diff options
| -rw-r--r-- | arch/powerpc/include/asm/opal.h | 4 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/Makefile | 1 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal-msglog.c | 120 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal.c | 4 |
4 files changed, 128 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index a13ab397edda..05f9455615d6 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -730,6 +730,9 @@ typedef struct oppanel_line { /* /sys/firmware/opal */ extern struct kobject *opal_kobj; +/* /ibm,opal */ +extern struct device_node *opal_node; + /* API functions */ int64_t opal_console_write(int64_t term_number, __be64 *length, const uint8_t *buffer); @@ -920,6 +923,7 @@ extern void opal_flash_init(void); extern int opal_elog_init(void); extern void opal_platform_dump_init(void); extern void opal_sys_param_init(void); +extern void opal_msglog_init(void); extern int opal_machine_check(struct pt_regs *regs); extern bool opal_mce_check_early_recovery(struct pt_regs *regs); diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile index f324ea099503..63cebb9b4d45 100644 --- a/arch/powerpc/platforms/powernv/Makefile +++ b/arch/powerpc/platforms/powernv/Makefile @@ -1,6 +1,7 @@ obj-y += setup.o opal-takeover.o opal-wrappers.o opal.o opal-async.o obj-y += opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o obj-y += rng.o opal-elog.o opal-dump.o opal-sysparam.o opal-sensor.o +obj-y += opal-msglog.o obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_PCI) += pci.o pci-p5ioc2.o pci-ioda.o diff --git a/arch/powerpc/platforms/powernv/opal-msglog.c b/arch/powerpc/platforms/powernv/opal-msglog.c new file mode 100644 index 000000000000..1bb25b952504 --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-msglog.c @@ -0,0 +1,120 @@ +/* + * PowerNV OPAL in-memory console interface + * + * Copyright 2014 IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <asm/io.h> +#include <asm/opal.h> +#include <linux/debugfs.h> +#include <linux/of.h> +#include <linux/types.h> +#include <asm/barrier.h> + +/* OPAL in-memory console. Defined in OPAL source at core/console.c */ +struct memcons { + __be64 magic; +#define MEMCONS_MAGIC 0x6630696567726173L + __be64 obuf_phys; + __be64 ibuf_phys; + __be32 obuf_size; + __be32 ibuf_size; + __be32 out_pos; +#define MEMCONS_OUT_POS_WRAP 0x80000000u +#define MEMCONS_OUT_POS_MASK 0x00ffffffu + __be32 in_prod; + __be32 in_cons; +}; + +static ssize_t opal_msglog_read(struct file *file, struct kobject *kobj, + struct bin_attribute *bin_attr, char *to, + loff_t pos, size_t count) +{ + struct memcons *mc = bin_attr->private; + const char *conbuf; + size_t ret, first_read = 0; + uint32_t out_pos, avail; + + if (!mc) + return -ENODEV; + + out_pos = be32_to_cpu(ACCESS_ONCE(mc->out_pos)); + + /* Now we've read out_pos, put a barrier in before reading the new + * data it points to in conbuf. */ + smp_rmb(); + + conbuf = phys_to_virt(be64_to_cpu(mc->obuf_phys)); + + /* When the buffer has wrapped, read from the out_pos marker to the end + * of the buffer, and then read the remaining data as in the un-wrapped + * case. */ + if (out_pos & MEMCONS_OUT_POS_WRAP) { + + out_pos &= MEMCONS_OUT_POS_MASK; + avail = be32_to_cpu(mc->obuf_size) - out_pos; + + ret = memory_read_from_buffer(to, count, &pos, + conbuf + out_pos, avail); + + if (ret < 0) + goto out; + + first_read = ret; + to += first_read; + count -= first_read; + pos -= avail; + } + + /* Sanity check. The firmware should not do this to us. */ + if (out_pos > be32_to_cpu(mc->obuf_size)) { + pr_err("OPAL: memory console corruption. Aborting read.\n"); + return -EINVAL; + } + + ret = memory_read_from_buffer(to, count, &pos, conbuf, out_pos); + + if (ret < 0) + goto out; + + ret += first_read; +out: + return ret; +} + +static struct bin_attribute opal_msglog_attr = { + .attr = {.name = "msglog", .mode = 0444}, + .read = opal_msglog_read +}; + +void __init opal_msglog_init(void) +{ + u64 mcaddr; + struct memcons *mc; + + if (of_property_read_u64(opal_node, "ibm,opal-memcons", &mcaddr)) { + pr_warn("OPAL: Property ibm,opal-memcons not found, no message log\n"); + return; + } + + mc = phys_to_virt(mcaddr); + if (!mc) { + pr_warn("OPAL: memory console address is invalid\n"); + return; + } + + if (be64_to_cpu(mc->magic) != MEMCONS_MAGIC) { + pr_warn("OPAL: memory console version is invalid\n"); + return; + } + + opal_msglog_attr.private = mc; + + if (sysfs_create_bin_file(opal_kobj, &opal_msglog_attr) != 0) + pr_warn("OPAL: sysfs file creation failed\n"); +} diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 3697772e3759..99e9c2887e21 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -46,7 +46,7 @@ struct mcheck_recoverable_range { static struct mcheck_recoverable_range *mc_recoverable_range; static int mc_recoverable_range_len; -static struct device_node *opal_node; +struct device_node *opal_node; static DEFINE_SPINLOCK(opal_write_lock); extern u64 opal_mc_secondary_handler[]; static unsigned int *opal_irqs; @@ -602,6 +602,8 @@ static int __init opal_init(void) opal_platform_dump_init(); /* Setup system parameters interface */ opal_sys_param_init(); + /* Setup message log interface. */ + opal_msglog_init(); } return 0; |