Move the common code for saving and restoring platform specific COP2
registers to switch_to(). This will make supporting new platforms (like
Netlogic XLP) easier.
The platform specific COP2 definitions are to be specified in
asm/processor.h and in asm/cop2.h.
Signed-off-by: Jayachandran C <jchandra@xxxxxxxxxxxx>
---
arch/mips/include/asm/cop2.h | 19 +++++++++++++++++++
arch/mips/include/asm/processor.h | 18 +++++++-----------
arch/mips/include/asm/switch_to.h | 19 ++++++++++++++++++-
arch/mips/kernel/octeon_switch.S | 27 ---------------------------
4 files changed, 44 insertions(+), 39 deletions(-)
diff --git a/arch/mips/include/asm/cop2.h b/arch/mips/include/asm/cop2.h
index 3532e2c..b17f38e 100644
--- a/arch/mips/include/asm/cop2.h
+++ b/arch/mips/include/asm/cop2.h
@@ -11,6 +11,25 @@
#include <linux/notifier.h>
+#if defined(CONFIG_CPU_CAVIUM_OCTEON)
+
+extern void octeon_cop2_save(struct octeon_cop2_state *);
+extern void octeon_cop2_restore(struct octeon_cop2_state *);
+
+#define cop2_save(r) octeon_cop2_save(r)
+#define cop2_restore(r) octeon_cop2_restore(r)
+
+#define cop2_present 1
+#define cop2_lazy_restore 1
+
+#else
+
+#define cop2_present 0
+#define cop2_lazy_restore 0
+#define cop2_save(r)
+#define cop2_restore(r)
+#endif
+
enum cu2_ops {
CU2_EXCEPTION,
CU2_LWC2_OP,
diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
index 1470b7b..7c637a4 100644
--- a/arch/mips/include/asm/processor.h
+++ b/arch/mips/include/asm/processor.h
@@ -137,7 +137,7 @@ union mips_watch_reg_state {
struct mips3264_watch_reg_state mips3264;
};
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
+#if defined(CONFIG_CPU_CAVIUM_OCTEON)
struct octeon_cop2_state {
/* DMFC2 rt, 0x0201 */
@@ -182,13 +182,16 @@ struct octeon_cop2_state {
/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
unsigned long cop2_gfm_result[2];
};
-#define INIT_OCTEON_COP2 {0,}
+#define COP2_INIT \
+ .cp2 = {0,},
struct octeon_cvmseg_state {
unsigned long cvmseg[CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE]
[cpu_dcache_line_size() / sizeof(unsigned long)];
};
+#else
+#define COP2_INIT
#endif
typedef struct {
@@ -245,13 +248,6 @@ struct thread_struct {
#define FPAFF_INIT
#endif /* CONFIG_MIPS_MT_FPAFF */
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
-#define OCTEON_INIT \
- .cp2 = INIT_OCTEON_COP2,
-#else
-#define OCTEON_INIT
-#endif /* CONFIG_CPU_CAVIUM_OCTEON */
-
#define INIT_THREAD { \
/* \
* Saved main processor registers \
@@ -300,9 +296,9 @@ struct thread_struct {
.cp0_baduaddr = 0, \
.error_code = 0, \
/* \
- * Cavium Octeon specifics (null if not Octeon) \
+ * Platform specific cop2 registers(null if no COP2) \
*/ \
- OCTEON_INIT \
+ COP2_INIT \
}
struct task_struct;
diff --git a/arch/mips/include/asm/switch_to.h b/arch/mips/include/asm/switch_to.h
index fd16bcb..eb0af15 100644
--- a/arch/mips/include/asm/switch_to.h
+++ b/arch/mips/include/asm/switch_to.h
@@ -15,6 +15,7 @@
#include <asm/cpu-features.h>
#include <asm/watch.h>
#include <asm/dsp.h>
+#include <asm/cop2.h>
struct task_struct;
@@ -66,10 +67,18 @@ do { \
#define switch_to(prev, next, last) \
do { \
- u32 __usedfpu; \
+ u32 __usedfpu, __c0_stat; \
__mips_mt_fpaff_switch_to(prev); \
if (cpu_has_dsp) \
__save_dsp(prev); \
+ if (cop2_present && (KSTK_STATUS(prev) & ST0_CU2)) { \
+ if (cop2_lazy_restore) \
+ KSTK_STATUS(prev) &= ~ST0_CU2; \
+ __c0_stat = read_c0_status(); \
+ write_c0_status(__c0_stat | ST0_CU2); \
+ cop2_save(&prev->thread.cp2); \
+ write_c0_status(__c0_stat & ~ST0_CU2); \
+ } \
__clear_software_ll_bit(); \
__usedfpu = test_and_clear_tsk_thread_flag(prev, TIF_USEDFPU); \
(last) = resume(prev, next, task_thread_info(next), __usedfpu); \
@@ -77,6 +86,14 @@ do { \
#define finish_arch_switch(prev) \
do { \
+ u32 __c0_stat; \
+ if (cop2_present && !cop2_lazy_restore && \
+ (KSTK_STATUS(current) & ST0_CU2)) { \
+ __c0_stat = read_c0_status(); \
+ write_c0_status(__c0_stat | ST0_CU2); \
+ cop2_restore(¤t->thread.cp2); \
+ write_c0_status(__c0_stat & ~ST0_CU2); \
+ } \
if (cpu_has_dsp) \
__restore_dsp(current); \
if (cpu_has_userlocal) \
diff --git a/arch/mips/kernel/octeon_switch.S b/arch/mips/kernel/octeon_switch.S
index 0e23343..22e2aa1 100644
--- a/arch/mips/kernel/octeon_switch.S
+++ b/arch/mips/kernel/octeon_switch.S
@@ -40,33 +40,6 @@
cpu_save_nonscratch a0
LONG_S ra, THREAD_REG31(a0)
- /* check if we need to save COP2 registers */
- PTR_L t2, TASK_THREAD_INFO(a0)
- LONG_L t0, ST_OFF(t2)
- bbit0 t0, 30, 1f
-
- /* Disable COP2 in the stored process state */
- li t1, ST0_CU2
- xor t0, t1
- LONG_S t0, ST_OFF(t2)
-
- /* Enable COP2 so we can save it */
- mfc0 t0, CP0_STATUS
- or t0, t1
- mtc0 t0, CP0_STATUS
-
- /* Save COP2 */
- daddu a0, THREAD_CP2
- jal octeon_cop2_save
- dsubu a0, THREAD_CP2
-
- /* Disable COP2 now that we are done */
- mfc0 t0, CP0_STATUS
- li t1, ST0_CU2
- xor t0, t1
- mtc0 t0, CP0_STATUS
-
-1:
#if CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0
/* Check if we need to store CVMSEG state */
mfc0 t0, $11,7 /* CvmMemCtl */
--
1.7.9.5
