[PATCH v1 1/2] soc: aspeed: add BMC-side PCIe BMC device driver

@@ -4,6 +4,15 @@ if ARCH_ASPEED || COMPILE_TEST
 
 menu "ASPEED SoC drivers"
 
+config ASPEED_BMC_DEV
+	tristate "ASPEED BMC Device"
+	default n
+	help
+	  Enable support for the ASPEED AST2600/AST2700 BMC Device.
+	  This exposes the BMC to the host over PCIe,
+	  providing a shared-memory BAR, host-to-BMC and BMC-to-host
+	  message queues with doorbell interrupts and PCIe-to-LPC bridge.
+
 config ASPEED_LPC_CTRL
 	tristate "ASPEED LPC firmware cycle control"
 	select REGMAP

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_ASPEED_BMC_DEV)		+= aspeed-bmc-dev.o
 obj-$(CONFIG_ASPEED_LPC_CTRL)		+= aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP)		+= aspeed-lpc-snoop.o
 obj-$(CONFIG_ASPEED_UART_ROUTING)	+= aspeed-uart-routing.o

@@ -0,0 +1,701 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (C) ASPEED Technology Inc.
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#include <linux/regmap.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/syscon.h>
+#include <linux/dma-mapping.h>
+#include <linux/miscdevice.h>
+
+#define SCU_TRIGGER_MSI
+
+/* AST2600 SCU */
+#define ASPEED_SCU04			0x04
+#define AST2600A3_SCU04				0x05030303
+#define ASPEED_SCUC20			0xC20
+#define ASPEED_SCUC24			0xC24
+#define MSI_ROUTING_MASK			GENMASK(11, 10)
+#define PCIDEV1_INTX_MSI_HOST2BMC_EN		BIT(18)
+#define MSI_ROUTING_PCIe2LPC_PCIDEV0		(0x1 << 10)
+#define MSI_ROUTING_PCIe2LPC_PCIDEV1		(0x2 << 10)
+/* AST2700 SCU */
+#define SCU0_REVISION_ID		0x0
+#define REVISION_ID				GENMASK(23, 16)
+#define SCU0_PCIE_CONF_CTRL		0x970
+/* Host2BMC */
+#define ASPEED_BMC_MEM_BAR			0xF10
+#define  PCIE2PCI_MEM_BAR_ENABLE		BIT(1)
+#define  HOST2BMC_MEM_BAR_ENABLE		BIT(0)
+#define ASPEED_BMC_MEM_BAR_REMAP	0xF18
+
+#define ASPEED_BMC_SHADOW_CTRL		0xF50
+#define  READ_ONLY_MASK				BIT(31)
+#define  MASK_BAR1					BIT(2)
+#define  MASK_BAR0					BIT(1)
+#define  SHADOW_CFG					BIT(0)
+
+#define ASPEED_BMC_HOST2BMC_Q1		0xA000
+#define ASPEED_BMC_HOST2BMC_Q2		0xA010
+#define ASPEED_BMC_BMC2HOST_Q1		0xA020
+#define ASPEED_BMC_BMC2HOST_Q2		0xA030
+#define ASPEED_BMC_BMC2HOST_STS		0xA040
+#define	 BMC2HOST_INT_STS_DOORBELL		BIT(31)
+#define	 BMC2HOST_ENABLE_INTB			BIT(30)
+#define	 BMC2HOST_Q1_FULL				BIT(27)
+#define	 BMC2HOST_Q1_EMPTY				BIT(26)
+#define	 BMC2HOST_Q2_FULL				BIT(25)
+#define	 BMC2HOST_Q2_EMPTY				BIT(24)
+#define	 BMC2HOST_Q1_FULL_UNMASK		BIT(23)
+#define	 BMC2HOST_Q1_EMPTY_UNMASK		BIT(22)
+#define	 BMC2HOST_Q2_FULL_UNMASK		BIT(21)
+#define	 BMC2HOST_Q2_EMPTY_UNMASK		BIT(20)
+
+#define ASPEED_BMC_HOST2BMC_STS		0xA044
+#define	 HOST2BMC_INT_STS_DOORBELL		BIT(31)
+#define	 HOST2BMC_ENABLE_INTB			BIT(30)
+#define	 HOST2BMC_Q1_FULL				BIT(27)
+#define	 HOST2BMC_Q1_EMPTY				BIT(26)
+#define	 HOST2BMC_Q2_FULL				BIT(25)
+#define	 HOST2BMC_Q2_EMPTY				BIT(24)
+#define	 HOST2BMC_Q1_FULL_UNMASK		BIT(23)
+#define	 HOST2BMC_Q1_EMPTY_UNMASK		BIT(22)
+#define	 HOST2BMC_Q2_FULL_UNMASK		BIT(21)
+#define	 HOST2BMC_Q2_EMPTY_UNMASK		BIT(20)
+
+#define ASPEED_SCU_PCIE_CONF_CTRL	0xC20
+#define  SCU_PCIE_CONF_BMC_DEV_EN			 BIT(8)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_MMIO		 BIT(9)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_MSI		 BIT(11)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_IRQ		 BIT(13)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_DMA		 BIT(14)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_E2L		 BIT(15)
+#define  SCU_PCIE_CONF_BMC_DEV_EN_LPC_DECODE BIT(21)
+
+#define ASPEED_SCU_BMC_DEV_CLASS	0xC68
+
+#define ASPEED_QUEUE_NUM 2
+enum queue_index {
+	QUEUE1 = 0,
+	QUEUE2,
+};
+
+struct aspeed_platform {
+	int (*init)(struct platform_device *pdev);
+	ssize_t (*queue_rx)(struct file *filp, struct kobject *kobj,
+			    const struct bin_attribute *attr, char *buf, loff_t off, size_t count);
+	ssize_t (*queue_tx)(struct file *filp, struct kobject *kobj,
+			    const struct bin_attribute *attr, char *buf, loff_t off, size_t count);
+};
+
+struct aspeed_queue_message {
+	/* Queue waiters for idle engine */
+	wait_queue_head_t tx_wait;
+	wait_queue_head_t rx_wait;
+	struct kernfs_node *kn;
+	struct bin_attribute bin;
+	int index;
+	struct aspeed_bmc_device *bmc_device;
+};
+
+struct aspeed_bmc_device {
+	unsigned char *host2bmc_base_virt;
+	struct device *dev;
+	struct miscdevice miscdev;
+	int id;
+	void __iomem *reg_base;
+	dma_addr_t bmc_mem_phy;
+	phys_addr_t bmc_mem_size;
+	void *bmc_mem_cpu;
+
+	int pcie2lpc;
+	int irq;
+
+	struct aspeed_queue_message queue[ASPEED_QUEUE_NUM];
+
+	const struct aspeed_platform *platform;
+
+	/* AST2700 */
+	struct regmap *device;
+	struct regmap *e2m;
+
+	struct regmap *scu;
+	int pcie_irq;
+};
+
+static struct aspeed_bmc_device *file_aspeed_bmc_device(struct file *file)
+{
+	return container_of(file->private_data, struct aspeed_bmc_device,
+			miscdev);
+}
+
+static int aspeed_bmc_device_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct aspeed_bmc_device *bmc_device = file_aspeed_bmc_device(file);
+	unsigned long vsize = vma->vm_end - vma->vm_start;
+
+	if (vsize > bmc_device->bmc_mem_size)
+		return -EINVAL;
+
+	return dma_mmap_coherent(bmc_device->dev, vma,
+				 bmc_device->bmc_mem_cpu,
+				 bmc_device->bmc_mem_phy,
+				 bmc_device->bmc_mem_size);
+
+}
+
+static const struct file_operations aspeed_bmc_device_fops = {
+	.owner		= THIS_MODULE,
+	.mmap		= aspeed_bmc_device_mmap,
+};
+
+static ssize_t aspeed_ast2600_queue_rx(struct file *filp, struct kobject *kobj,
+				       const struct bin_attribute *attr, char *buf, loff_t off,
+				       size_t count)
+{
+	struct aspeed_queue_message *queue = attr->private;
+	struct aspeed_bmc_device *bmc_device = queue->bmc_device;
+	int index = queue->index;
+	u32 *data = (u32 *)buf;
+	u32 scu_id;
+	int ret;
+
+	ret = wait_event_interruptible(queue->rx_wait,
+				       !(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) &
+				       ((index == QUEUE1) ? HOST2BMC_Q1_EMPTY : HOST2BMC_Q2_EMPTY)));
+	if (ret)
+		return -EINTR;
+
+	data[0] = readl(bmc_device->reg_base +
+			((index == QUEUE1) ? ASPEED_BMC_HOST2BMC_Q1 : ASPEED_BMC_HOST2BMC_Q2));
+
+	regmap_read(bmc_device->scu, ASPEED_SCU04, &scu_id);
+	if (scu_id == AST2600A3_SCU04) {
+		writel(BMC2HOST_INT_STS_DOORBELL | BMC2HOST_ENABLE_INTB,
+		       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+	} else {
+		//A0 : BIT(12) A1 : BIT(15)
+		regmap_update_bits(bmc_device->scu, 0x560, BIT(15), BIT(15));
+		regmap_update_bits(bmc_device->scu, 0x560, BIT(15), 0);
+	}
+
+	return sizeof(u32);
+}
+
+static ssize_t aspeed_ast2600_queue_tx(struct file *filp, struct kobject *kobj,
+				       const struct bin_attribute *attr, char *buf, loff_t off,
+				       size_t count)
+{
+	struct aspeed_queue_message *queue = attr->private;
+	struct aspeed_bmc_device *bmc_device = queue->bmc_device;
+	int index = queue->index;
+	u32 tx_buff;
+	u32 scu_id;
+	int ret;
+
+	if (count != sizeof(u32))
+		return -EINVAL;
+
+	ret = wait_event_interruptible(queue->tx_wait,
+				       !(readl(bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS) &
+				       ((index == QUEUE1) ? BMC2HOST_Q1_FULL : BMC2HOST_Q2_FULL)));
+	if (ret)
+		return -EINTR;
+
+	memcpy(&tx_buff, buf, 4);
+	writel(tx_buff, bmc_device->reg_base + ((index == QUEUE1) ? ASPEED_BMC_BMC2HOST_Q1 :
+								    ASPEED_BMC_BMC2HOST_Q2));
+
+	/* trigger to host
+	 * Only After AST2600A3 support DoorBell MSI
+	 */
+	regmap_read(bmc_device->scu, ASPEED_SCU04, &scu_id);
+	if (scu_id == AST2600A3_SCU04) {
+		writel(BMC2HOST_INT_STS_DOORBELL | BMC2HOST_ENABLE_INTB,
+		       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+	} else {
+		//A0 : BIT(12) A1 : BIT(15)
+		regmap_update_bits(bmc_device->scu, 0x560, BIT(15), BIT(15));
+		regmap_update_bits(bmc_device->scu, 0x560, BIT(15), 0);
+	}
+
+	return sizeof(u32);
+}
+
+static ssize_t aspeed_ast2700_queue_rx(struct file *filp, struct kobject *kobj,
+				       const struct bin_attribute *attr, char *buf, loff_t off,
+				       size_t count)
+{
+	struct aspeed_queue_message *queue = attr->private;
+	struct aspeed_bmc_device *bmc_device = queue->bmc_device;
+	int index = queue->index;
+	u32 *data = (u32 *)buf;
+	int ret;
+
+	ret = wait_event_interruptible(queue->rx_wait,
+				       !(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) &
+				       ((index == QUEUE1) ? HOST2BMC_Q1_EMPTY : HOST2BMC_Q2_EMPTY)));
+	if (ret)
+		return -EINTR;
+
+	data[0] = readl(bmc_device->reg_base +
+			((index == QUEUE1) ? ASPEED_BMC_HOST2BMC_Q1 : ASPEED_BMC_HOST2BMC_Q2));
+
+	writel(BMC2HOST_INT_STS_DOORBELL | BMC2HOST_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+
+	return sizeof(u32);
+}
+
+static ssize_t aspeed_ast2700_queue_tx(struct file *filp, struct kobject *kobj,
+				       const struct bin_attribute *attr, char *buf, loff_t off,
+				       size_t count)
+{
+	struct aspeed_queue_message *queue = attr->private;
+	struct aspeed_bmc_device *bmc_device = queue->bmc_device;
+	int index = queue->index;
+	u32 tx_buff;
+	int ret;
+
+	if (count != sizeof(u32))
+		return -EINVAL;
+
+	ret = wait_event_interruptible(queue->tx_wait,
+				       !(readl(bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS) &
+				       ((index == QUEUE1) ? BMC2HOST_Q1_FULL : BMC2HOST_Q2_FULL)));
+	if (ret)
+		return -EINTR;
+
+	memcpy(&tx_buff, buf, 4);
+	writel(tx_buff, bmc_device->reg_base + ((index == QUEUE1) ? ASPEED_BMC_BMC2HOST_Q1 :
+								    ASPEED_BMC_BMC2HOST_Q2));
+
+	writel(BMC2HOST_INT_STS_DOORBELL | BMC2HOST_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+
+	return sizeof(u32);
+}
+
+/* AST2600 */
+static irqreturn_t aspeed_bmc_dev_pcie_isr(int irq, void *dev_id)
+{
+	struct aspeed_bmc_device *bmc_device = dev_id;
+
+	while (!(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) & HOST2BMC_Q1_EMPTY))
+		readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_Q1);
+
+	while (!(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) & HOST2BMC_Q2_EMPTY))
+		readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_Q2);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t aspeed_bmc_dev_isr(int irq, void *dev_id)
+{
+	struct aspeed_bmc_device *bmc_device = dev_id;
+	u32 host2bmc_q_sts = readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS);
+
+	if (host2bmc_q_sts & HOST2BMC_INT_STS_DOORBELL)
+		writel(HOST2BMC_INT_STS_DOORBELL, bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS);
+
+	if (host2bmc_q_sts & HOST2BMC_ENABLE_INTB)
+		writel(HOST2BMC_ENABLE_INTB, bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS);
+
+	if (host2bmc_q_sts & HOST2BMC_Q1_FULL)
+		dev_info(bmc_device->dev, "Q1 Full\n");
+
+	if (host2bmc_q_sts & HOST2BMC_Q2_FULL)
+		dev_info(bmc_device->dev, "Q2 Full\n");
+
+	if (!(readl(bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS) & BMC2HOST_Q1_FULL))
+		wake_up_interruptible(&bmc_device->queue[QUEUE1].tx_wait);
+
+	if (!(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) & HOST2BMC_Q1_EMPTY))
+		wake_up_interruptible(&bmc_device->queue[QUEUE1].rx_wait);
+
+	if (!(readl(bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS) & BMC2HOST_Q2_FULL))
+		wake_up_interruptible(&bmc_device->queue[QUEUE2].tx_wait);
+
+	if (!(readl(bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS) & HOST2BMC_Q2_EMPTY))
+		wake_up_interruptible(&bmc_device->queue[QUEUE2].rx_wait);
+
+	return IRQ_HANDLED;
+}
+
+static int aspeed_ast2600_init(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	u32 pcie_config_ctl = SCU_PCIE_CONF_BMC_DEV_EN_IRQ |
+			      SCU_PCIE_CONF_BMC_DEV_EN_MMIO | SCU_PCIE_CONF_BMC_DEV_EN;
+	u32 scu_id;
+
+	bmc_device->scu = syscon_regmap_lookup_by_phandle(dev->of_node, "aspeed,scu");
+	if (IS_ERR(bmc_device->scu)) {
+		dev_err(&pdev->dev, "failed to find SCU regmap\n");
+		return PTR_ERR(bmc_device->scu);
+	}
+
+	if (bmc_device->pcie2lpc)
+		pcie_config_ctl |= SCU_PCIE_CONF_BMC_DEV_EN_E2L |
+				   SCU_PCIE_CONF_BMC_DEV_EN_LPC_DECODE;
+
+	regmap_update_bits(bmc_device->scu, ASPEED_SCU_PCIE_CONF_CTRL,
+			   pcie_config_ctl, pcie_config_ctl);
+
+	/* update class code to others as it is a MFD device */
+	regmap_write(bmc_device->scu, ASPEED_SCU_BMC_DEV_CLASS, 0xff000000);
+
+#ifdef SCU_TRIGGER_MSI
+	//SCUC24[17]: Enable PCI device 1 INTx/MSI from SCU560[15]. Will be added in next version
+	regmap_update_bits(bmc_device->scu, ASPEED_SCUC20, BIT(11) | BIT(14), BIT(11) | BIT(14));
+
+	regmap_read(bmc_device->scu, ASPEED_SCU04, &scu_id);
+	if (scu_id == AST2600A3_SCU04)
+		regmap_update_bits(bmc_device->scu, ASPEED_SCUC24,
+				   PCIDEV1_INTX_MSI_HOST2BMC_EN | MSI_ROUTING_MASK,
+				   PCIDEV1_INTX_MSI_HOST2BMC_EN | MSI_ROUTING_PCIe2LPC_PCIDEV1);
+	else
+		regmap_update_bits(bmc_device->scu, ASPEED_SCUC24,
+				   BIT(17) | BIT(14) | BIT(11), BIT(17) | BIT(14) | BIT(11));
+#else
+	//SCUC24[18]: Enable PCI device 1 INTx/MSI from Host-to-BMC controller.
+	regmap_update_bits(bmc_device->scu, 0xc24, BIT(18) | BIT(14), BIT(18) | BIT(14));
+#endif
+
+	writel((~(bmc_device->bmc_mem_size - 1) & 0xFFFFFFFF) | HOST2BMC_MEM_BAR_ENABLE,
+	       bmc_device->reg_base + ASPEED_BMC_MEM_BAR);
+	writel(bmc_device->bmc_mem_phy, bmc_device->reg_base + ASPEED_BMC_MEM_BAR_REMAP);
+
+	//Setting BMC to Host Q register
+	writel(BMC2HOST_Q2_FULL_UNMASK | BMC2HOST_Q1_FULL_UNMASK | BMC2HOST_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+	writel(HOST2BMC_Q2_FULL_UNMASK |  HOST2BMC_Q1_FULL_UNMASK | HOST2BMC_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS);
+
+	return 0;
+}
+
+static int aspeed_ast2700_init(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	u32 pcie_config_ctl;
+	u32 scu_id;
+	int i;
+
+	bmc_device->device = syscon_regmap_lookup_by_phandle(dev->of_node, "aspeed,device");
+	if (IS_ERR(bmc_device->device)) {
+		dev_err(&pdev->dev, "failed to find device regmap\n");
+		return PTR_ERR(bmc_device->device);
+	}
+
+	bmc_device->e2m = syscon_regmap_lookup_by_phandle(dev->of_node, "aspeed,e2m");
+	if (IS_ERR(bmc_device->e2m)) {
+		dev_err(&pdev->dev, "failed to find e2m regmap\n");
+		return PTR_ERR(bmc_device->e2m);
+	}
+
+	bmc_device->scu = syscon_regmap_lookup_by_phandle(dev->of_node, "aspeed,scu");
+	if (IS_ERR(bmc_device->scu)) {
+		dev_err(&pdev->dev, "failed to find SCU regmap\n");
+		return PTR_ERR(bmc_device->scu);
+	}
+
+	if (bmc_device->pcie2lpc) {
+		pcie_config_ctl = SCU_PCIE_CONF_BMC_DEV_EN_E2L |
+				  SCU_PCIE_CONF_BMC_DEV_EN_LPC_DECODE;
+		regmap_update_bits(bmc_device->scu, SCU0_PCIE_CONF_CTRL,
+				   pcie_config_ctl, pcie_config_ctl);
+	}
+
+	/* update class code to others as it is a MFD device */
+	regmap_write(bmc_device->device, 0x18, 0xff000027);
+
+	/* MSI */
+	regmap_update_bits(bmc_device->device, 0x74, GENMASK(7, 4), BIT(7) | (5 << 4));
+	/* EnPCIaMSI:BIT(25), EnPCIaIntA:BIT(17), EnPCIaMst:BIT(9), EnPCIaDev:BIT(1) */
+	regmap_read(bmc_device->scu, SCU0_REVISION_ID, &scu_id);
+	if (scu_id & REVISION_ID)
+		regmap_update_bits(bmc_device->device, 0x70,
+				   BIT(25) | BIT(17) | BIT(9) | BIT(1),
+				   BIT(25) | BIT(17) | BIT(9) | BIT(1));
+	else
+		/* Disable MSI[bit25] in ast2700A0 int only */
+		regmap_update_bits(bmc_device->device, 0x70,
+				   BIT(17) | BIT(9) | BIT(1),
+				   BIT(25) | BIT(17) | BIT(9) | BIT(1));
+
+	/* bar size check for 4k align */
+	for (i = 1; i < 16; i++) {
+		if ((bmc_device->bmc_mem_size / 4096) == (1 << (i - 1)))
+			break;
+	}
+	if (i == 16) {
+		i = 0;
+		dev_warn(bmc_device->dev,
+			 "Bar size not align for 4K : %dK\n", (u32)bmc_device->bmc_mem_size / 1024);
+	}
+
+	/*
+	 * BAR assign in scu
+	 * ((bar_mem / 4k) << 8) | per_size
+	 */
+	regmap_write(bmc_device->device, 0x1c, ((bmc_device->bmc_mem_phy) >> 4) | i);
+
+	if (bmc_device->id == 0)
+		/* Node 0 Bar 0 */
+		regmap_write(bmc_device->e2m, 0x108, ((bmc_device->bmc_mem_phy) >> 4) | i);
+	else
+		/* Node 1 Bar 0 */
+		regmap_write(bmc_device->e2m, 0x128, ((bmc_device->bmc_mem_phy) >> 4) | i);
+
+	/* Setting BMC to Host Q register */
+	writel(BMC2HOST_Q2_FULL_UNMASK | BMC2HOST_Q1_FULL_UNMASK | BMC2HOST_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_BMC2HOST_STS);
+	writel(HOST2BMC_Q2_FULL_UNMASK | HOST2BMC_Q1_FULL_UNMASK | HOST2BMC_ENABLE_INTB,
+	       bmc_device->reg_base + ASPEED_BMC_HOST2BMC_STS);
+
+	return 0;
+}
+
+static int aspeed_bmc_device_setup_queue(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	int ret, i;
+
+	for (i = 0; i < ASPEED_QUEUE_NUM; i++) {
+		struct aspeed_queue_message *queue = &bmc_device->queue[i];
+
+		init_waitqueue_head(&queue->tx_wait);
+		init_waitqueue_head(&queue->rx_wait);
+
+		sysfs_bin_attr_init(&queue->bin);
+
+		/* Queue name index starts from 1 */
+		queue->bin.attr.name =
+			devm_kasprintf(dev, GFP_KERNEL, "bmc-dev-queue%d", (i + 1));
+		queue->bin.attr.mode = 0600;
+		queue->bin.read = bmc_device->platform->queue_rx;
+		queue->bin.write = bmc_device->platform->queue_tx;
+		queue->bin.size = 4;
+		queue->bin.private = queue;
+
+		ret = sysfs_create_bin_file(&pdev->dev.kobj, &queue->bin);
+		if (ret) {
+			dev_err(dev, "error for bin%d file\n", i);
+			return ret;
+		}
+
+		queue->kn = kernfs_find_and_get(dev->kobj.sd, queue->bin.attr.name);
+		if (!queue->kn) {
+			sysfs_remove_bin_file(&dev->kobj, &queue->bin);
+			return ret;
+		}
+
+		queue->index = i;
+		queue->bmc_device = bmc_device;
+	}
+
+	return 0;
+}
+
+static int aspeed_bmc_device_setup_memory_mapping(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	bmc_device->miscdev.minor = MISC_DYNAMIC_MINOR;
+	bmc_device->miscdev.name = devm_kasprintf(dev, GFP_KERNEL, "bmc-device%d", bmc_device->id);
+	bmc_device->miscdev.fops = &aspeed_bmc_device_fops;
+	bmc_device->miscdev.parent = dev;
+	ret = misc_register(&bmc_device->miscdev);
+	if (ret) {
+		dev_err(dev, "Unable to register device\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct aspeed_platform ast2600_plaform = {
+	.init = aspeed_ast2600_init,
+	.queue_rx = aspeed_ast2600_queue_rx,
+	.queue_tx = aspeed_ast2600_queue_tx
+};
+
+static struct aspeed_platform ast2700_plaform = {
+	.init = aspeed_ast2700_init,
+	.queue_rx = aspeed_ast2700_queue_rx,
+	.queue_tx = aspeed_ast2700_queue_tx
+};
+
+static const struct of_device_id aspeed_bmc_device_of_matches[] = {
+	{ .compatible = "aspeed,ast2600-bmc-device", .data = &ast2600_plaform },
+	{ .compatible = "aspeed,ast2700-bmc-device", .data = &ast2700_plaform },
+	{},
+};
+MODULE_DEVICE_TABLE(of, aspeed_bmc_device_of_matches);
+
+static int aspeed_bmc_device_probe(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device;
+	struct device *dev = &pdev->dev;
+	struct resource res;
+	const void *md = of_device_get_match_data(dev);
+	struct device_node *np;
+	int ret = 0, i;
+
+	if (!md)
+		return -ENODEV;
+
+	bmc_device = devm_kzalloc(&pdev->dev, sizeof(struct aspeed_bmc_device), GFP_KERNEL);
+	if (!bmc_device)
+		return -ENOMEM;
+	dev_set_drvdata(dev, bmc_device);
+
+	bmc_device->platform = md;
+
+	bmc_device->id = of_alias_get_id(dev->of_node, "bmcdev");
+	if (bmc_device->id < 0)
+		bmc_device->id = 0;
+
+	bmc_device->dev = dev;
+	bmc_device->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(bmc_device->reg_base))
+		return PTR_ERR(bmc_device->reg_base);
+
+	ret = of_reserved_mem_device_init(dev);
+	if (ret) {
+		dev_err(dev, "of_reserved_mem_device_init failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+	if (ret) {
+		dev_err(dev, "cannot set 64-bits DMA mask\n");
+		return ret;
+	}
+
+	np = of_parse_phandle(dev->of_node, "memory-region", 0);
+	if (!np || of_address_to_resource(np, 0, &res)) {
+		dev_err(dev, "Failed to find memory-region.\n");
+		return -ENOMEM;
+	}
+
+	of_node_put(np);
+
+	bmc_device->bmc_mem_size = resource_size(&res);
+	bmc_device->bmc_mem_cpu = dmam_alloc_coherent(dev, bmc_device->bmc_mem_size,
+						      &bmc_device->bmc_mem_phy, GFP_KERNEL);
+	if (!bmc_device->bmc_mem_cpu) {
+		dev_err(dev, "Failed to allocate BMC memory.\n");
+		return -ENOMEM;
+	}
+
+	bmc_device->irq = platform_get_irq(pdev, 0);
+	if (bmc_device->irq < 0) {
+		dev_err(&pdev->dev, "platform get of irq[=%d] failed!\n", bmc_device->irq);
+		return bmc_device->irq;
+	}
+
+	ret = devm_request_irq(&pdev->dev, bmc_device->irq, aspeed_bmc_dev_isr, 0,
+			       dev_name(&pdev->dev), bmc_device);
+	if (ret) {
+		dev_err(dev, "aspeed bmc device Unable to get IRQ");
+		return ret;
+	}
+
+	ret = aspeed_bmc_device_setup_queue(pdev);
+	if (ret) {
+		dev_err(dev, "Cannot setup queue message");
+		goto out;
+	}
+
+	ret = aspeed_bmc_device_setup_memory_mapping(pdev);
+	if (ret) {
+		dev_err(dev, "Cannot setup memory mapping misc");
+		goto out_free_queue;
+	}
+
+	if (of_property_read_bool(dev->of_node, "pcie2lpc"))
+		bmc_device->pcie2lpc = 1;
+
+	ret = bmc_device->platform->init(pdev);
+	if (ret) {
+		dev_err(dev, "Initialize bmc device failed\n");
+		goto out_free_misc;
+	}
+
+	bmc_device->pcie_irq =  platform_get_irq(pdev, 1);
+	if (bmc_device->pcie_irq < 0) {
+		dev_warn(&pdev->dev,
+			 "platform get of pcie irq[=%d] failed!\n", bmc_device->pcie_irq);
+	} else {
+		ret = devm_request_irq(&pdev->dev, bmc_device->pcie_irq,
+				       aspeed_bmc_dev_pcie_isr, IRQF_SHARED,
+				       dev_name(&pdev->dev), bmc_device);
+		if (ret < 0) {
+			dev_warn(dev, "Failed to request PCI-E IRQ %d.\n", ret);
+			bmc_device->pcie_irq = -1;
+		}
+	}
+
+	dev_info(dev, "aspeed bmc device: driver successfully loaded.\n");
+
+	return 0;
+
+out_free_misc:
+	misc_deregister(&bmc_device->miscdev);
+out_free_queue:
+	for (i = 0; i < ASPEED_QUEUE_NUM; i++)
+		sysfs_remove_bin_file(&pdev->dev.kobj, &bmc_device->queue[i].bin);
+out:
+	dev_warn(dev, "aspeed bmc device: driver init failed (ret=%d)!\n", ret);
+	return ret;
+}
+
+static void aspeed_bmc_device_remove(struct platform_device *pdev)
+{
+	struct aspeed_bmc_device *bmc_device = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < ASPEED_QUEUE_NUM; i++)
+		sysfs_remove_bin_file(&pdev->dev.kobj, &bmc_device->queue[i].bin);
+	misc_deregister(&bmc_device->miscdev);
+	devm_free_irq(&pdev->dev, bmc_device->irq, bmc_device);
+	devm_free_irq(&pdev->dev, bmc_device->pcie_irq, bmc_device);
+
+	devm_kfree(&pdev->dev, bmc_device);
+}
+
+static struct platform_driver aspeed_bmc_device_driver = {
+	.probe		= aspeed_bmc_device_probe,
+	.remove		= aspeed_bmc_device_remove,
+	.driver		= {
+		.name	= KBUILD_MODNAME,
+		.of_match_table = aspeed_bmc_device_of_matches,
+	},
+};
+
+module_platform_driver(aspeed_bmc_device_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED BMC DEVICE Driver");
+MODULE_LICENSE("GPL");