| /* |
| * Copyright (C) 2014-2017 Broadcom |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/types.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/interrupt.h> |
| #include <linux/sysfs.h> |
| #include <linux/io.h> |
| #include <linux/string.h> |
| #include <linux/device.h> |
| #include <linux/list.h> |
| #include <linux/of.h> |
| #include <linux/bitops.h> |
| #include <linux/pm.h> |
| |
| #ifdef CONFIG_ARM |
| #include <asm/bug.h> |
| #include <asm/signal.h> |
| #endif |
| |
| #ifdef CONFIG_MIPS |
| #include <asm/traps.h> |
| #endif |
| |
| #define ARB_ERR_CAP_CLEAR (1 << 0) |
| #define ARB_ERR_CAP_STATUS_TIMEOUT (1 << 12) |
| #define ARB_ERR_CAP_STATUS_TEA (1 << 11) |
| #define ARB_ERR_CAP_STATUS_WRITE (1 << 1) |
| #define ARB_ERR_CAP_STATUS_VALID (1 << 0) |
| |
| enum { |
| ARB_TIMER, |
| ARB_ERR_CAP_CLR, |
| ARB_ERR_CAP_HI_ADDR, |
| ARB_ERR_CAP_ADDR, |
| ARB_ERR_CAP_STATUS, |
| ARB_ERR_CAP_MASTER, |
| }; |
| |
| static const int gisb_offsets_bcm7038[] = { |
| [ARB_TIMER] = 0x00c, |
| [ARB_ERR_CAP_CLR] = 0x0c4, |
| [ARB_ERR_CAP_HI_ADDR] = -1, |
| [ARB_ERR_CAP_ADDR] = 0x0c8, |
| [ARB_ERR_CAP_STATUS] = 0x0d0, |
| [ARB_ERR_CAP_MASTER] = -1, |
| }; |
| |
| static const int gisb_offsets_bcm7400[] = { |
| [ARB_TIMER] = 0x00c, |
| [ARB_ERR_CAP_CLR] = 0x0c8, |
| [ARB_ERR_CAP_HI_ADDR] = -1, |
| [ARB_ERR_CAP_ADDR] = 0x0cc, |
| [ARB_ERR_CAP_STATUS] = 0x0d4, |
| [ARB_ERR_CAP_MASTER] = 0x0d8, |
| }; |
| |
| static const int gisb_offsets_bcm7435[] = { |
| [ARB_TIMER] = 0x00c, |
| [ARB_ERR_CAP_CLR] = 0x168, |
| [ARB_ERR_CAP_HI_ADDR] = -1, |
| [ARB_ERR_CAP_ADDR] = 0x16c, |
| [ARB_ERR_CAP_STATUS] = 0x174, |
| [ARB_ERR_CAP_MASTER] = 0x178, |
| }; |
| |
| static const int gisb_offsets_bcm7445[] = { |
| [ARB_TIMER] = 0x008, |
| [ARB_ERR_CAP_CLR] = 0x7e4, |
| [ARB_ERR_CAP_HI_ADDR] = 0x7e8, |
| [ARB_ERR_CAP_ADDR] = 0x7ec, |
| [ARB_ERR_CAP_STATUS] = 0x7f4, |
| [ARB_ERR_CAP_MASTER] = 0x7f8, |
| }; |
| |
| struct brcmstb_gisb_arb_device { |
| void __iomem *base; |
| const int *gisb_offsets; |
| bool big_endian; |
| struct mutex lock; |
| struct list_head next; |
| u32 valid_mask; |
| const char *master_names[sizeof(u32) * BITS_PER_BYTE]; |
| u32 saved_timeout; |
| }; |
| |
| static LIST_HEAD(brcmstb_gisb_arb_device_list); |
| |
| static u32 gisb_read(struct brcmstb_gisb_arb_device *gdev, int reg) |
| { |
| int offset = gdev->gisb_offsets[reg]; |
| |
| if (offset < 0) { |
| /* return 1 if the hardware doesn't have ARB_ERR_CAP_MASTER */ |
| if (reg == ARB_ERR_CAP_MASTER) |
| return 1; |
| else |
| return 0; |
| } |
| |
| if (gdev->big_endian) |
| return ioread32be(gdev->base + offset); |
| else |
| return ioread32(gdev->base + offset); |
| } |
| |
| static u64 gisb_read_address(struct brcmstb_gisb_arb_device *gdev) |
| { |
| u64 value; |
| |
| value = gisb_read(gdev, ARB_ERR_CAP_ADDR); |
| value |= (u64)gisb_read(gdev, ARB_ERR_CAP_HI_ADDR) << 32; |
| |
| return value; |
| } |
| |
| static void gisb_write(struct brcmstb_gisb_arb_device *gdev, u32 val, int reg) |
| { |
| int offset = gdev->gisb_offsets[reg]; |
| |
| if (offset == -1) |
| return; |
| |
| if (gdev->big_endian) |
| iowrite32be(val, gdev->base + offset); |
| else |
| iowrite32(val, gdev->base + offset); |
| } |
| |
| static ssize_t gisb_arb_get_timeout(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev); |
| u32 timeout; |
| |
| mutex_lock(&gdev->lock); |
| timeout = gisb_read(gdev, ARB_TIMER); |
| mutex_unlock(&gdev->lock); |
| |
| return sprintf(buf, "%d", timeout); |
| } |
| |
| static ssize_t gisb_arb_set_timeout(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev); |
| int val, ret; |
| |
| ret = kstrtoint(buf, 10, &val); |
| if (ret < 0) |
| return ret; |
| |
| if (val == 0 || val >= 0xffffffff) |
| return -EINVAL; |
| |
| mutex_lock(&gdev->lock); |
| gisb_write(gdev, val, ARB_TIMER); |
| mutex_unlock(&gdev->lock); |
| |
| return count; |
| } |
| |
| static const char * |
| brcmstb_gisb_master_to_str(struct brcmstb_gisb_arb_device *gdev, |
| u32 masters) |
| { |
| u32 mask = gdev->valid_mask & masters; |
| |
| if (hweight_long(mask) != 1) |
| return NULL; |
| |
| return gdev->master_names[ffs(mask) - 1]; |
| } |
| |
| static int brcmstb_gisb_arb_decode_addr(struct brcmstb_gisb_arb_device *gdev, |
| const char *reason) |
| { |
| u32 cap_status; |
| u64 arb_addr; |
| u32 master; |
| const char *m_name; |
| char m_fmt[11]; |
| |
| cap_status = gisb_read(gdev, ARB_ERR_CAP_STATUS); |
| |
| /* Invalid captured address, bail out */ |
| if (!(cap_status & ARB_ERR_CAP_STATUS_VALID)) |
| return 1; |
| |
| /* Read the address and master */ |
| arb_addr = gisb_read_address(gdev); |
| master = gisb_read(gdev, ARB_ERR_CAP_MASTER); |
| |
| m_name = brcmstb_gisb_master_to_str(gdev, master); |
| if (!m_name) { |
| snprintf(m_fmt, sizeof(m_fmt), "0x%08x", master); |
| m_name = m_fmt; |
| } |
| |
| pr_crit("%s: %s at 0x%llx [%c %s], core: %s\n", |
| __func__, reason, arb_addr, |
| cap_status & ARB_ERR_CAP_STATUS_WRITE ? 'W' : 'R', |
| cap_status & ARB_ERR_CAP_STATUS_TIMEOUT ? "timeout" : "", |
| m_name); |
| |
| /* clear the GISB error */ |
| gisb_write(gdev, ARB_ERR_CAP_CLEAR, ARB_ERR_CAP_CLR); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_ARM |
| static int brcmstb_bus_error_handler(unsigned long addr, unsigned int fsr, |
| struct pt_regs *regs) |
| { |
| int ret = 0; |
| struct brcmstb_gisb_arb_device *gdev; |
| |
| /* iterate over each GISB arb registered handlers */ |
| list_for_each_entry(gdev, &brcmstb_gisb_arb_device_list, next) |
| ret |= brcmstb_gisb_arb_decode_addr(gdev, "bus error"); |
| /* |
| * If it was an imprecise abort, then we need to correct the |
| * return address to be _after_ the instruction. |
| */ |
| if (fsr & (1 << 10)) |
| regs->ARM_pc += 4; |
| |
| return ret; |
| } |
| #endif |
| |
| #ifdef CONFIG_MIPS |
| static int brcmstb_bus_error_handler(struct pt_regs *regs, int is_fixup) |
| { |
| int ret = 0; |
| struct brcmstb_gisb_arb_device *gdev; |
| u32 cap_status; |
| |
| list_for_each_entry(gdev, &brcmstb_gisb_arb_device_list, next) { |
| cap_status = gisb_read(gdev, ARB_ERR_CAP_STATUS); |
| |
| /* Invalid captured address, bail out */ |
| if (!(cap_status & ARB_ERR_CAP_STATUS_VALID)) { |
| is_fixup = 1; |
| goto out; |
| } |
| |
| ret |= brcmstb_gisb_arb_decode_addr(gdev, "bus error"); |
| } |
| out: |
| return is_fixup ? MIPS_BE_FIXUP : MIPS_BE_FATAL; |
| } |
| #endif |
| |
| static irqreturn_t brcmstb_gisb_timeout_handler(int irq, void *dev_id) |
| { |
| brcmstb_gisb_arb_decode_addr(dev_id, "timeout"); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t brcmstb_gisb_tea_handler(int irq, void *dev_id) |
| { |
| brcmstb_gisb_arb_decode_addr(dev_id, "target abort"); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static DEVICE_ATTR(gisb_arb_timeout, S_IWUSR | S_IRUGO, |
| gisb_arb_get_timeout, gisb_arb_set_timeout); |
| |
| static struct attribute *gisb_arb_sysfs_attrs[] = { |
| &dev_attr_gisb_arb_timeout.attr, |
| NULL, |
| }; |
| |
| static struct attribute_group gisb_arb_sysfs_attr_group = { |
| .attrs = gisb_arb_sysfs_attrs, |
| }; |
| |
| static const struct of_device_id brcmstb_gisb_arb_of_match[] = { |
| { .compatible = "brcm,gisb-arb", .data = gisb_offsets_bcm7445 }, |
| { .compatible = "brcm,bcm7445-gisb-arb", .data = gisb_offsets_bcm7445 }, |
| { .compatible = "brcm,bcm7435-gisb-arb", .data = gisb_offsets_bcm7435 }, |
| { .compatible = "brcm,bcm7400-gisb-arb", .data = gisb_offsets_bcm7400 }, |
| { .compatible = "brcm,bcm7038-gisb-arb", .data = gisb_offsets_bcm7038 }, |
| { }, |
| }; |
| |
| static int __init brcmstb_gisb_arb_probe(struct platform_device *pdev) |
| { |
| struct device_node *dn = pdev->dev.of_node; |
| struct brcmstb_gisb_arb_device *gdev; |
| const struct of_device_id *of_id; |
| struct resource *r; |
| int err, timeout_irq, tea_irq; |
| unsigned int num_masters, j = 0; |
| int i, first, last; |
| |
| r = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| timeout_irq = platform_get_irq(pdev, 0); |
| tea_irq = platform_get_irq(pdev, 1); |
| |
| gdev = devm_kzalloc(&pdev->dev, sizeof(*gdev), GFP_KERNEL); |
| if (!gdev) |
| return -ENOMEM; |
| |
| mutex_init(&gdev->lock); |
| INIT_LIST_HEAD(&gdev->next); |
| |
| gdev->base = devm_ioremap_resource(&pdev->dev, r); |
| if (IS_ERR(gdev->base)) |
| return PTR_ERR(gdev->base); |
| |
| of_id = of_match_node(brcmstb_gisb_arb_of_match, dn); |
| if (!of_id) { |
| pr_err("failed to look up compatible string\n"); |
| return -EINVAL; |
| } |
| gdev->gisb_offsets = of_id->data; |
| gdev->big_endian = of_device_is_big_endian(dn); |
| |
| err = devm_request_irq(&pdev->dev, timeout_irq, |
| brcmstb_gisb_timeout_handler, 0, pdev->name, |
| gdev); |
| if (err < 0) |
| return err; |
| |
| err = devm_request_irq(&pdev->dev, tea_irq, |
| brcmstb_gisb_tea_handler, 0, pdev->name, |
| gdev); |
| if (err < 0) |
| return err; |
| |
| /* If we do not have a valid mask, assume all masters are enabled */ |
| if (of_property_read_u32(dn, "brcm,gisb-arb-master-mask", |
| &gdev->valid_mask)) |
| gdev->valid_mask = 0xffffffff; |
| |
| /* Proceed with reading the litteral names if we agree on the |
| * number of masters |
| */ |
| num_masters = of_property_count_strings(dn, |
| "brcm,gisb-arb-master-names"); |
| if (hweight_long(gdev->valid_mask) == num_masters) { |
| first = ffs(gdev->valid_mask) - 1; |
| last = fls(gdev->valid_mask) - 1; |
| |
| for (i = first; i < last; i++) { |
| if (!(gdev->valid_mask & BIT(i))) |
| continue; |
| |
| of_property_read_string_index(dn, |
| "brcm,gisb-arb-master-names", j, |
| &gdev->master_names[i]); |
| j++; |
| } |
| } |
| |
| err = sysfs_create_group(&pdev->dev.kobj, &gisb_arb_sysfs_attr_group); |
| if (err) |
| return err; |
| |
| platform_set_drvdata(pdev, gdev); |
| |
| list_add_tail(&gdev->next, &brcmstb_gisb_arb_device_list); |
| |
| #ifdef CONFIG_ARM |
| hook_fault_code(22, brcmstb_bus_error_handler, SIGBUS, 0, |
| "imprecise external abort"); |
| #endif |
| #ifdef CONFIG_MIPS |
| board_be_handler = brcmstb_bus_error_handler; |
| #endif |
| |
| dev_info(&pdev->dev, "registered mem: %p, irqs: %d, %d\n", |
| gdev->base, timeout_irq, tea_irq); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int brcmstb_gisb_arb_suspend(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev); |
| |
| gdev->saved_timeout = gisb_read(gdev, ARB_TIMER); |
| |
| return 0; |
| } |
| |
| /* Make sure we provide the same timeout value that was configured before, and |
| * do this before the GISB timeout interrupt handler has any chance to run. |
| */ |
| static int brcmstb_gisb_arb_resume_noirq(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct brcmstb_gisb_arb_device *gdev = platform_get_drvdata(pdev); |
| |
| gisb_write(gdev, gdev->saved_timeout, ARB_TIMER); |
| |
| return 0; |
| } |
| #else |
| #define brcmstb_gisb_arb_suspend NULL |
| #define brcmstb_gisb_arb_resume_noirq NULL |
| #endif |
| |
| static const struct dev_pm_ops brcmstb_gisb_arb_pm_ops = { |
| .suspend = brcmstb_gisb_arb_suspend, |
| .resume_noirq = brcmstb_gisb_arb_resume_noirq, |
| }; |
| |
| static struct platform_driver brcmstb_gisb_arb_driver = { |
| .driver = { |
| .name = "brcm-gisb-arb", |
| .of_match_table = brcmstb_gisb_arb_of_match, |
| .pm = &brcmstb_gisb_arb_pm_ops, |
| }, |
| }; |
| |
| static int __init brcm_gisb_driver_init(void) |
| { |
| return platform_driver_probe(&brcmstb_gisb_arb_driver, |
| brcmstb_gisb_arb_probe); |
| } |
| |
| module_init(brcm_gisb_driver_init); |