
+{
+	down(&host->mmc_serializer);
+}
+
+static void thunder_mmc_release_bus(struct cvm_mmc_host *host)
+{
+	up(&host->mmc_serializer);
+}
+
+static void thunder_mmc_int_enable(struct cvm_mmc_host *host, u64 val)
+{
+	writeq(val, host->base + MIO_EMM_INT(host));
+	writeq(val, host->base + MIO_EMM_INT_EN_SET(host));
+}
+
+static int thunder_mmc_register_interrupts(struct cvm_mmc_host *host,
+					   struct pci_dev *pdev)
+{
+	int nvec, ret, i;
+
+	nvec = pci_alloc_irq_vectors(pdev, 1, 9, PCI_IRQ_MSIX);
+	if (nvec < 0)
+		return nvec;
+
+	/* register interrupts */
+	for (i = 0; i < nvec; i++) {
+		ret = devm_request_irq(&pdev->dev, pci_irq_vector(pdev, i),
+				       cvm_mmc_interrupt,
+				       0, cvm_mmc_irq_names[i], host);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int thunder_mmc_probe(struct pci_dev *pdev,
+			     const struct pci_device_id *id)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct device_node *child_node;
+	struct cvm_mmc_host *host;
+	int ret, i = 0;
+
+	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+	if (!host)
+		return -ENOMEM;
+
+	pci_set_drvdata(pdev, host);
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	ret = pci_request_regions(pdev, KBUILD_MODNAME);
+	if (ret)
+		return ret;
+
+	host->base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
+	if (!host->base)
+		return -EINVAL;
+
+	/* On ThunderX these are identical */
+	host->dma_base = host->base;
+
+	host->reg_off = 0x2000;
+	host->reg_off_dma = 0x180;
+
+	host->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(host->clk))
+		return PTR_ERR(host->clk);
+
+	ret = clk_prepare_enable(host->clk);
+	if (ret)
+		return ret;
+	host->sys_freq = clk_get_rate(host->clk);
+
+	spin_lock_init(&host->irq_handler_lock);
+	sema_init(&host->mmc_serializer, 1);
+
+	host->dev = dev;
+	host->acquire_bus = thunder_mmc_acquire_bus;
+	host->release_bus = thunder_mmc_release_bus;
+	host->int_enable = thunder_mmc_int_enable;
+
+	host->big_dma_addr = true;
+	host->need_irq_handler_lock = true;
+	host->last_slot = -1;
+
+	ret = dma_set_mask(dev, DMA_BIT_MASK(48));
+	if (ret)
+		goto error;
+
+	/*
+	 * Clear out any pending interrupts that may be left over from
+	 * bootloader. Writing 1 to the bits clears them.
+	 */
+	writeq(127, host->base + MIO_EMM_INT_EN(host));
+	writeq(3, host->base + MIO_EMM_DMA_INT_ENA_W1C(host));
+
+	ret = thunder_mmc_register_interrupts(host, pdev);
+	if (ret)
+		goto error;
+
+	for_each_child_of_node(node, child_node) {
+		/*
+		 * mmc_of_parse and devm* require one device per slot.
+		 * Create a dummy device per slot and set the node pointer to
+		 * the slot. The easiest way to get this is using
+		 * of_platform_device_create.
+		 */
+		if (of_device_is_compatible(child_node, "mmc-slot")) {
+			host->slot_pdev[i] = of_platform_device_create(child_node, NULL,
+								       &pdev->dev);
+			if (!host->slot_pdev[i])
+				continue;
+
+			ret = cvm_mmc_of_slot_probe(&host->slot_pdev[i]->dev, host);
+			if (ret)
+				goto error;
+		}
+		i++;
+	}
+	dev_info(dev, "probed\n");
+	return 0;
+
+error:
+	clk_disable_unprepare(host->clk);
+	return ret;
+}
+
+static void thunder_mmc_remove(struct pci_dev *pdev)
+{
+	struct cvm_mmc_host *host = pci_get_drvdata(pdev);
+	u64 dma_cfg;
+	int i;
+
+	for (i = 0; i < CAVIUM_MAX_MMC; i++)
+		if (host->slot[i])
+			cvm_mmc_of_slot_remove(host->slot[i]);
+
+	dma_cfg = readq(host->dma_base + MIO_EMM_DMA_CFG(host));
+	dma_cfg &= ~MIO_EMM_DMA_CFG_EN;
+	writeq(dma_cfg, host->dma_base + MIO_EMM_DMA_CFG(host));
+
+	clk_disable_unprepare(host->clk);
+}
+
+static const struct pci_device_id thunder_mmc_id_table[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa010) },
+	{ 0, }  /* end of table */
+};
+
+static struct pci_driver thunder_mmc_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = thunder_mmc_id_table,
+	.probe = thunder_mmc_probe,
+	.remove = thunder_mmc_remove,
+};
+
+static int __init thunder_mmc_init_module(void)
+{
+	return pci_register_driver(&thunder_mmc_driver);
+}
+
+static void __exit thunder_mmc_exit_module(void)
+{
+	pci_unregister_driver(&thunder_mmc_driver);
+}
+
+module_init(thunder_mmc_init_module);
+module_exit(thunder_mmc_exit_module);
+
+MODULE_AUTHOR("Cavium Inc.");
+MODULE_DESCRIPTION("Cavium ThunderX eMMC Driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, thunder_mmc_id_table);

drivers/mmc/host/cavium.h

@@ -24,6 +24,11 @@
 
 /* DMA register addresses */
 #define MIO_EMM_DMA_CFG(x)	(0x00 + x->reg_off_dma)
+#define MIO_EMM_DMA_ADR(x)	(0x08 + x->reg_off_dma)
+#define MIO_EMM_DMA_INT(x)	(0x10 + x->reg_off_dma)
+#define MIO_EMM_DMA_INT_W1S(x)	(0x18 + x->reg_off_dma)
+#define MIO_EMM_DMA_INT_ENA_W1S(x) (0x20 + x->reg_off_dma)
+#define MIO_EMM_DMA_INT_ENA_W1C(x) (0x28 + x->reg_off_dma)
 
 /* register addresses */
 #define MIO_EMM_CFG(x)		(0x00 + x->reg_off)
@@ -39,6 +44,8 @@
 #define MIO_EMM_SAMPLE(x)	(0x90 + x->reg_off)
 #define MIO_EMM_STS_MASK(x)	(0x98 + x->reg_off)
 #define MIO_EMM_RCA(x)		(0xa0 + x->reg_off)
+#define MIO_EMM_INT_EN_SET(x)	(0xb0 + x->reg_off)
+#define MIO_EMM_INT_EN_CLR(x)	(0xb8 + x->reg_off)
 #define MIO_EMM_BUF_IDX(x)	(0xe0 + x->reg_off)
 #define MIO_EMM_BUF_DAT(x)	(0xe8 + x->reg_off)