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authorDaniel Vetter <daniel.vetter@ffwll.ch>2016-10-25 10:06:04 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-10-25 10:06:04 +0200
commit0fc4f78f44e6c6148cee32456f0d0023ec1c1fd8 (patch)
tree71c906207227dd8753a0191db9304035ec3471a4 /arch/x86/kernel/acpi/cppc_msr.c
parent78010cd9736ec571796f4404524ed575b81238b9 (diff)
parent5481e27f6fd06b7cb902072e81d6b083db8155eb (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.c58
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;
+}