linux_dsm_epyc7002/arch/powerpc/platforms/powernv/opal-nvram.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

114 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PowerNV nvram code.
*
* Copyright 2011 IBM Corp.
*/
#define DEBUG
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of.h>
#include <asm/opal.h>
#include <asm/nvram.h>
#include <asm/machdep.h>
static unsigned int nvram_size;
static ssize_t opal_nvram_size(void)
{
return nvram_size;
}
static ssize_t opal_nvram_read(char *buf, size_t count, loff_t *index)
{
s64 rc;
int off;
if (*index >= nvram_size)
return 0;
off = *index;
if ((off + count) > nvram_size)
count = nvram_size - off;
rc = opal_read_nvram(__pa(buf), count, off);
if (rc != OPAL_SUCCESS)
return -EIO;
*index += count;
return count;
}
/*
* This can be called in the panic path with interrupts off, so use
* mdelay in that case.
*/
static ssize_t opal_nvram_write(char *buf, size_t count, loff_t *index)
{
s64 rc = OPAL_BUSY;
int off;
if (*index >= nvram_size)
return 0;
off = *index;
if ((off + count) > nvram_size)
count = nvram_size - off;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_write_nvram(__pa(buf), count, off);
if (rc == OPAL_BUSY_EVENT) {
if (in_interrupt() || irqs_disabled())
mdelay(OPAL_BUSY_DELAY_MS);
else
msleep(OPAL_BUSY_DELAY_MS);
opal_poll_events(NULL);
} else if (rc == OPAL_BUSY) {
if (in_interrupt() || irqs_disabled())
mdelay(OPAL_BUSY_DELAY_MS);
else
msleep(OPAL_BUSY_DELAY_MS);
}
}
if (rc)
return -EIO;
*index += count;
return count;
}
static int __init opal_nvram_init_log_partitions(void)
{
/* Scan nvram for partitions */
nvram_scan_partitions();
nvram_init_oops_partition(0);
return 0;
}
machine_arch_initcall(powernv, opal_nvram_init_log_partitions);
void __init opal_nvram_init(void)
{
struct device_node *np;
const __be32 *nbytes_p;
np = of_find_compatible_node(NULL, NULL, "ibm,opal-nvram");
if (np == NULL)
return;
nbytes_p = of_get_property(np, "#bytes", NULL);
if (!nbytes_p) {
of_node_put(np);
return;
}
nvram_size = be32_to_cpup(nbytes_p);
pr_info("OPAL nvram setup, %u bytes\n", nvram_size);
of_node_put(np);
ppc_md.nvram_read = opal_nvram_read;
ppc_md.nvram_write = opal_nvram_write;
ppc_md.nvram_size = opal_nvram_size;
}