From 2c952e06e4f57716109b609956eda28c900faac0 Mon Sep 17 00:00:00 2001 From: Jayachandran C Date: Mon, 10 Jun 2013 06:30:00 +0000 Subject: [PATCH] MIPS: Move cop2 save/restore to switch_to() 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 Cc: linux-mips@linux-mips.org Cc: ddaney.cavm@gmail.com Patchwork: https://patchwork.linux-mips.org/patch/5411/ Signed-off-by: Ralf Baechle --- 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 3532e2c5f098..b17f38ee1ed4 100644 --- a/arch/mips/include/asm/cop2.h +++ b/arch/mips/include/asm/cop2.h @@ -11,6 +11,25 @@ #include +#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 1470b7b68b0e..7c637a461ced 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 fd16bcb6c311..eb0af15ac656 100644 --- a/arch/mips/include/asm/switch_to.h +++ b/arch/mips/include/asm/switch_to.h @@ -15,6 +15,7 @@ #include #include #include +#include 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 0e23343eb0a9..22e2aa1e8d37 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 */ -- 2.30.2