diff options
| -rw-r--r-- | drivers/misc/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/misc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/misc/aspeed-lpc-ctrl.c | 267 | ||||
| -rw-r--r-- | include/uapi/linux/aspeed-lpc-ctrl.h | 60 |
4 files changed, 336 insertions, 0 deletions
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index c290990d73ed..77b001e7cf85 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -771,6 +771,14 @@ config PANEL_BOOT_MESSAGE endif # PANEL +config ASPEED_LPC_CTRL + depends on (ARCH_ASPEED || COMPILE_TEST) && REGMAP && MFD_SYSCON + tristate "Aspeed ast2400/2500 HOST LPC to BMC bridge control" + ---help--- + Control Aspeed ast2400/2500 HOST LPC to BMC mappings through + ioctl()s, the driver also provides a read/write interface to a BMC ram + region where the host LPC read/write region can be buffered. + source "drivers/misc/c2port/Kconfig" source "drivers/misc/eeprom/Kconfig" source "drivers/misc/cb710/Kconfig" diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 7a3ea89339b4..4925ea8e1952 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -54,6 +54,7 @@ obj-$(CONFIG_ECHO) += echo/ obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o obj-$(CONFIG_CXL_BASE) += cxl/ obj-$(CONFIG_PANEL) += panel.o +obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o lkdtm-$(CONFIG_LKDTM) += lkdtm_core.o lkdtm-$(CONFIG_LKDTM) += lkdtm_bugs.o diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c new file mode 100644 index 000000000000..f6acbe1d9378 --- /dev/null +++ b/drivers/misc/aspeed-lpc-ctrl.c @@ -0,0 +1,267 @@ +/* + * 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"); diff --git a/include/uapi/linux/aspeed-lpc-ctrl.h b/include/uapi/linux/aspeed-lpc-ctrl.h new file mode 100644 index 000000000000..f96fa995a3f0 --- /dev/null +++ b/include/uapi/linux/aspeed-lpc-ctrl.h @@ -0,0 +1,60 @@ +/* + * 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 */ |