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authorMark Brown <broonie@kernel.org>2016-11-04 12:16:38 -0600
committerMark Brown <broonie@kernel.org>2016-11-04 12:16:38 -0600
commitcc9b94029e9ef51787af908e9856b1eed314bc00 (patch)
tree9675310b89d0f6fb1f7bd9423f0638c4ee5226fd /arch/x86/kernel/acpi/cppc_msr.c
parent13bed58ce8748d430a26e353a09b89f9d613a71f (diff)
parent1b5b42216469b05ef4b5916cb40b127dfab1da88 (diff)
downloadtalos-op-linux-cc9b94029e9ef51787af908e9856b1eed314bc00.tar.gz
talos-op-linux-cc9b94029e9ef51787af908e9856b1eed314bc00.zip
Merge branch 'topic/error' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-fixed
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;
+}
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