diff options
Diffstat (limited to 'drivers/soc/aspeed')
| -rw-r--r-- | drivers/soc/aspeed/Kconfig | 32 | ||||
| -rw-r--r-- | drivers/soc/aspeed/Makefile | 4 | ||||
| -rw-r--r-- | drivers/soc/aspeed/aspeed-lpc-ctrl.c | 310 | ||||
| -rw-r--r-- | drivers/soc/aspeed/aspeed-lpc-snoop.c | 371 | ||||
| -rw-r--r-- | drivers/soc/aspeed/aspeed-p2a-ctrl.c | 444 |
5 files changed, 1161 insertions, 0 deletions
diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig new file mode 100644 index 000000000..c95fa30f1 --- /dev/null +++ b/drivers/soc/aspeed/Kconfig @@ -0,0 +1,32 @@ +# SPDX-License-Identifier: GPL-2.0-only +menu "Aspeed SoC drivers" + +config SOC_ASPEED + def_bool y + depends on ARCH_ASPEED || COMPILE_TEST + +config ASPEED_LPC_CTRL + depends on SOC_ASPEED && 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. + +config ASPEED_LPC_SNOOP + tristate "Aspeed ast2500 HOST LPC snoop support" + depends on SOC_ASPEED && REGMAP && MFD_SYSCON + help + Provides a driver to control the LPC snoop interface which + allows the BMC to listen on and save the data written by + the host to an arbitrary LPC I/O port. + +config ASPEED_P2A_CTRL + depends on SOC_ASPEED && REGMAP && MFD_SYSCON + tristate "Aspeed ast2400/2500 HOST P2A VGA MMIO to BMC bridge control" + help + Control Aspeed ast2400/2500 HOST P2A VGA MMIO to BMC mappings through + ioctl()s, the driver also provides an interface for userspace mappings to + a pre-defined region. + +endmenu diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile new file mode 100644 index 000000000..b64be47f2 --- /dev/null +++ b/drivers/soc/aspeed/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o +obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o +obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o diff --git a/drivers/soc/aspeed/aspeed-lpc-ctrl.c b/drivers/soc/aspeed/aspeed-lpc-ctrl.c new file mode 100644 index 000000000..71b555c71 --- /dev/null +++ b/drivers/soc/aspeed/aspeed-lpc-ctrl.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2017 IBM Corporation + */ + +#include <linux/clk.h> +#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 HICR5 0x0 +#define HICR5_ENL2H BIT(8) +#define HICR5_ENFWH BIT(10) + +#define HICR7 0x8 +#define HICR8 0xc + +struct aspeed_lpc_ctrl { + struct miscdevice miscdev; + struct regmap *regmap; + struct clk *clk; + 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 + vma_pages(vma) > lpc_ctrl->mem_size >> PAGE_SHIFT) + return -EINVAL; + + /* ast2400/2500 AHB accesses are not cache coherent */ + prot = pgprot_noncached(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); + struct device *dev = file->private_data; + 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; + + /* If memory-region is not described in device tree */ + if (!lpc_ctrl->mem_size) { + dev_dbg(dev, "Didn't find reserved memory\n"); + return -ENXIO; + } + + 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) { + if (!lpc_ctrl->pnor_size) { + dev_dbg(dev, "Didn't find host pnor flash\n"); + return -ENXIO; + } + addr = lpc_ctrl->pnor_base; + size = lpc_ctrl->pnor_size; + } else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) { + /* If memory-region is not described in device tree */ + if (!lpc_ctrl->mem_size) { + dev_dbg(dev, "Didn't find reserved memory\n"); + return -ENXIO; + } + 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; + + rc = regmap_write(lpc_ctrl->regmap, HICR8, + (~(map.size - 1)) | ((map.size >> 16) - 1)); + if (rc) + return rc; + + /* + * Enable LPC FHW cycles. This is required for the host to + * access the regions specified. + */ + return regmap_update_bits(lpc_ctrl->regmap, HICR5, + HICR5_ENFWH | HICR5_ENL2H, + HICR5_ENFWH | HICR5_ENL2H); + } + + 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; + + /* If flash is described in device tree then store */ + node = of_parse_phandle(dev->of_node, "flash", 0); + if (!node) { + dev_dbg(dev, "Didn't find host pnor flash node\n"); + } else { + 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); + + /* If memory-region is described in device tree then store */ + node = of_parse_phandle(dev->of_node, "memory-region", 0); + if (!node) { + dev_dbg(dev, "Didn't find reserved memory\n"); + } else { + 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 -ENXIO; + } + + 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->clk = devm_clk_get(dev, NULL); + if (IS_ERR(lpc_ctrl->clk)) + return dev_err_probe(dev, PTR_ERR(lpc_ctrl->clk), + "couldn't get clock\n"); + rc = clk_prepare_enable(lpc_ctrl->clk); + if (rc) { + dev_err(dev, "couldn't enable clock\n"); + return rc; + } + + 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"); + goto err; + } + + return 0; + +err: + clk_disable_unprepare(lpc_ctrl->clk); + 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); + clk_disable_unprepare(lpc_ctrl->clk); + + 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/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c new file mode 100644 index 000000000..538d7aab8 --- /dev/null +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c @@ -0,0 +1,371 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2017 Google Inc + * + * Provides a simple driver to control the ASPEED LPC snoop interface which + * allows the BMC to listen on and save the data written by + * the host to an arbitrary LPC I/O port. + * + * Typically used by the BMC to "watch" host boot progress via port + * 0x80 writes made by the BIOS during the boot process. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/fs.h> +#include <linux/kfifo.h> +#include <linux/mfd/syscon.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/poll.h> +#include <linux/regmap.h> + +#define DEVICE_NAME "aspeed-lpc-snoop" + +#define NUM_SNOOP_CHANNELS 2 +#define SNOOP_FIFO_SIZE 2048 + +#define HICR5 0x0 +#define HICR5_EN_SNP0W BIT(0) +#define HICR5_ENINT_SNP0W BIT(1) +#define HICR5_EN_SNP1W BIT(2) +#define HICR5_ENINT_SNP1W BIT(3) + +#define HICR6 0x4 +#define HICR6_STR_SNP0W BIT(0) +#define HICR6_STR_SNP1W BIT(1) +#define SNPWADR 0x10 +#define SNPWADR_CH0_MASK GENMASK(15, 0) +#define SNPWADR_CH0_SHIFT 0 +#define SNPWADR_CH1_MASK GENMASK(31, 16) +#define SNPWADR_CH1_SHIFT 16 +#define SNPWDR 0x14 +#define SNPWDR_CH0_MASK GENMASK(7, 0) +#define SNPWDR_CH0_SHIFT 0 +#define SNPWDR_CH1_MASK GENMASK(15, 8) +#define SNPWDR_CH1_SHIFT 8 +#define HICRB 0x80 +#define HICRB_ENSNP0D BIT(14) +#define HICRB_ENSNP1D BIT(15) + +struct aspeed_lpc_snoop_model_data { + /* The ast2400 has bits 14 and 15 as reserved, whereas the ast2500 + * can use them. + */ + unsigned int has_hicrb_ensnp; +}; + +struct aspeed_lpc_snoop_channel { + struct kfifo fifo; + wait_queue_head_t wq; + struct miscdevice miscdev; +}; + +struct aspeed_lpc_snoop { + struct regmap *regmap; + int irq; + struct clk *clk; + struct aspeed_lpc_snoop_channel chan[NUM_SNOOP_CHANNELS]; +}; + +static struct aspeed_lpc_snoop_channel *snoop_file_to_chan(struct file *file) +{ + return container_of(file->private_data, + struct aspeed_lpc_snoop_channel, + miscdev); +} + +static ssize_t snoop_file_read(struct file *file, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct aspeed_lpc_snoop_channel *chan = snoop_file_to_chan(file); + unsigned int copied; + int ret = 0; + + if (kfifo_is_empty(&chan->fifo)) { + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + ret = wait_event_interruptible(chan->wq, + !kfifo_is_empty(&chan->fifo)); + if (ret == -ERESTARTSYS) + return -EINTR; + } + ret = kfifo_to_user(&chan->fifo, buffer, count, &copied); + if (ret) + return ret; + + return copied; +} + +static __poll_t snoop_file_poll(struct file *file, + struct poll_table_struct *pt) +{ + struct aspeed_lpc_snoop_channel *chan = snoop_file_to_chan(file); + + poll_wait(file, &chan->wq, pt); + return !kfifo_is_empty(&chan->fifo) ? EPOLLIN : 0; +} + +static const struct file_operations snoop_fops = { + .owner = THIS_MODULE, + .read = snoop_file_read, + .poll = snoop_file_poll, + .llseek = noop_llseek, +}; + +/* Save a byte to a FIFO and discard the oldest byte if FIFO is full */ +static void put_fifo_with_discard(struct aspeed_lpc_snoop_channel *chan, u8 val) +{ + if (!kfifo_initialized(&chan->fifo)) + return; + if (kfifo_is_full(&chan->fifo)) + kfifo_skip(&chan->fifo); + kfifo_put(&chan->fifo, val); + wake_up_interruptible(&chan->wq); +} + +static irqreturn_t aspeed_lpc_snoop_irq(int irq, void *arg) +{ + struct aspeed_lpc_snoop *lpc_snoop = arg; + u32 reg, data; + + if (regmap_read(lpc_snoop->regmap, HICR6, ®)) + return IRQ_NONE; + + /* Check if one of the snoop channels is interrupting */ + reg &= (HICR6_STR_SNP0W | HICR6_STR_SNP1W); + if (!reg) + return IRQ_NONE; + + /* Ack pending IRQs */ + regmap_write(lpc_snoop->regmap, HICR6, reg); + + /* Read and save most recent snoop'ed data byte to FIFO */ + regmap_read(lpc_snoop->regmap, SNPWDR, &data); + + if (reg & HICR6_STR_SNP0W) { + u8 val = (data & SNPWDR_CH0_MASK) >> SNPWDR_CH0_SHIFT; + + put_fifo_with_discard(&lpc_snoop->chan[0], val); + } + if (reg & HICR6_STR_SNP1W) { + u8 val = (data & SNPWDR_CH1_MASK) >> SNPWDR_CH1_SHIFT; + + put_fifo_with_discard(&lpc_snoop->chan[1], val); + } + + return IRQ_HANDLED; +} + +static int aspeed_lpc_snoop_config_irq(struct aspeed_lpc_snoop *lpc_snoop, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int rc; + + lpc_snoop->irq = platform_get_irq(pdev, 0); + if (!lpc_snoop->irq) + return -ENODEV; + + rc = devm_request_irq(dev, lpc_snoop->irq, + aspeed_lpc_snoop_irq, IRQF_SHARED, + DEVICE_NAME, lpc_snoop); + if (rc < 0) { + dev_warn(dev, "Unable to request IRQ %d\n", lpc_snoop->irq); + lpc_snoop->irq = 0; + return rc; + } + + return 0; +} + +static int aspeed_lpc_enable_snoop(struct aspeed_lpc_snoop *lpc_snoop, + struct device *dev, + int channel, u16 lpc_port) +{ + int rc = 0; + u32 hicr5_en, snpwadr_mask, snpwadr_shift, hicrb_en; + const struct aspeed_lpc_snoop_model_data *model_data = + of_device_get_match_data(dev); + + init_waitqueue_head(&lpc_snoop->chan[channel].wq); + /* Create FIFO datastructure */ + rc = kfifo_alloc(&lpc_snoop->chan[channel].fifo, + SNOOP_FIFO_SIZE, GFP_KERNEL); + if (rc) + return rc; + + lpc_snoop->chan[channel].miscdev.minor = MISC_DYNAMIC_MINOR; + lpc_snoop->chan[channel].miscdev.name = + devm_kasprintf(dev, GFP_KERNEL, "%s%d", DEVICE_NAME, channel); + lpc_snoop->chan[channel].miscdev.fops = &snoop_fops; + lpc_snoop->chan[channel].miscdev.parent = dev; + rc = misc_register(&lpc_snoop->chan[channel].miscdev); + if (rc) + return rc; + + /* Enable LPC snoop channel at requested port */ + switch (channel) { + case 0: + hicr5_en = HICR5_EN_SNP0W | HICR5_ENINT_SNP0W; + snpwadr_mask = SNPWADR_CH0_MASK; + snpwadr_shift = SNPWADR_CH0_SHIFT; + hicrb_en = HICRB_ENSNP0D; + break; + case 1: + hicr5_en = HICR5_EN_SNP1W | HICR5_ENINT_SNP1W; + snpwadr_mask = SNPWADR_CH1_MASK; + snpwadr_shift = SNPWADR_CH1_SHIFT; + hicrb_en = HICRB_ENSNP1D; + break; + default: + return -EINVAL; + } + + regmap_update_bits(lpc_snoop->regmap, HICR5, hicr5_en, hicr5_en); + regmap_update_bits(lpc_snoop->regmap, SNPWADR, snpwadr_mask, + lpc_port << snpwadr_shift); + if (model_data->has_hicrb_ensnp) + regmap_update_bits(lpc_snoop->regmap, HICRB, + hicrb_en, hicrb_en); + + return rc; +} + +static void aspeed_lpc_disable_snoop(struct aspeed_lpc_snoop *lpc_snoop, + int channel) +{ + switch (channel) { + case 0: + regmap_update_bits(lpc_snoop->regmap, HICR5, + HICR5_EN_SNP0W | HICR5_ENINT_SNP0W, + 0); + break; + case 1: + regmap_update_bits(lpc_snoop->regmap, HICR5, + HICR5_EN_SNP1W | HICR5_ENINT_SNP1W, + 0); + break; + default: + return; + } + + kfifo_free(&lpc_snoop->chan[channel].fifo); + misc_deregister(&lpc_snoop->chan[channel].miscdev); +} + +static int aspeed_lpc_snoop_probe(struct platform_device *pdev) +{ + struct aspeed_lpc_snoop *lpc_snoop; + struct device *dev; + u32 port; + int rc; + + dev = &pdev->dev; + + lpc_snoop = devm_kzalloc(dev, sizeof(*lpc_snoop), GFP_KERNEL); + if (!lpc_snoop) + return -ENOMEM; + + lpc_snoop->regmap = syscon_node_to_regmap( + pdev->dev.parent->of_node); + if (IS_ERR(lpc_snoop->regmap)) { + dev_err(dev, "Couldn't get regmap\n"); + return -ENODEV; + } + + dev_set_drvdata(&pdev->dev, lpc_snoop); + + rc = of_property_read_u32_index(dev->of_node, "snoop-ports", 0, &port); + if (rc) { + dev_err(dev, "no snoop ports configured\n"); + return -ENODEV; + } + + lpc_snoop->clk = devm_clk_get(dev, NULL); + if (IS_ERR(lpc_snoop->clk)) { + rc = PTR_ERR(lpc_snoop->clk); + if (rc != -EPROBE_DEFER) + dev_err(dev, "couldn't get clock\n"); + return rc; + } + rc = clk_prepare_enable(lpc_snoop->clk); + if (rc) { + dev_err(dev, "couldn't enable clock\n"); + return rc; + } + + rc = aspeed_lpc_snoop_config_irq(lpc_snoop, pdev); + if (rc) + goto err; + + rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 0, port); + if (rc) + goto err; + + /* Configuration of 2nd snoop channel port is optional */ + if (of_property_read_u32_index(dev->of_node, "snoop-ports", + 1, &port) == 0) { + rc = aspeed_lpc_enable_snoop(lpc_snoop, dev, 1, port); + if (rc) { + aspeed_lpc_disable_snoop(lpc_snoop, 0); + goto err; + } + } + + return 0; + +err: + clk_disable_unprepare(lpc_snoop->clk); + + return rc; +} + +static int aspeed_lpc_snoop_remove(struct platform_device *pdev) +{ + struct aspeed_lpc_snoop *lpc_snoop = dev_get_drvdata(&pdev->dev); + + /* Disable both snoop channels */ + aspeed_lpc_disable_snoop(lpc_snoop, 0); + aspeed_lpc_disable_snoop(lpc_snoop, 1); + + clk_disable_unprepare(lpc_snoop->clk); + + return 0; +} + +static const struct aspeed_lpc_snoop_model_data ast2400_model_data = { + .has_hicrb_ensnp = 0, +}; + +static const struct aspeed_lpc_snoop_model_data ast2500_model_data = { + .has_hicrb_ensnp = 1, +}; + +static const struct of_device_id aspeed_lpc_snoop_match[] = { + { .compatible = "aspeed,ast2400-lpc-snoop", + .data = &ast2400_model_data }, + { .compatible = "aspeed,ast2500-lpc-snoop", + .data = &ast2500_model_data }, + { }, +}; + +static struct platform_driver aspeed_lpc_snoop_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = aspeed_lpc_snoop_match, + }, + .probe = aspeed_lpc_snoop_probe, + .remove = aspeed_lpc_snoop_remove, +}; + +module_platform_driver(aspeed_lpc_snoop_driver); + +MODULE_DEVICE_TABLE(of, aspeed_lpc_snoop_match); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Robert Lippert <rlippert@google.com>"); +MODULE_DESCRIPTION("Linux driver to control Aspeed LPC snoop functionality"); diff --git a/drivers/soc/aspeed/aspeed-p2a-ctrl.c b/drivers/soc/aspeed/aspeed-p2a-ctrl.c new file mode 100644 index 000000000..20b5fb2a2 --- /dev/null +++ b/drivers/soc/aspeed/aspeed-p2a-ctrl.c @@ -0,0 +1,444 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2019 Google Inc + * + * 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. + * + * Provides a simple driver to control the ASPEED P2A interface which allows + * the host to read and write to various regions of the BMC's memory. + */ + +#include <linux/fs.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/miscdevice.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +#include <linux/aspeed-p2a-ctrl.h> + +#define DEVICE_NAME "aspeed-p2a-ctrl" + +/* SCU2C is a Misc. Control Register. */ +#define SCU2C 0x2c +/* SCU180 is the PCIe Configuration Setting Control Register. */ +#define SCU180 0x180 +/* Bit 1 controls the P2A bridge, while bit 0 controls the entire VGA device + * on the PCI bus. + */ +#define SCU180_ENP2A BIT(1) + +/* The ast2400/2500 both have six ranges. */ +#define P2A_REGION_COUNT 6 + +struct region { + u64 min; + u64 max; + u32 bit; +}; + +struct aspeed_p2a_model_data { + /* min, max, bit */ + struct region regions[P2A_REGION_COUNT]; +}; + +struct aspeed_p2a_ctrl { + struct miscdevice miscdev; + struct regmap *regmap; + + const struct aspeed_p2a_model_data *config; + + /* Access to these needs to be locked, held via probe, mapping ioctl, + * and release, remove. + */ + struct mutex tracking; + u32 readers; + u32 readerwriters[P2A_REGION_COUNT]; + + phys_addr_t mem_base; + resource_size_t mem_size; +}; + +struct aspeed_p2a_user { + struct file *file; + struct aspeed_p2a_ctrl *parent; + + /* The entire memory space is opened for reading once the bridge is + * enabled, therefore this needs only to be tracked once per user. + * If any user has it open for read, the bridge must stay enabled. + */ + u32 read; + + /* Each entry of the array corresponds to a P2A Region. If the user + * opens for read or readwrite, the reference goes up here. On + * release, this array is walked and references adjusted accordingly. + */ + u32 readwrite[P2A_REGION_COUNT]; +}; + +static void aspeed_p2a_enable_bridge(struct aspeed_p2a_ctrl *p2a_ctrl) +{ + regmap_update_bits(p2a_ctrl->regmap, + SCU180, SCU180_ENP2A, SCU180_ENP2A); +} + +static void aspeed_p2a_disable_bridge(struct aspeed_p2a_ctrl *p2a_ctrl) +{ + regmap_update_bits(p2a_ctrl->regmap, SCU180, SCU180_ENP2A, 0); +} + +static int aspeed_p2a_mmap(struct file *file, struct vm_area_struct *vma) +{ + unsigned long vsize; + pgprot_t prot; + struct aspeed_p2a_user *priv = file->private_data; + struct aspeed_p2a_ctrl *ctrl = priv->parent; + + if (ctrl->mem_base == 0 && ctrl->mem_size == 0) + return -EINVAL; + + vsize = vma->vm_end - vma->vm_start; + prot = vma->vm_page_prot; + + if (vma->vm_pgoff + vma_pages(vma) > ctrl->mem_size >> PAGE_SHIFT) + return -EINVAL; + + /* ast2400/2500 AHB accesses are not cache coherent */ + prot = pgprot_noncached(prot); + + if (remap_pfn_range(vma, vma->vm_start, + (ctrl->mem_base >> PAGE_SHIFT) + vma->vm_pgoff, + vsize, prot)) + return -EAGAIN; + + return 0; +} + +static bool aspeed_p2a_region_acquire(struct aspeed_p2a_user *priv, + struct aspeed_p2a_ctrl *ctrl, + struct aspeed_p2a_ctrl_mapping *map) +{ + int i; + u64 base, end; + bool matched = false; + + base = map->addr; + end = map->addr + (map->length - 1); + + /* If the value is a legal u32, it will find a match. */ + for (i = 0; i < P2A_REGION_COUNT; i++) { + const struct region *curr = &ctrl->config->regions[i]; + + /* If the top of this region is lower than your base, skip it. + */ + if (curr->max < base) + continue; + + /* If the bottom of this region is higher than your end, bail. + */ + if (curr->min > end) + break; + + /* Lock this and update it, therefore it someone else is + * closing their file out, this'll preserve the increment. + */ + mutex_lock(&ctrl->tracking); + ctrl->readerwriters[i] += 1; + mutex_unlock(&ctrl->tracking); + + /* Track with the user, so when they close their file, we can + * decrement properly. + */ + priv->readwrite[i] += 1; + + /* Enable the region as read-write. */ + regmap_update_bits(ctrl->regmap, SCU2C, curr->bit, 0); + matched = true; + } + + return matched; +} + +static long aspeed_p2a_ioctl(struct file *file, unsigned int cmd, + unsigned long data) +{ + struct aspeed_p2a_user *priv = file->private_data; + struct aspeed_p2a_ctrl *ctrl = priv->parent; + void __user *arg = (void __user *)data; + struct aspeed_p2a_ctrl_mapping map; + + if (copy_from_user(&map, arg, sizeof(map))) + return -EFAULT; + + switch (cmd) { + case ASPEED_P2A_CTRL_IOCTL_SET_WINDOW: + /* If they want a region to be read-only, since the entire + * region is read-only once enabled, we just need to track this + * user wants to read from the bridge, and if it's not enabled. + * Enable it. + */ + if (map.flags == ASPEED_P2A_CTRL_READ_ONLY) { + mutex_lock(&ctrl->tracking); + ctrl->readers += 1; + mutex_unlock(&ctrl->tracking); + + /* Track with the user, so when they close their file, + * we can decrement properly. + */ + priv->read += 1; + } else if (map.flags == ASPEED_P2A_CTRL_READWRITE) { + /* If we don't acquire any region return error. */ + if (!aspeed_p2a_region_acquire(priv, ctrl, &map)) { + return -EINVAL; + } + } else { + /* Invalid map flags. */ + return -EINVAL; + } + + aspeed_p2a_enable_bridge(ctrl); + return 0; + case ASPEED_P2A_CTRL_IOCTL_GET_MEMORY_CONFIG: + /* This is a request for the memory-region and corresponding + * length that is used by the driver for mmap. + */ + + map.flags = 0; + map.addr = ctrl->mem_base; + map.length = ctrl->mem_size; + + return copy_to_user(arg, &map, sizeof(map)) ? -EFAULT : 0; + } + + return -EINVAL; +} + + +/* + * When a user opens this file, we create a structure to track their mappings. + * + * A user can map a region as read-only (bridge enabled), or read-write (bit + * flipped, and bridge enabled). Either way, this tracking is used, s.t. when + * they release the device references are handled. + * + * The bridge is not enabled until a user calls an ioctl to map a region, + * simply opening the device does not enable it. + */ +static int aspeed_p2a_open(struct inode *inode, struct file *file) +{ + struct aspeed_p2a_user *priv; + + priv = kmalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->file = file; + priv->read = 0; + memset(priv->readwrite, 0, sizeof(priv->readwrite)); + + /* The file's private_data is initialized to the p2a_ctrl. */ + priv->parent = file->private_data; + + /* Set the file's private_data to the user's data. */ + file->private_data = priv; + + return 0; +} + +/* + * This will close the users mappings. It will go through what they had opened + * for readwrite, and decrement those counts. If at the end, this is the last + * user, it'll close the bridge. + */ +static int aspeed_p2a_release(struct inode *inode, struct file *file) +{ + int i; + u32 bits = 0; + bool open_regions = false; + struct aspeed_p2a_user *priv = file->private_data; + + /* Lock others from changing these values until everything is updated + * in one pass. + */ + mutex_lock(&priv->parent->tracking); + + priv->parent->readers -= priv->read; + + for (i = 0; i < P2A_REGION_COUNT; i++) { + priv->parent->readerwriters[i] -= priv->readwrite[i]; + + if (priv->parent->readerwriters[i] > 0) + open_regions = true; + else + bits |= priv->parent->config->regions[i].bit; + } + + /* Setting a bit to 1 disables the region, so let's just OR with the + * above to disable any. + */ + + /* Note, if another user is trying to ioctl, they can't grab tracking, + * and therefore can't grab either register mutex. + * If another user is trying to close, they can't grab tracking either. + */ + regmap_update_bits(priv->parent->regmap, SCU2C, bits, bits); + + /* If parent->readers is zero and open windows is 0, disable the + * bridge. + */ + if (!open_regions && priv->parent->readers == 0) + aspeed_p2a_disable_bridge(priv->parent); + + mutex_unlock(&priv->parent->tracking); + + kfree(priv); + + return 0; +} + +static const struct file_operations aspeed_p2a_ctrl_fops = { + .owner = THIS_MODULE, + .mmap = aspeed_p2a_mmap, + .unlocked_ioctl = aspeed_p2a_ioctl, + .open = aspeed_p2a_open, + .release = aspeed_p2a_release, +}; + +/* The regions are controlled by SCU2C */ +static void aspeed_p2a_disable_all(struct aspeed_p2a_ctrl *p2a_ctrl) +{ + int i; + u32 value = 0; + + for (i = 0; i < P2A_REGION_COUNT; i++) + value |= p2a_ctrl->config->regions[i].bit; + + regmap_update_bits(p2a_ctrl->regmap, SCU2C, value, value); + + /* Disable the bridge. */ + aspeed_p2a_disable_bridge(p2a_ctrl); +} + +static int aspeed_p2a_ctrl_probe(struct platform_device *pdev) +{ + struct aspeed_p2a_ctrl *misc_ctrl; + struct device *dev; + struct resource resm; + struct device_node *node; + int rc = 0; + + dev = &pdev->dev; + + misc_ctrl = devm_kzalloc(dev, sizeof(*misc_ctrl), GFP_KERNEL); + if (!misc_ctrl) + return -ENOMEM; + + mutex_init(&misc_ctrl->tracking); + + /* optional. */ + node = of_parse_phandle(dev->of_node, "memory-region", 0); + if (node) { + 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 -ENODEV; + } + + misc_ctrl->mem_size = resource_size(&resm); + misc_ctrl->mem_base = resm.start; + } + + misc_ctrl->regmap = syscon_node_to_regmap(pdev->dev.parent->of_node); + if (IS_ERR(misc_ctrl->regmap)) { + dev_err(dev, "Couldn't get regmap\n"); + return -ENODEV; + } + + misc_ctrl->config = of_device_get_match_data(dev); + + dev_set_drvdata(&pdev->dev, misc_ctrl); + + aspeed_p2a_disable_all(misc_ctrl); + + misc_ctrl->miscdev.minor = MISC_DYNAMIC_MINOR; + misc_ctrl->miscdev.name = DEVICE_NAME; + misc_ctrl->miscdev.fops = &aspeed_p2a_ctrl_fops; + misc_ctrl->miscdev.parent = dev; + + rc = misc_register(&misc_ctrl->miscdev); + if (rc) + dev_err(dev, "Unable to register device\n"); + + return rc; +} + +static int aspeed_p2a_ctrl_remove(struct platform_device *pdev) +{ + struct aspeed_p2a_ctrl *p2a_ctrl = dev_get_drvdata(&pdev->dev); + + misc_deregister(&p2a_ctrl->miscdev); + + return 0; +} + +#define SCU2C_DRAM BIT(25) +#define SCU2C_SPI BIT(24) +#define SCU2C_SOC BIT(23) +#define SCU2C_FLASH BIT(22) + +static const struct aspeed_p2a_model_data ast2400_model_data = { + .regions = { + {0x00000000, 0x17FFFFFF, SCU2C_FLASH}, + {0x18000000, 0x1FFFFFFF, SCU2C_SOC}, + {0x20000000, 0x2FFFFFFF, SCU2C_FLASH}, + {0x30000000, 0x3FFFFFFF, SCU2C_SPI}, + {0x40000000, 0x5FFFFFFF, SCU2C_DRAM}, + {0x60000000, 0xFFFFFFFF, SCU2C_SOC}, + } +}; + +static const struct aspeed_p2a_model_data ast2500_model_data = { + .regions = { + {0x00000000, 0x0FFFFFFF, SCU2C_FLASH}, + {0x10000000, 0x1FFFFFFF, SCU2C_SOC}, + {0x20000000, 0x3FFFFFFF, SCU2C_FLASH}, + {0x40000000, 0x5FFFFFFF, SCU2C_SOC}, + {0x60000000, 0x7FFFFFFF, SCU2C_SPI}, + {0x80000000, 0xFFFFFFFF, SCU2C_DRAM}, + } +}; + +static const struct of_device_id aspeed_p2a_ctrl_match[] = { + { .compatible = "aspeed,ast2400-p2a-ctrl", + .data = &ast2400_model_data }, + { .compatible = "aspeed,ast2500-p2a-ctrl", + .data = &ast2500_model_data }, + { }, +}; + +static struct platform_driver aspeed_p2a_ctrl_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = aspeed_p2a_ctrl_match, + }, + .probe = aspeed_p2a_ctrl_probe, + .remove = aspeed_p2a_ctrl_remove, +}; + +module_platform_driver(aspeed_p2a_ctrl_driver); + +MODULE_DEVICE_TABLE(of, aspeed_p2a_ctrl_match); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Patrick Venture <venture@google.com>"); +MODULE_DESCRIPTION("Control for aspeed 2400/2500 P2A VGA HOST to BMC mappings"); |