From 628daa8d5abfd904a7329a660c5c374212230123 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Mon, 19 Sep 2011 17:45:01 +0000 Subject: powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks Implements OPAL RTC and NVRAM support and wire all that up to the powernv platform. We use RTAS for RTC as a fallback if available. Using RTAS for nvram is not supported yet, pending some rework/cleanup and generalization of the pSeries & CHRP code. We also use RTAS fallbacks for power off and reboot Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/platforms/powernv/opal-nvram.c | 88 +++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 arch/powerpc/platforms/powernv/opal-nvram.c (limited to 'arch/powerpc/platforms/powernv/opal-nvram.c') diff --git a/arch/powerpc/platforms/powernv/opal-nvram.c b/arch/powerpc/platforms/powernv/opal-nvram.c new file mode 100644 index 000000000000..3f83e1ae26ac --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-nvram.c @@ -0,0 +1,88 @@ +/* + * PowerNV nvram code. + * + * Copyright 2011 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. + */ + +#define DEBUG + +#include +#include +#include + +#include +#include + +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; +} + +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) + opal_poll_events(NULL); + } + *index += count; + return count; +} + +void __init opal_nvram_init(void) +{ + struct device_node *np; + const u32 *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 = *nbytes_p; + + printk(KERN_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; +} + -- cgit v1.2.3