/* * 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> #include <linux/kernel.h> #include <linux/kdebug.h> #include <linux/notifier.h> #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_bcm7278[] = { [ARB_TIMER] = 0x008, [ARB_ERR_CAP_CLR] = 0x7f8, [ARB_ERR_CAP_HI_ADDR] = -1, [ARB_ERR_CAP_ADDR] = 0x7e0, [ARB_ERR_CAP_STATUS] = 0x7f0, [ARB_ERR_CAP_MASTER] = 0x7f4, }; 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_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; } /* * Dump out gisb errors on die or panic. */ static int dump_gisb_error(struct notifier_block *self, unsigned long v, void *p); static struct notifier_block gisb_die_notifier = { .notifier_call = dump_gisb_error, }; static struct notifier_block gisb_panic_notifier = { .notifier_call = dump_gisb_error, }; static int dump_gisb_error(struct notifier_block *self, unsigned long v, void *p) { struct brcmstb_gisb_arb_device *gdev; const char *reason = "panic"; if (self == &gisb_die_notifier) reason = "die"; /* iterate over each GISB arb registered handlers */ list_for_each_entry(gdev, &brcmstb_gisb_arb_device_list, next) brcmstb_gisb_arb_decode_addr(gdev, reason); return NOTIFY_DONE; } 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,bcm7278-gisb-arb", .data = gisb_offsets_bcm7278 }, { .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_MIPS board_be_handler = brcmstb_bus_error_handler; #endif if (list_is_singular(&brcmstb_gisb_arb_device_list)) { register_die_notifier(&gisb_die_notifier); atomic_notifier_chain_register(&panic_notifier_list, &gisb_panic_notifier); } 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);