diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-10-25 10:06:04 +0200 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-10-25 10:06:04 +0200 |
commit | 0fc4f78f44e6c6148cee32456f0d0023ec1c1fd8 (patch) | |
tree | 71c906207227dd8753a0191db9304035ec3471a4 /arch/x86/kernel/acpi/cppc_msr.c | |
parent | 78010cd9736ec571796f4404524ed575b81238b9 (diff) | |
parent | 5481e27f6fd06b7cb902072e81d6b083db8155eb (diff) |
Merge remote-tracking branch 'airlied/drm-next' into topic/drm-misc
Backmerge latest drm-next to have a baseline for the
s/fence/dma_fence/ patch from Chris.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'arch/x86/kernel/acpi/cppc_msr.c')
-rw-r--r-- | arch/x86/kernel/acpi/cppc_msr.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/cppc_msr.c b/arch/x86/kernel/acpi/cppc_msr.c new file mode 100644 index 000000000000..6fb478bf82fd --- /dev/null +++ b/arch/x86/kernel/acpi/cppc_msr.c @@ -0,0 +1,58 @@ +/* + * cppc_msr.c: MSR Interface for CPPC + * Copyright (c) 2016, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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 <acpi/cppc_acpi.h> +#include <asm/msr.h> + +/* Refer to drivers/acpi/cppc_acpi.c for the description of functions */ + +bool cpc_ffh_supported(void) +{ + return true; +} + +int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val) +{ + int err; + + err = rdmsrl_safe_on_cpu(cpunum, reg->address, val); + if (!err) { + u64 mask = GENMASK_ULL(reg->bit_offset + reg->bit_width - 1, + reg->bit_offset); + + *val &= mask; + *val >>= reg->bit_offset; + } + return err; +} + +int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) +{ + u64 rd_val; + int err; + + err = rdmsrl_safe_on_cpu(cpunum, reg->address, &rd_val); + if (!err) { + u64 mask = GENMASK_ULL(reg->bit_offset + reg->bit_width - 1, + reg->bit_offset); + + val <<= reg->bit_offset; + val &= mask; + rd_val &= ~mask; + rd_val |= val; + err = wrmsrl_safe_on_cpu(cpunum, reg->address, rd_val); + } + return err; +} |