--- /dev/null
+/*
+ * Copyright 2017 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+
+#include <linux/aspeed-lpc-ctrl.h>
+
+#define DEVICE_NAME "aspeed-lpc-ctrl"
+
+#define HICR7 0x8
+#define HICR8 0xc
+
+struct aspeed_lpc_ctrl {
+ struct miscdevice miscdev;
+ struct regmap *regmap;
+ phys_addr_t mem_base;
+ resource_size_t mem_size;
+ u32 pnor_size;
+ u32 pnor_base;
+};
+
+static struct aspeed_lpc_ctrl *file_aspeed_lpc_ctrl(struct file *file)
+{
+ return container_of(file->private_data, struct aspeed_lpc_ctrl,
+ miscdev);
+}
+
+static int aspeed_lpc_ctrl_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
+ unsigned long vsize = vma->vm_end - vma->vm_start;
+ pgprot_t prot = vma->vm_page_prot;
+
+ if (vma->vm_pgoff + vsize > lpc_ctrl->mem_base + lpc_ctrl->mem_size)
+ return -EINVAL;
+
+ /* ast2400/2500 AHB accesses are not cache coherent */
+ prot = pgprot_dmacoherent(prot);
+
+ if (remap_pfn_range(vma, vma->vm_start,
+ (lpc_ctrl->mem_base >> PAGE_SHIFT) + vma->vm_pgoff,
+ vsize, prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
+ unsigned long param)
+{
+ struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
+ void __user *p = (void __user *)param;
+ struct aspeed_lpc_ctrl_mapping map;
+ u32 addr;
+ u32 size;
+ long rc;
+
+ if (copy_from_user(&map, p, sizeof(map)))
+ return -EFAULT;
+
+ if (map.flags != 0)
+ return -EINVAL;
+
+ switch (cmd) {
+ case ASPEED_LPC_CTRL_IOCTL_GET_SIZE:
+ /* The flash windows don't report their size */
+ if (map.window_type != ASPEED_LPC_CTRL_WINDOW_MEMORY)
+ return -EINVAL;
+
+ /* Support more than one window id in the future */
+ if (map.window_id != 0)
+ return -EINVAL;
+
+ map.size = lpc_ctrl->mem_size;
+
+ return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0;
+ case ASPEED_LPC_CTRL_IOCTL_MAP:
+
+ /*
+ * The top half of HICR7 is the MSB of the BMC address of the
+ * mapping.
+ * The bottom half of HICR7 is the MSB of the HOST LPC
+ * firmware space address of the mapping.
+ *
+ * The 1 bits in the top of half of HICR8 represent the bits
+ * (in the requested address) that should be ignored and
+ * replaced with those from the top half of HICR7.
+ * The 1 bits in the bottom half of HICR8 represent the bits
+ * (in the requested address) that should be kept and pass
+ * into the BMC address space.
+ */
+
+ /*
+ * It doesn't make sense to talk about a size or offset with
+ * low 16 bits set. Both HICR7 and HICR8 talk about the top 16
+ * bits of addresses and sizes.
+ */
+
+ if ((map.size & 0x0000ffff) || (map.offset & 0x0000ffff))
+ return -EINVAL;
+
+ /*
+ * Because of the way the masks work in HICR8 offset has to
+ * be a multiple of size.
+ */
+ if (map.offset & (map.size - 1))
+ return -EINVAL;
+
+ if (map.window_type == ASPEED_LPC_CTRL_WINDOW_FLASH) {
+ addr = lpc_ctrl->pnor_base;
+ size = lpc_ctrl->pnor_size;
+ } else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) {
+ addr = lpc_ctrl->mem_base;
+ size = lpc_ctrl->mem_size;
+ } else {
+ return -EINVAL;
+ }
+
+ /* Check overflow first! */
+ if (map.offset + map.size < map.offset ||
+ map.offset + map.size > size)
+ return -EINVAL;
+
+ if (map.size == 0 || map.size > size)
+ return -EINVAL;
+
+ addr += map.offset;
+
+ /*
+ * addr (host lpc address) is safe regardless of values. This
+ * simply changes the address the host has to request on its
+ * side of the LPC bus. This cannot impact the hosts own
+ * memory space by surprise as LPC specific accessors are
+ * required. The only strange thing that could be done is
+ * setting the lower 16 bits but the shift takes care of that.
+ */
+
+ rc = regmap_write(lpc_ctrl->regmap, HICR7,
+ (addr | (map.addr >> 16)));
+ if (rc)
+ return rc;
+
+ return regmap_write(lpc_ctrl->regmap, HICR8,
+ (~(map.size - 1)) | ((map.size >> 16) - 1));
+ }
+
+ return -EINVAL;
+}
+
+static const struct file_operations aspeed_lpc_ctrl_fops = {
+ .owner = THIS_MODULE,
+ .mmap = aspeed_lpc_ctrl_mmap,
+ .unlocked_ioctl = aspeed_lpc_ctrl_ioctl,
+};
+
+static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
+{
+ struct aspeed_lpc_ctrl *lpc_ctrl;
+ struct device_node *node;
+ struct resource resm;
+ struct device *dev;
+ int rc;
+
+ dev = &pdev->dev;
+
+ lpc_ctrl = devm_kzalloc(dev, sizeof(*lpc_ctrl), GFP_KERNEL);
+ if (!lpc_ctrl)
+ return -ENOMEM;
+
+ node = of_parse_phandle(dev->of_node, "flash", 0);
+ if (!node) {
+ dev_err(dev, "Didn't find host pnor flash node\n");
+ return -ENODEV;
+ }
+
+ rc = of_address_to_resource(node, 1, &resm);
+ of_node_put(node);
+ if (rc) {
+ dev_err(dev, "Couldn't address to resource for flash\n");
+ return rc;
+ }
+
+ lpc_ctrl->pnor_size = resource_size(&resm);
+ lpc_ctrl->pnor_base = resm.start;
+
+ dev_set_drvdata(&pdev->dev, lpc_ctrl);
+
+ node = of_parse_phandle(dev->of_node, "memory-region", 0);
+ if (!node) {
+ dev_err(dev, "Didn't find reserved memory\n");
+ return -EINVAL;
+ }
+
+ rc = of_address_to_resource(node, 0, &resm);
+ of_node_put(node);
+ if (rc) {
+ dev_err(dev, "Couldn't address to resource for reserved memory\n");
+ return -ENOMEM;
+ }
+
+ lpc_ctrl->mem_size = resource_size(&resm);
+ lpc_ctrl->mem_base = resm.start;
+
+ lpc_ctrl->regmap = syscon_node_to_regmap(
+ pdev->dev.parent->of_node);
+ if (IS_ERR(lpc_ctrl->regmap)) {
+ dev_err(dev, "Couldn't get regmap\n");
+ return -ENODEV;
+ }
+
+ lpc_ctrl->miscdev.minor = MISC_DYNAMIC_MINOR;
+ lpc_ctrl->miscdev.name = DEVICE_NAME;
+ lpc_ctrl->miscdev.fops = &aspeed_lpc_ctrl_fops;
+ lpc_ctrl->miscdev.parent = dev;
+ rc = misc_register(&lpc_ctrl->miscdev);
+ if (rc)
+ dev_err(dev, "Unable to register device\n");
+ else
+ dev_info(dev, "Loaded at 0x%08x (0x%08x)\n",
+ lpc_ctrl->mem_base, lpc_ctrl->mem_size);
+
+ return rc;
+}
+
+static int aspeed_lpc_ctrl_remove(struct platform_device *pdev)
+{
+ struct aspeed_lpc_ctrl *lpc_ctrl = dev_get_drvdata(&pdev->dev);
+
+ misc_deregister(&lpc_ctrl->miscdev);
+
+ return 0;
+}
+
+static const struct of_device_id aspeed_lpc_ctrl_match[] = {
+ { .compatible = "aspeed,ast2400-lpc-ctrl" },
+ { .compatible = "aspeed,ast2500-lpc-ctrl" },
+ { },
+};
+
+static struct platform_driver aspeed_lpc_ctrl_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = aspeed_lpc_ctrl_match,
+ },
+ .probe = aspeed_lpc_ctrl_probe,
+ .remove = aspeed_lpc_ctrl_remove,
+};
+
+module_platform_driver(aspeed_lpc_ctrl_driver);
+
+MODULE_DEVICE_TABLE(of, aspeed_lpc_ctrl_match);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Cyril Bur <cyrilbur@gmail.com>");
+MODULE_DESCRIPTION("Control for aspeed 2400/2500 LPC HOST to BMC mappings");
--- /dev/null
+/*
+ * Copyright 2017 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_ASPEED_LPC_CTRL_H
+#define _UAPI_LINUX_ASPEED_LPC_CTRL_H
+
+#include <linux/ioctl.h>
+
+/* Window types */
+#define ASPEED_LPC_CTRL_WINDOW_FLASH 1
+#define ASPEED_LPC_CTRL_WINDOW_MEMORY 2
+
+/*
+ * This driver provides a window for the host to access a BMC resource
+ * across the BMC <-> Host LPC bus.
+ *
+ * window_type: The BMC resource that the host will access through the
+ * window. BMC flash and BMC RAM.
+ *
+ * window_id: For each window type there may be multiple windows,
+ * these are referenced by ID.
+ *
+ * flags: Reserved for future use, this field is expected to be
+ * zeroed.
+ *
+ * addr: Address on the host LPC bus that the specified window should
+ * be mapped. This address must be power of two aligned.
+ *
+ * offset: Offset into the BMC window that should be mapped to the
+ * host (at addr). This must be a multiple of size.
+ *
+ * size: The size of the mapping. The smallest possible size is 64K.
+ * This must be power of two aligned.
+ *
+ */
+
+struct aspeed_lpc_ctrl_mapping {
+ __u8 window_type;
+ __u8 window_id;
+ __u16 flags;
+ __u32 addr;
+ __u32 offset;
+ __u32 size;
+};
+
+#define __ASPEED_LPC_CTRL_IOCTL_MAGIC 0xb2
+
+#define ASPEED_LPC_CTRL_IOCTL_GET_SIZE _IOWR(__ASPEED_LPC_CTRL_IOCTL_MAGIC, \
+ 0x00, struct aspeed_lpc_ctrl_mapping)
+
+#define ASPEED_LPC_CTRL_IOCTL_MAP _IOW(__ASPEED_LPC_CTRL_IOCTL_MAGIC, \
+ 0x01, struct aspeed_lpc_ctrl_mapping)
+
+#endif /* _UAPI_LINUX_ASPEED_LPC_CTRL_H */
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commitdiff