diff options
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/Kconfig | 30 | ||||
| -rw-r--r-- | drivers/misc/Makefile | 4 | ||||
| -rw-r--r-- | drivers/misc/aspeed-lpc-ctrl.c | 58 | ||||
| -rw-r--r-- | drivers/misc/aspeed-lpc-mbox.c | 334 | ||||
| -rw-r--r-- | drivers/misc/aspeed-p2a-ctrl.c | 444 | ||||
| -rw-r--r-- | drivers/misc/npcm7xx-lpc-bpc.c | 394 | ||||
| -rw-r--r-- | drivers/misc/npcm7xx-pci-mbox.c | 288 |
7 files changed, 1530 insertions, 22 deletions
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index f417b06e11c5..31361d7046cb 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -485,6 +485,14 @@ config VEXPRESS_SYSCFG bus. System Configuration interface is one of the possible means of generating transactions on this bus. +config ASPEED_P2A_CTRL + depends on (ARCH_ASPEED || COMPILE_TEST) && 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. + config ASPEED_LPC_CTRL depends on (ARCH_ASPEED || COMPILE_TEST) && REGMAP && MFD_SYSCON tristate "Aspeed ast2400/2500 HOST LPC to BMC bridge control" @@ -501,6 +509,13 @@ config ASPEED_LPC_SNOOP allows the BMC to listen on and save the data written by the host to an arbitrary LPC I/O port. +config ASPEED_LPC_MBOX + tristate "Aspeed LPC Mailbox Controller" + depends on (ARCH_ASPEED || COMPILE_TEST) && REGMAP && MFD_SYSCON + ---help--- + Expose the ASPEED LPC MBOX registers found on Aspeed SOCs (AST2400 + and AST2500) to userspace. + config PCI_ENDPOINT_TEST depends on PCI select CRC32 @@ -521,6 +536,21 @@ config PVPANIC a paravirtualized device provided by QEMU; it lets a virtual machine (guest) communicate panic events to the host. +config NPCM7XX_LPC_BPC + tristate "NPCM7xx LPC BIOS Post Code support" + depends on (ARCH_NPCM7XX || COMPILE_TEST) + help + Provides a NPCM7xx driver to control the LPC BIOS Post Code + interface which allows the BMC to monitoring and save + the data written by the host to an arbitrary LPC I/O port. + +config NPCM7XX_PCI_MBOX + tristate "NPCM7xx PCI Mailbox Controller" + depends on (ARCH_NPCM7XX || COMPILE_TEST) && REGMAP && MFD_SYSCON + help + Expose the NPCM750/730/715/705 PCI MBOX registers found on + Nuvoton SOCs to userspace. + 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 e39ccbbc1b3a..d0c495886720 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -55,7 +55,11 @@ obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o obj-$(CONFIG_CXL_BASE) += cxl/ obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o +obj-$(CONFIG_ASPEED_LPC_MBOX) += aspeed-lpc-mbox.o +obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o obj-$(CONFIG_PCI_ENDPOINT_TEST) += pci_endpoint_test.o obj-$(CONFIG_OCXL) += ocxl/ obj-y += cardreader/ obj-$(CONFIG_PVPANIC) += pvpanic.o +obj-$(CONFIG_NPCM7XX_LPC_BPC) += npcm7xx-lpc-bpc.o +obj-$(CONFIG_NPCM7XX_PCI_MBOX) += npcm7xx-pci-mbox.o diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c index a024f8042259..332210e06e98 100644 --- a/drivers/misc/aspeed-lpc-ctrl.c +++ b/drivers/misc/aspeed-lpc-ctrl.c @@ -68,6 +68,7 @@ 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; @@ -90,6 +91,12 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd, if (map.window_id != 0) return -EINVAL; + /* If memory-region is not described in device tree */ + if (!lpc_ctrl->mem_size) { + dev_err(dev, "Didn't find reserved memory\n"); + return -EINVAL; + } + map.size = lpc_ctrl->mem_size; return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0; @@ -126,9 +133,18 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd, return -EINVAL; if (map.window_type == ASPEED_LPC_CTRL_WINDOW_FLASH) { + if (!lpc_ctrl->pnor_size) { + dev_err(dev, "Didn't find host pnor flash\n"); + return -EINVAL; + } 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_err(dev, "Didn't find reserved memory\n"); + return -EINVAL; + } addr = lpc_ctrl->mem_base; size = lpc_ctrl->mem_size; } else { @@ -196,17 +212,17 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev) 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_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; + 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); @@ -214,22 +230,22 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev) 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_err(dev, "Didn't find reserved memory\n"); - return -EINVAL; - } + 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 -ENOMEM; + } - 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->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)) { @@ -258,8 +274,6 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev) goto err; } - dev_info(dev, "Loaded at %pr\n", &resm); - return 0; err: diff --git a/drivers/misc/aspeed-lpc-mbox.c b/drivers/misc/aspeed-lpc-mbox.c new file mode 100644 index 000000000000..bab86e5e2943 --- /dev/null +++ b/drivers/misc/aspeed-lpc-mbox.c @@ -0,0 +1,334 @@ +/* + * 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/interrupt.h> +#include <linux/mfd/syscon.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/poll.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define DEVICE_NAME "aspeed-mbox" + +#define ASPEED_MBOX_NUM_REGS 16 + +#define ASPEED_MBOX_DATA_0 0x00 +#define ASPEED_MBOX_STATUS_0 0x40 +#define ASPEED_MBOX_STATUS_1 0x44 +#define ASPEED_MBOX_BMC_CTRL 0x48 +#define ASPEED_MBOX_CTRL_RECV BIT(7) +#define ASPEED_MBOX_CTRL_MASK BIT(1) +#define ASPEED_MBOX_CTRL_SEND BIT(0) +#define ASPEED_MBOX_HOST_CTRL 0x4c +#define ASPEED_MBOX_INTERRUPT_0 0x50 +#define ASPEED_MBOX_INTERRUPT_1 0x54 + +struct aspeed_mbox { + struct miscdevice miscdev; + struct regmap *regmap; + unsigned int base; + wait_queue_head_t queue; + struct mutex mutex; +}; + +static atomic_t aspeed_mbox_open_count = ATOMIC_INIT(0); + +static u8 aspeed_mbox_inb(struct aspeed_mbox *mbox, int reg) +{ + /* + * The mbox registers are actually only one byte but are addressed + * four bytes apart. The other three bytes are marked 'reserved', + * they *should* be zero but lets not rely on it. + * I am going to rely on the fact we can casually read/write to them... + */ + unsigned int val = 0xff; /* If regmap throws an error return 0xff */ + int rc = regmap_read(mbox->regmap, mbox->base + reg, &val); + + if (rc) + dev_err(mbox->miscdev.parent, "regmap_read() failed with " + "%d (reg: 0x%08x)\n", rc, reg); + + return val & 0xff; +} + +static void aspeed_mbox_outb(struct aspeed_mbox *mbox, u8 data, int reg) +{ + int rc = regmap_write(mbox->regmap, mbox->base + reg, data); + + if (rc) + dev_err(mbox->miscdev.parent, "regmap_write() failed with " + "%d (data: %u reg: 0x%08x)\n", rc, data, reg); +} + +static struct aspeed_mbox *file_mbox(struct file *file) +{ + return container_of(file->private_data, struct aspeed_mbox, miscdev); +} + +static int aspeed_mbox_open(struct inode *inode, struct file *file) +{ + struct aspeed_mbox *mbox = file_mbox(file); + + if (atomic_inc_return(&aspeed_mbox_open_count) == 1) { + /* + * Clear the interrupt status bit if it was left on and unmask + * interrupts. + * ASPEED_MBOX_CTRL_RECV bit is W1C, this also unmasks in 1 step + */ + aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_RECV, ASPEED_MBOX_BMC_CTRL); + return 0; + } + + atomic_dec(&aspeed_mbox_open_count); + return -EBUSY; +} + +static ssize_t aspeed_mbox_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct aspeed_mbox *mbox = file_mbox(file); + char __user *p = buf; + ssize_t ret; + int i; + + if (!access_ok(buf, count)) + return -EFAULT; + + if (count + *ppos > ASPEED_MBOX_NUM_REGS) + return -EINVAL; + + if (file->f_flags & O_NONBLOCK) { + if (!(aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & + ASPEED_MBOX_CTRL_RECV)) + return -EAGAIN; + } else if (wait_event_interruptible(mbox->queue, + aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & + ASPEED_MBOX_CTRL_RECV)) { + return -ERESTARTSYS; + } + + mutex_lock(&mbox->mutex); + + for (i = *ppos; count > 0 && i < ASPEED_MBOX_NUM_REGS; i++) { + uint8_t reg = aspeed_mbox_inb(mbox, ASPEED_MBOX_DATA_0 + (i * 4)); + + ret = __put_user(reg, p); + if (ret) + goto out_unlock; + + p++; + count--; + } + + /* ASPEED_MBOX_CTRL_RECV bit is write to clear, this also unmasks in 1 step */ + aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_RECV, ASPEED_MBOX_BMC_CTRL); + ret = p - buf; + +out_unlock: + mutex_unlock(&mbox->mutex); + return ret; +} + +static ssize_t aspeed_mbox_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct aspeed_mbox *mbox = file_mbox(file); + const char __user *p = buf; + ssize_t ret; + char c; + int i; + + if (!access_ok(buf, count)) + return -EFAULT; + + if (count + *ppos > ASPEED_MBOX_NUM_REGS) + return -EINVAL; + + mutex_lock(&mbox->mutex); + + for (i = *ppos; count > 0 && i < ASPEED_MBOX_NUM_REGS; i++) { + ret = __get_user(c, p); + if (ret) + goto out_unlock; + + aspeed_mbox_outb(mbox, c, ASPEED_MBOX_DATA_0 + (i * 4)); + p++; + count--; + } + + aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_SEND, ASPEED_MBOX_BMC_CTRL); + ret = p - buf; + +out_unlock: + mutex_unlock(&mbox->mutex); + return ret; +} + +static unsigned int aspeed_mbox_poll(struct file *file, poll_table *wait) +{ + struct aspeed_mbox *mbox = file_mbox(file); + unsigned int mask = 0; + + poll_wait(file, &mbox->queue, wait); + + if (aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & ASPEED_MBOX_CTRL_RECV) + mask |= POLLIN; + + return mask; +} + +static int aspeed_mbox_release(struct inode *inode, struct file *file) +{ + atomic_dec(&aspeed_mbox_open_count); + return 0; +} + +static const struct file_operations aspeed_mbox_fops = { + .owner = THIS_MODULE, + .llseek = no_seek_end_llseek, + .read = aspeed_mbox_read, + .write = aspeed_mbox_write, + .open = aspeed_mbox_open, + .release = aspeed_mbox_release, + .poll = aspeed_mbox_poll, +}; + +static irqreturn_t aspeed_mbox_irq(int irq, void *arg) +{ + struct aspeed_mbox *mbox = arg; + + if (!(aspeed_mbox_inb(mbox, ASPEED_MBOX_BMC_CTRL) & ASPEED_MBOX_CTRL_RECV)) + return IRQ_NONE; + + /* + * Leave the status bit set so that we know the data is for us, + * clear it once it has been read. + */ + + /* Mask it off, we'll clear it when we the data gets read */ + aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_MASK, ASPEED_MBOX_BMC_CTRL); + + wake_up(&mbox->queue); + return IRQ_HANDLED; +} + +static int aspeed_mbox_config_irq(struct aspeed_mbox *mbox, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int rc, irq; + + irq = irq_of_parse_and_map(dev->of_node, 0); + if (!irq) + return -ENODEV; + + rc = devm_request_irq(dev, irq, aspeed_mbox_irq, + IRQF_SHARED, DEVICE_NAME, mbox); + if (rc < 0) { + dev_err(dev, "Unable to request IRQ %d\n", irq); + return rc; + } + + /* + * Disable all register based interrupts. + */ + aspeed_mbox_outb(mbox, 0x00, ASPEED_MBOX_INTERRUPT_0); /* regs 0 - 7 */ + aspeed_mbox_outb(mbox, 0x00, ASPEED_MBOX_INTERRUPT_1); /* regs 8 - 15 */ + + /* These registers are write one to clear. Clear them. */ + aspeed_mbox_outb(mbox, 0xff, ASPEED_MBOX_STATUS_0); + aspeed_mbox_outb(mbox, 0xff, ASPEED_MBOX_STATUS_1); + + aspeed_mbox_outb(mbox, ASPEED_MBOX_CTRL_RECV, ASPEED_MBOX_BMC_CTRL); + return 0; +} + +static int aspeed_mbox_probe(struct platform_device *pdev) +{ + struct aspeed_mbox *mbox; + struct device *dev; + int rc; + + dev = &pdev->dev; + + mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + dev_set_drvdata(&pdev->dev, mbox); + + rc = of_property_read_u32(dev->of_node, "reg", &mbox->base); + if (rc) { + dev_err(dev, "Couldn't read reg device-tree property\n"); + return rc; + } + + mbox->regmap = syscon_node_to_regmap( + pdev->dev.parent->of_node); + if (IS_ERR(mbox->regmap)) { + dev_err(dev, "Couldn't get regmap\n"); + return -ENODEV; + } + + mutex_init(&mbox->mutex); + init_waitqueue_head(&mbox->queue); + + mbox->miscdev.minor = MISC_DYNAMIC_MINOR; + mbox->miscdev.name = DEVICE_NAME; + mbox->miscdev.fops = &aspeed_mbox_fops; + mbox->miscdev.parent = dev; + rc = misc_register(&mbox->miscdev); + if (rc) { + dev_err(dev, "Unable to register device\n"); + return rc; + } + + rc = aspeed_mbox_config_irq(mbox, pdev); + if (rc) { + dev_err(dev, "Failed to configure IRQ\n"); + misc_deregister(&mbox->miscdev); + return rc; + } + + return 0; +} + +static int aspeed_mbox_remove(struct platform_device *pdev) +{ + struct aspeed_mbox *mbox = dev_get_drvdata(&pdev->dev); + + misc_deregister(&mbox->miscdev); + + return 0; +} + +static const struct of_device_id aspeed_mbox_match[] = { + { .compatible = "aspeed,ast2400-mbox" }, + { .compatible = "aspeed,ast2500-mbox" }, + { }, +}; + +static struct platform_driver aspeed_mbox_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = aspeed_mbox_match, + }, + .probe = aspeed_mbox_probe, + .remove = aspeed_mbox_remove, +}; + +module_platform_driver(aspeed_mbox_driver); + +MODULE_DEVICE_TABLE(of, aspeed_mbox_match); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Cyril Bur <cyrilbur@gmail.com>"); +MODULE_DESCRIPTION("Aspeed mailbox device driver"); diff --git a/drivers/misc/aspeed-p2a-ctrl.c b/drivers/misc/aspeed-p2a-ctrl.c new file mode 100644 index 000000000000..b60fbeaffcbd --- /dev/null +++ b/drivers/misc/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 + vsize > ctrl->mem_base + ctrl->mem_size) + 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"); diff --git a/drivers/misc/npcm7xx-lpc-bpc.c b/drivers/misc/npcm7xx-lpc-bpc.c new file mode 100644 index 000000000000..e014e07cd4a4 --- /dev/null +++ b/drivers/misc/npcm7xx-lpc-bpc.c @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2014-2018 Nuvoton Technology corporation. + +#include <linux/fs.h> +#include <linux/bitops.h> +#include <linux/interrupt.h> +#include <linux/kfifo.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/miscdevice.h> +#include <linux/poll.h> + +#define DEVICE_NAME "npcm7xx-lpc-bpc" + +#define NUM_BPC_CHANNELS 2 +#define DW_PAD_SIZE 3 + +/* BIOS POST Code FIFO Registers */ +#define NPCM7XX_BPCFA2L_REG 0x2 //BIOS POST Code FIFO Address 2 LSB +#define NPCM7XX_BPCFA2M_REG 0x4 //BIOS POST Code FIFO Address 2 MSB +#define NPCM7XX_BPCFEN_REG 0x6 //BIOS POST Code FIFO Enable +#define NPCM7XX_BPCFSTAT_REG 0x8 //BIOS POST Code FIFO Status +#define NPCM7XX_BPCFDATA_REG 0xA //BIOS POST Code FIFO Data +#define NPCM7XX_BPCFMSTAT_REG 0xC //BIOS POST Code FIFO Miscellaneous Status +#define NPCM7XX_BPCFA1L_REG 0x10 //BIOS POST Code FIFO Address 1 LSB +#define NPCM7XX_BPCFA1M_REG 0x12 //BIOS POST Code FIFO Address 1 MSB + +/*BIOS regiser data*/ +#define FIFO_IOADDR1_ENABLE 0x80 +#define FIFO_IOADDR2_ENABLE 0x40 + +/* BPC interface package and structure definition */ +#define BPC_KFIFO_SIZE 0x400 + +/*BPC regiser data*/ +#define FIFO_DATA_VALID 0x80 +#define FIFO_OVERFLOW 0x20 +#define FIFO_READY_INT_ENABLE 0x8 +#define FIFO_DWCAPTURE 0x4 +#define FIFO_ADDR_DECODE 0x1 + +/*Host Reset*/ +#define HOST_RESET_INT_ENABLE 0x10 +#define HOST_RESET_CHANGED 0x40 + +struct npcm7xx_bpc_channel { + struct npcm7xx_bpc *data; + struct kfifo fifo; + wait_queue_head_t wq; + bool host_reset; + struct miscdevice miscdev; +}; + +struct npcm7xx_bpc { + void __iomem *base; + int irq; + bool en_dwcap; + struct npcm7xx_bpc_channel ch[NUM_BPC_CHANNELS]; +}; + +static struct npcm7xx_bpc_channel *npcm7xx_file_to_ch(struct file *file) +{ + return container_of(file->private_data, struct npcm7xx_bpc_channel, + miscdev); +} + +static ssize_t npcm7xx_bpc_read(struct file *file, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct npcm7xx_bpc_channel *chan = npcm7xx_file_to_ch(file); + struct npcm7xx_bpc *lpc_bpc = chan->data; + unsigned int copied; + int ret = 0; + int cond_size = 1; + + if (lpc_bpc->en_dwcap) + cond_size = 3; + + if (kfifo_len(&chan->fifo) < cond_size) { + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible + (chan->wq, kfifo_len(&chan->fifo) > cond_size); + if (ret == -ERESTARTSYS) + return -EINTR; + } + + ret = kfifo_to_user(&chan->fifo, buffer, count, &copied); + + return ret ? ret : copied; +} + +static __poll_t npcm7xx_bpc_poll(struct file *file, + struct poll_table_struct *pt) +{ + struct npcm7xx_bpc_channel *chan = npcm7xx_file_to_ch(file); + __poll_t mask = 0; + + poll_wait(file, &chan->wq, pt); + if (!kfifo_is_empty(&chan->fifo)) + mask |= POLLIN; + + if (chan->host_reset) { + mask |= POLLHUP; + chan->host_reset = false; + } + + return mask; +} + +static const struct file_operations npcm7xx_bpc_fops = { + .owner = THIS_MODULE, + .read = npcm7xx_bpc_read, + .poll = npcm7xx_bpc_poll, + .llseek = noop_llseek, +}; + +static irqreturn_t npcm7xx_bpc_irq(int irq, void *arg) +{ + struct npcm7xx_bpc *lpc_bpc = arg; + u8 fifo_st; + u8 host_st; + u8 addr_index = 0; + u8 Data; + u8 padzero[3] = {0}; + u8 last_addr_bit = 0; + bool isr_flag = false; + + fifo_st = ioread8(lpc_bpc->base + NPCM7XX_BPCFSTAT_REG); + while (FIFO_DATA_VALID & fifo_st) { + /* If dwcapture enabled only channel 0 (FIFO 0) used */ + if (!lpc_bpc->en_dwcap) + addr_index = fifo_st & FIFO_ADDR_DECODE; + else + last_addr_bit = fifo_st & FIFO_ADDR_DECODE; + + /*Read data from FIFO to clear interrupt*/ + Data = ioread8(lpc_bpc->base + NPCM7XX_BPCFDATA_REG); + if (kfifo_is_full(&lpc_bpc->ch[addr_index].fifo)) + kfifo_skip(&lpc_bpc->ch[addr_index].fifo); + kfifo_put(&lpc_bpc->ch[addr_index].fifo, Data); + if (fifo_st & FIFO_OVERFLOW) + pr_info("BIOS Post Codes FIFO Overflow!!!\n"); + + fifo_st = ioread8(lpc_bpc->base + NPCM7XX_BPCFSTAT_REG); + if (lpc_bpc->en_dwcap && last_addr_bit) { + if ((fifo_st & FIFO_ADDR_DECODE) || + ((FIFO_DATA_VALID & fifo_st) == 0)) { + while (kfifo_avail(&lpc_bpc->ch[addr_index].fifo) < DW_PAD_SIZE) + kfifo_skip(&lpc_bpc->ch[addr_index].fifo); + kfifo_in(&lpc_bpc->ch[addr_index].fifo, + padzero, DW_PAD_SIZE); + } + } + isr_flag = true; + } + + host_st = ioread8(lpc_bpc->base + NPCM7XX_BPCFMSTAT_REG); + if (host_st & HOST_RESET_CHANGED) { + iowrite8(HOST_RESET_CHANGED, + lpc_bpc->base + NPCM7XX_BPCFMSTAT_REG); + lpc_bpc->ch[addr_index].host_reset = true; + isr_flag = true; + } + + if (isr_flag) { + wake_up_interruptible(&lpc_bpc->ch[addr_index].wq); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int npcm7xx_bpc_config_irq(struct npcm7xx_bpc *lpc_bpc, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int rc; + + lpc_bpc->irq = platform_get_irq(pdev, 0); + if (lpc_bpc->irq < 0) { + dev_err(dev, "get IRQ failed\n"); + return lpc_bpc->irq; + } + + rc = devm_request_irq(dev, lpc_bpc->irq, + npcm7xx_bpc_irq, IRQF_SHARED, + DEVICE_NAME, lpc_bpc); + if (rc < 0) { + dev_warn(dev, "Unable to request IRQ %d\n", lpc_bpc->irq); + return rc; + } + + return 0; +} + +static int npcm7xx_enable_bpc(struct npcm7xx_bpc *lpc_bpc, struct device *dev, + int channel, u16 lpc_port) +{ + int rc; + u8 addr_en, reg_en; + + init_waitqueue_head(&lpc_bpc->ch[channel].wq); + + rc = kfifo_alloc(&lpc_bpc->ch[channel].fifo, + BPC_KFIFO_SIZE, GFP_KERNEL); + if (rc) + return rc; + + lpc_bpc->ch[channel].miscdev.minor = MISC_DYNAMIC_MINOR; + lpc_bpc->ch[channel].miscdev.name = + devm_kasprintf(dev, GFP_KERNEL, "%s%d", DEVICE_NAME, channel); + lpc_bpc->ch[channel].miscdev.fops = &npcm7xx_bpc_fops; + lpc_bpc->ch[channel].miscdev.parent = dev; + rc = misc_register(&lpc_bpc->ch[channel].miscdev); + if (rc) + return rc; + + lpc_bpc->ch[channel].data = lpc_bpc; + lpc_bpc->ch[channel].host_reset = false; + + /* Enable LPC snoop channel at requested port */ + switch (channel) { + case 0: + addr_en = FIFO_IOADDR1_ENABLE; + iowrite8((u8)lpc_port & 0xFF, + lpc_bpc->base + NPCM7XX_BPCFA1L_REG); + iowrite8((u8)(lpc_port >> 8), + lpc_bpc->base + NPCM7XX_BPCFA1M_REG); + break; + case 1: + addr_en = FIFO_IOADDR2_ENABLE; + iowrite8((u8)lpc_port & 0xFF, + lpc_bpc->base + NPCM7XX_BPCFA2L_REG); + iowrite8((u8)(lpc_port >> 8), + lpc_bpc->base + NPCM7XX_BPCFA2M_REG); + break; + default: + return -EINVAL; + } + + if (lpc_bpc->en_dwcap) + addr_en = FIFO_DWCAPTURE; + + /* + * Enable FIFO Ready Interrupt, FIFO Capture of I/O addr, + * and Host Reset + */ + reg_en = ioread8(lpc_bpc->base + NPCM7XX_BPCFEN_REG); + iowrite8(reg_en | addr_en | FIFO_READY_INT_ENABLE | + HOST_RESET_INT_ENABLE, lpc_bpc->base + NPCM7XX_BPCFEN_REG); + + return 0; +} + +static void npcm7xx_disable_bpc(struct npcm7xx_bpc *lpc_bpc, int channel) +{ + u8 reg_en; + + switch (channel) { + case 0: + reg_en = ioread8(lpc_bpc->base + NPCM7XX_BPCFEN_REG); + if (lpc_bpc->en_dwcap) + iowrite8(reg_en & ~FIFO_DWCAPTURE, + lpc_bpc->base + NPCM7XX_BPCFEN_REG); + else + iowrite8(reg_en & ~FIFO_IOADDR1_ENABLE, + lpc_bpc->base + NPCM7XX_BPCFEN_REG); + break; + case 1: + reg_en = ioread8(lpc_bpc->base + NPCM7XX_BPCFEN_REG); + iowrite8(reg_en & ~FIFO_IOADDR2_ENABLE, + lpc_bpc->base + NPCM7XX_BPCFEN_REG); + break; + default: + return; + } + + if (!(reg_en & (FIFO_IOADDR1_ENABLE | FIFO_IOADDR2_ENABLE))) + iowrite8(reg_en & + ~(FIFO_READY_INT_ENABLE | HOST_RESET_INT_ENABLE), + lpc_bpc->base + NPCM7XX_BPCFEN_REG); + + kfifo_free(&lpc_bpc->ch[channel].fifo); + misc_deregister(&lpc_bpc->ch[channel].miscdev); +} + +static int npcm7xx_bpc_probe(struct platform_device *pdev) +{ + struct npcm7xx_bpc *lpc_bpc; + struct resource *res; + struct device *dev; + u32 port; + int rc; + + dev = &pdev->dev; + + lpc_bpc = devm_kzalloc(dev, sizeof(*lpc_bpc), GFP_KERNEL); + if (!lpc_bpc) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "BIOS post code reg resource not found\n"); + return -ENODEV; + } + + dev_dbg(dev, "BIOS post code base resource is %pR\n", res); + lpc_bpc->base = devm_ioremap_resource(dev, res); + if (IS_ERR(lpc_bpc->base)) + return PTR_ERR(lpc_bpc->base); + + dev_set_drvdata(&pdev->dev, lpc_bpc); + + rc = of_property_read_u32_index(dev->of_node, "monitor-ports", 0, + &port); + if (rc) { + dev_err(dev, "no monitor ports configured\n"); + return -ENODEV; + } + + lpc_bpc->en_dwcap = + of_property_read_bool(dev->of_node, "bpc-en-dwcapture"); + + rc = npcm7xx_bpc_config_irq(lpc_bpc, pdev); + if (rc) + return rc; + + rc = npcm7xx_enable_bpc(lpc_bpc, dev, 0, port); + if (rc) { + dev_err(dev, "Enable BIOS post code I/O port 0 failed\n"); + return rc; + } + + /* + * Configuration of second BPC channel port is optional + * Double-Word Capture ignoring address 2 + */ + if (!lpc_bpc->en_dwcap) { + if (of_property_read_u32_index(dev->of_node, "monitor-ports", + 1, &port) == 0) { + rc = npcm7xx_enable_bpc(lpc_bpc, dev, 1, port); + if (rc) { + dev_err(dev, "Enable BIOS post code I/O port 1 failed, disable I/O port 0\n"); + npcm7xx_disable_bpc(lpc_bpc, 0); + return rc; + } + } + } + + pr_info("npcm7xx BIOS post code probe\n"); + + return rc; +} + +static int npcm7xx_bpc_remove(struct platform_device *pdev) +{ + struct npcm7xx_bpc *lpc_bpc = dev_get_drvdata(&pdev->dev); + u8 reg_en; + + reg_en = ioread8(lpc_bpc->base + NPCM7XX_BPCFEN_REG); + + if (reg_en & FIFO_IOADDR1_ENABLE) + npcm7xx_disable_bpc(lpc_bpc, 0); + if (reg_en & FIFO_IOADDR2_ENABLE) + npcm7xx_disable_bpc(lpc_bpc, 1); + + return 0; +} + +static const struct of_device_id npcm7xx_bpc_match[] = { + { .compatible = "nuvoton,npcm750-lpc-bpc" }, + { }, +}; + +static struct platform_driver npcm7xx_bpc_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = npcm7xx_bpc_match, + }, + .probe = npcm7xx_bpc_probe, + .remove = npcm7xx_bpc_remove, +}; + +module_platform_driver(npcm7xx_bpc_driver); + +MODULE_DEVICE_TABLE(of, npcm7xx_bpc_match); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomer Maimon <tomer.maimon@nuvoton.com>"); +MODULE_DESCRIPTION("Linux driver to control NPCM7XX LPC BIOS post code monitoring"); diff --git a/drivers/misc/npcm7xx-pci-mbox.c b/drivers/misc/npcm7xx-pci-mbox.c new file mode 100644 index 000000000000..1a80661a4296 --- /dev/null +++ b/drivers/misc/npcm7xx-pci-mbox.c @@ -0,0 +1,288 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2014-2018 Nuvoton Technology corporation. + +#include <linux/interrupt.h> +#include <linux/mfd/syscon.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/poll.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define DEVICE_NAME "npcm7xx-pci-mbox" + +#define NPCM7XX_MBOX_BMBXSTAT 0x0 +#define NPCM7XX_MBOX_BMBXCTL 0x4 +#define NPCM7XX_MBOX_BMBXCMD 0x8 + +#define NPCM7XX_MBOX_CIF_0 BIT(0) +#define NPCM7XX_MBOX_CIE_0 BIT(0) +#define NPCM7XX_MBOX_HIF_0 BIT(0) + +#define NPCM7XX_MBOX_ALL_CIF GENMASK(7, 0) +#define NPCM7XX_MBOX_ALL_CIE GENMASK(7, 0) +#define NPCM7XX_MBOX_ALL_HIF GENMASK(7, 0) + +struct npcm7xx_mbox { + struct miscdevice miscdev; + struct regmap *regmap; + void __iomem *memory; + wait_queue_head_t queue; + spinlock_t lock; /* mbox access mutex */ + bool cif0; + u32 max_buf_size; +}; + +static atomic_t npcm7xx_mbox_open_count = ATOMIC_INIT(0); + +static struct npcm7xx_mbox *file_mbox(struct file *file) +{ + return container_of(file->private_data, struct npcm7xx_mbox, miscdev); +} + +static int npcm7xx_mbox_open(struct inode *inode, struct file *file) +{ + struct npcm7xx_mbox *mbox = file_mbox(file); + + if (atomic_inc_return(&npcm7xx_mbox_open_count) == 1) { + /* enable mailbox interrupt */ + regmap_update_bits(mbox->regmap, NPCM7XX_MBOX_BMBXCTL, + NPCM7XX_MBOX_ALL_CIE, NPCM7XX_MBOX_CIE_0); + return 0; + } + + atomic_dec(&npcm7xx_mbox_open_count); + return -EBUSY; +} + +static ssize_t npcm7xx_mbox_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct npcm7xx_mbox *mbox = file_mbox(file); + unsigned long flags; + + if (!access_ok(buf, count)) + return -EFAULT; + + if ((*ppos + count) > mbox->max_buf_size) + return -EINVAL; + + if (file->f_flags & O_NONBLOCK) { + if (!mbox->cif0) + return -EAGAIN; + } else if (wait_event_interruptible(mbox->queue, mbox->cif0)) { + return -ERESTARTSYS; + } + + spin_lock_irqsave(&mbox->lock, flags); + + if (copy_to_user((void __user *)buf, + (const void *)(mbox->memory + *ppos), count)) { + spin_unlock_irqrestore(&mbox->lock, flags); + return -EFAULT; + } + + mbox->cif0 = false; + spin_unlock_irqrestore(&mbox->lock, flags); + return count; +} + +static ssize_t npcm7xx_mbox_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct npcm7xx_mbox *mbox = file_mbox(file); + unsigned long flags; + + if (!access_ok(buf, count)) + return -EFAULT; + + if ((*ppos + count) > mbox->max_buf_size) + return -EINVAL; + + spin_lock_irqsave(&mbox->lock, flags); + + if (copy_from_user((void *)(mbox->memory + *ppos), + (void __user *)buf, count)) { + spin_unlock_irqrestore(&mbox->lock, flags); + return -EFAULT; + } + + regmap_update_bits(mbox->regmap, NPCM7XX_MBOX_BMBXCMD, + NPCM7XX_MBOX_ALL_HIF, NPCM7XX_MBOX_HIF_0); + + spin_unlock_irqrestore(&mbox->lock, flags); + return count; +} + +static unsigned int npcm7xx_mbox_poll(struct file *file, poll_table *wait) +{ + struct npcm7xx_mbox *mbox = file_mbox(file); + unsigned int mask = 0; + + poll_wait(file, &mbox->queue, wait); + if (mbox->cif0) + mask |= POLLIN; + + return mask; +} + +static int npcm7xx_mbox_release(struct inode *inode, struct file *file) +{ + atomic_dec(&npcm7xx_mbox_open_count); + return 0; +} + +static const struct file_operations npcm7xx_mbox_fops = { + .owner = THIS_MODULE, + .llseek = no_seek_end_llseek, + .read = npcm7xx_mbox_read, + .write = npcm7xx_mbox_write, + .open = npcm7xx_mbox_open, + .release = npcm7xx_mbox_release, + .poll = npcm7xx_mbox_poll, +}; + +static irqreturn_t npcm7xx_mbox_irq(int irq, void *arg) +{ + struct npcm7xx_mbox *mbox = arg; + u32 val; + + regmap_read(mbox->regmap, NPCM7XX_MBOX_BMBXSTAT, &val); + if ((val & NPCM7XX_MBOX_CIF_0) != NPCM7XX_MBOX_CIF_0) + return IRQ_NONE; + + /* + * Leave the status bit set so that we know the data is for us, + * clear it once it has been read. + */ + mbox->cif0 = true; + + /* Mask it off, we'll clear it when we the data gets read */ + regmap_write_bits(mbox->regmap, NPCM7XX_MBOX_BMBXSTAT, + NPCM7XX_MBOX_ALL_CIF, NPCM7XX_MBOX_CIF_0); + + wake_up(&mbox->queue); + + return IRQ_HANDLED; +} + +static int npcm7xx_mbox_config_irq(struct npcm7xx_mbox *mbox, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int rc, irq; + u32 val; + + /* Disable all register based interrupts */ + regmap_update_bits(mbox->regmap, NPCM7XX_MBOX_BMBXCTL, + NPCM7XX_MBOX_ALL_CIE, 0); +/* + * These registers are write one to clear. Clear them. + * Per spec, cleared bits should not be re-cleared. + * Need to read and clear needed bits only, instead of blindly clearing all. + */ + regmap_read(mbox->regmap, NPCM7XX_MBOX_BMBXSTAT, &val); + val &= NPCM7XX_MBOX_ALL_CIF; + + /* If any bit is set, write back to clear */ + if (val) + regmap_write_bits(mbox->regmap, NPCM7XX_MBOX_BMBXSTAT, + NPCM7XX_MBOX_ALL_CIF, val); + + irq = irq_of_parse_and_map(dev->of_node, 0); + if (!irq) + return -ENODEV; + + rc = devm_request_irq(dev, irq, npcm7xx_mbox_irq, 0, DEVICE_NAME, mbox); + if (rc < 0) { + dev_err(dev, "Unable to request IRQ %d\n", irq); + return rc; + } + + return 0; +} + +static int npcm7xx_mbox_probe(struct platform_device *pdev) +{ + struct npcm7xx_mbox *mbox; + struct device *dev; + struct resource *res; + int rc; + + dev = &pdev->dev; + + mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + dev_set_drvdata(&pdev->dev, mbox); + + mbox->regmap = syscon_node_to_regmap(dev->of_node); + if (IS_ERR(mbox->regmap)) { + dev_err(dev, "Couldn't get regmap\n"); + return -ENODEV; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + mbox->memory = devm_ioremap_resource(dev, res); + if (IS_ERR(mbox->memory)) + return PTR_ERR(mbox->memory); + mbox->max_buf_size = resource_size(res); + + spin_lock_init(&mbox->lock); + init_waitqueue_head(&mbox->queue); + + mbox->miscdev.minor = MISC_DYNAMIC_MINOR; + mbox->miscdev.name = DEVICE_NAME; + mbox->miscdev.fops = &npcm7xx_mbox_fops; + mbox->miscdev.parent = dev; + mbox->cif0 = false; + rc = misc_register(&mbox->miscdev); + if (rc) { + dev_err(dev, "Unable to register device\n"); + return rc; + } + + rc = npcm7xx_mbox_config_irq(mbox, pdev); + if (rc) { + dev_err(dev, "Failed to configure IRQ\n"); + misc_deregister(&mbox->miscdev); + return rc; + } + + pr_info("NPCM7xx PCI Mailbox probed\n"); + + return 0; +} + +static int npcm7xx_mbox_remove(struct platform_device *pdev) +{ + struct npcm7xx_mbox *mbox = dev_get_drvdata(&pdev->dev); + + misc_deregister(&mbox->miscdev); + + return 0; +} + +static const struct of_device_id npcm7xx_mbox_match[] = { + { .compatible = "nuvoton,npcm750-pci-mbox" }, + { }, +}; + +static struct platform_driver npcm7xx_mbox_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = npcm7xx_mbox_match, + }, + .probe = npcm7xx_mbox_probe, + .remove = npcm7xx_mbox_remove, +}; + +module_platform_driver(npcm7xx_mbox_driver); + +MODULE_DEVICE_TABLE(of, npcm7xx_mbox_match); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomer Maimon <tomer.maimon@nuvoton.com>"); +MODULE_DESCRIPTION("NPCM7XX mailbox device driver"); |