[tip: x86/mtrr] x86/mtrr: Move 32-bit code from mtrr.c to legacy.c

From: tip-bot2 for Juergen Gross
Date: Mon Jun 05 2023 - 10:09:35 EST

The following commit has been merged into the x86/mtrr branch of tip:

Commit-ID: b5d3c72829b1f2b181cd7c5b426f7deaae452045
Gitweb: https://git.kernel.org/tip/b5d3c72829b1f2b181cd7c5b426f7deaae452045
Author: Juergen Gross <jgross@xxxxxxxx>
AuthorDate: Tue, 02 May 2023 14:09:23 +02:00
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Thu, 01 Jun 2023 15:04:33 +02:00

x86/mtrr: Move 32-bit code from mtrr.c to legacy.c

There is some code in mtrr.c which is relevant for old 32-bit CPUs
only. Move it to a new source legacy.c.

While modifying mtrr_init_finalize() fix spelling of its name.

Suggested-by: Borislav Petkov <bp@xxxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230502120931.20719-9-jgross@xxxxxxxx
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
---
arch/x86/kernel/cpu/mtrr/Makefile | 2 +-
arch/x86/kernel/cpu/mtrr/legacy.c | 84 ++++++++++++++++++++++++++++++-
arch/x86/kernel/cpu/mtrr/mtrr.c | 80 ++---------------------------
arch/x86/kernel/cpu/mtrr/mtrr.h | 7 +++-
4 files changed, 98 insertions(+), 75 deletions(-)
create mode 100644 arch/x86/kernel/cpu/mtrr/legacy.c

diff --git a/arch/x86/kernel/cpu/mtrr/Makefile b/arch/x86/kernel/cpu/mtrr/Makefile
index cc4f9f1..aee4bc5 100644
--- a/arch/x86/kernel/cpu/mtrr/Makefile
+++ b/arch/x86/kernel/cpu/mtrr/Makefile
@@ -1,4 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-y := mtrr.o if.o generic.o cleanup.o
-obj-$(CONFIG_X86_32) += amd.o cyrix.o centaur.o
+obj-$(CONFIG_X86_32) += amd.o cyrix.o centaur.o legacy.o

diff --git a/arch/x86/kernel/cpu/mtrr/legacy.c b/arch/x86/kernel/cpu/mtrr/legacy.c
new file mode 100644
index 0000000..7d379fb
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/legacy.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/types.h>
+#include <linux/syscore_ops.h>
+#include <asm/cpufeature.h>
+#include <asm/mtrr.h>
+#include <asm/processor.h>
+#include "mtrr.h"
+
+void mtrr_set_if(void)
+{
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_AMD:
+ /* Pre-Athlon (K6) AMD CPU MTRRs */
+ if (cpu_feature_enabled(X86_FEATURE_K6_MTRR))
+ mtrr_if = &amd_mtrr_ops;
+ break;
+ case X86_VENDOR_CENTAUR:
+ if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR))
+ mtrr_if = &centaur_mtrr_ops;
+ break;
+ case X86_VENDOR_CYRIX:
+ if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR))
+ mtrr_if = &cyrix_mtrr_ops;
+ break;
+ default:
+ break;
+ }
+}
+
+/*
+ * The suspend/resume methods are only for CPUs without MTRR. CPUs using generic
+ * MTRR driver don't require this.
+ */
+struct mtrr_value {
+ mtrr_type ltype;
+ unsigned long lbase;
+ unsigned long lsize;
+};
+
+static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];
+
+static int mtrr_save(void)
+{
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ mtrr_if->get(i, &mtrr_value[i].lbase,
+ &mtrr_value[i].lsize,
+ &mtrr_value[i].ltype);
+ }
+ return 0;
+}
+
+static void mtrr_restore(void)
+{
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ if (mtrr_value[i].lsize) {
+ mtrr_if->set(i, mtrr_value[i].lbase,
+ mtrr_value[i].lsize,
+ mtrr_value[i].ltype);
+ }
+ }
+}
+
+static struct syscore_ops mtrr_syscore_ops = {
+ .suspend = mtrr_save,
+ .resume = mtrr_restore,
+};
+
+void mtrr_register_syscore(void)
+{
+ /*
+ * The CPU has no MTRR and seems to not support SMP. They have
+ * specific drivers, we use a tricky method to support
+ * suspend/resume for them.
+ *
+ * TBD: is there any system with such CPU which supports
+ * suspend/resume? If no, we should remove the code.
+ */
+ register_syscore_ops(&mtrr_syscore_ops);
+}
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
index 007ecca..b7793a4 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.c
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -541,49 +541,6 @@ int arch_phys_wc_index(int handle)
}
EXPORT_SYMBOL_GPL(arch_phys_wc_index);

-/* The suspend/resume methods are only for CPU without MTRR. CPU using generic
- * MTRR driver doesn't require this
- */
-struct mtrr_value {
- mtrr_type ltype;
- unsigned long lbase;
- unsigned long lsize;
-};
-
-static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];
-
-static int mtrr_save(void)
-{
- int i;
-
- for (i = 0; i < num_var_ranges; i++) {
- mtrr_if->get(i, &mtrr_value[i].lbase,
- &mtrr_value[i].lsize,
- &mtrr_value[i].ltype);
- }
- return 0;
-}
-
-static void mtrr_restore(void)
-{
- int i;
-
- for (i = 0; i < num_var_ranges; i++) {
- if (mtrr_value[i].lsize) {
- mtrr_if->set(i, mtrr_value[i].lbase,
- mtrr_value[i].lsize,
- mtrr_value[i].ltype);
- }
- }
-}
-
-
-
-static struct syscore_ops mtrr_syscore_ops = {
- .suspend = mtrr_save,
- .resume = mtrr_restore,
-};
-
int __initdata changed_by_mtrr_cleanup;

/**
@@ -611,27 +568,10 @@ void __init mtrr_bp_init(void)
return;
}

- if (generic_mtrrs) {
+ if (generic_mtrrs)
mtrr_if = &generic_mtrr_ops;
- } else {
- switch (boot_cpu_data.x86_vendor) {
- case X86_VENDOR_AMD:
- /* Pre-Athlon (K6) AMD CPU MTRRs */
- if (cpu_feature_enabled(X86_FEATURE_K6_MTRR))
- mtrr_if = &amd_mtrr_ops;
- break;
- case X86_VENDOR_CENTAUR:
- if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR))
- mtrr_if = &centaur_mtrr_ops;
- break;
- case X86_VENDOR_CYRIX:
- if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR))
- mtrr_if = &cyrix_mtrr_ops;
- break;
- default:
- break;
- }
- }
+ else
+ mtrr_set_if();

if (mtrr_enabled()) {
/* Get the number of variable MTRR ranges. */
@@ -673,7 +613,7 @@ void mtrr_save_state(void)
smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
}

-static int __init mtrr_init_finialize(void)
+static int __init mtrr_init_finalize(void)
{
if (!mtrr_enabled())
return 0;
@@ -684,16 +624,8 @@ static int __init mtrr_init_finialize(void)
return 0;
}

- /*
- * The CPU has no MTRR and seems to not support SMP. They have
- * specific drivers, we use a tricky method to support
- * suspend/resume for them.
- *
- * TBD: is there any system with such CPU which supports
- * suspend/resume? If no, we should remove the code.
- */
- register_syscore_ops(&mtrr_syscore_ops);
+ mtrr_register_syscore();

return 0;
}
-subsys_initcall(mtrr_init_finialize);
+subsys_initcall(mtrr_init_finalize);
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h
index 6f3312b..e1e8864 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.h
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -61,6 +61,13 @@ extern u32 phys_hi_rsvd;
void mtrr_state_warn(void);
const char *mtrr_attrib_to_str(int x);
void mtrr_wrmsr(unsigned, unsigned, unsigned);
+#ifdef CONFIG_X86_32
+void mtrr_set_if(void);
+void mtrr_register_syscore(void);
+#else
+static inline void mtrr_set_if(void) { }
+static inline void mtrr_register_syscore(void) { }
+#endif

/* CPU specific mtrr_ops vectors. */
extern const struct mtrr_ops amd_mtrr_ops;