From 8adae0c8d822e54242694cdfed33cc9c346d607a Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 29 Aug 2013 16:57:33 +1000 Subject: [PATCH] powerpc/powernv: Add scom support under OPALv3 OPAL v3 provides interfaces to access the chips XSCOM, expose this via the existing scom infrastructure. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/platforms/powernv/Kconfig | 1 + arch/powerpc/platforms/powernv/Makefile | 1 + arch/powerpc/platforms/powernv/opal-xscom.c | 105 ++++++++++++++++++++ 3 files changed, 107 insertions(+) create mode 100644 arch/powerpc/platforms/powernv/opal-xscom.c diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platforms/powernv/Kconfig index 21084645c70a..9fced3f6d2dc 100644 --- a/arch/powerpc/platforms/powernv/Kconfig +++ b/arch/powerpc/platforms/powernv/Kconfig @@ -9,6 +9,7 @@ config PPC_POWERNV select EPAPR_BOOT select PPC_INDIRECT_PIO select PPC_UDBG_16550 + select PPC_SCOM select ARCH_RANDOM default y diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile index 6760a86d5bd0..050d57e0c788 100644 --- a/arch/powerpc/platforms/powernv/Makefile +++ b/arch/powerpc/platforms/powernv/Makefile @@ -4,3 +4,4 @@ obj-y += opal-rtc.o opal-nvram.o opal-lpc.o rng.o obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_PCI) += pci.o pci-p5ioc2.o pci-ioda.o obj-$(CONFIG_EEH) += eeh-ioda.o eeh-powernv.o +obj-$(CONFIG_PPC_SCOM) += opal-xscom.o diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c b/arch/powerpc/platforms/powernv/opal-xscom.c new file mode 100644 index 000000000000..3ed5c6498324 --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-xscom.c @@ -0,0 +1,105 @@ +/* + * PowerNV LPC bus handling. + * + * Copyright 2013 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 +#include +#include +#include +#include + +#include +#include +#include +#include + +/* + * We could probably fit that inside the scom_map_t + * which is a void* after all but it's really too ugly + * so let's kmalloc it for now + */ +struct opal_scom_map { + uint32_t chip; + uint32_t addr; +}; + +static scom_map_t opal_scom_map(struct device_node *dev, u64 reg, u64 count) +{ + struct opal_scom_map *m; + const __be32 *gcid; + + if (!of_get_property(dev, "scom-controller", NULL)) { + pr_err("%s: device %s is not a SCOM controller\n", + __func__, dev->full_name); + return SCOM_MAP_INVALID; + } + gcid = of_get_property(dev, "ibm,chip-id", NULL); + if (!gcid) { + pr_err("%s: device %s has no ibm,chip-id\n", + __func__, dev->full_name); + return SCOM_MAP_INVALID; + } + m = kmalloc(sizeof(struct opal_scom_map), GFP_KERNEL); + if (!m) + return NULL; + m->chip = be32_to_cpup(gcid); + m->addr = reg; + + return (scom_map_t)m; +} + +static void opal_scom_unmap(scom_map_t map) +{ + kfree(map); +} + +static int opal_xscom_err_xlate(int64_t rc) +{ + switch(rc) { + case 0: + return 0; + /* Add more translations if necessary */ + default: + return -EIO; + } +} + +static int opal_scom_read(scom_map_t map, u32 reg, u64 *value) +{ + struct opal_scom_map *m = map; + int64_t rc; + + rc = opal_xscom_read(m->chip, m->addr + reg, (uint64_t *)__pa(value)); + return opal_xscom_err_xlate(rc); +} + +static int opal_scom_write(scom_map_t map, u32 reg, u64 value) +{ + struct opal_scom_map *m = map; + int64_t rc; + + rc = opal_xscom_write(m->chip, m->addr + reg, value); + return opal_xscom_err_xlate(rc); +} + +static const struct scom_controller opal_scom_controller = { + .map = opal_scom_map, + .unmap = opal_scom_unmap, + .read = opal_scom_read, + .write = opal_scom_write +}; + +static int opal_xscom_init(void) +{ + if (firmware_has_feature(FW_FEATURE_OPALv3)) + scom_init(&opal_scom_controller); + return 0; +} +arch_initcall(opal_xscom_init); -- 2.34.1