[PATCH V7 0/9] MIPS: Loongson: feature and performance improvements

[PATCH V7 0/9] MIPS: Loongson: feature and performance improvements

[Huacai Chen]

This patchset is is prepared for the next 4.13 release for Linux/MIPS.
It adds Loongson-3A R3 and Loongson's NMI handler support, adds a
"model name" knob in /proc/cpuinfo which is needed by some userspace
tools, improves I/O performance by IRQ balancing and IRQ affinity
setting, fixes indexed scache flushing for Loongson-3, and introduces
LOONGSON_LLSC_WAR to improve stability.

V1 -> V2:
1, Add Loongson-3A R3 basic support.
2, Sync the code to upstream.

V2 -> V3:
1, Add r4k_blast_scache_node for Loongson-3.
2, Update the last patch to avoid miscompilation.
3, Sync the code to upstream.

V3 -> V4:
1, Support 4 packages in CPU Hwmon driver.
2, ICT is dropped in cpu name, and cpu name can be overwritten by BIOS.
3, Sync the code to upstream.

V4 -> V5:
1, Drop some #ifdefs in the 2nd patch.
2, Improve maintainability of the 4th patch.
3, Sync the code to upstream.

V5 -> V6:
1, Update commit message in the 2nd patch.
2, Drop #ifdefs and set irq_set_affinity() at runtime in the 6th patch.
3, Sync the code to upstream.

V6 -> V7:
1, Fix bnez/beqz mistake in the last patch.
2, Sync the code to upstream.

Huacai Chen(9):
 MIPS: Loongson: Add Loongson-3A R3 basic support.
 MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3.
 MIPS: Loongson: Add NMI handler support.
 MIPS: Loongson-3: Support 4 packages in CPU Hwmon driver.
 MIPS: Loongson-3: IRQ balancing for PCI devices.
 MIPS: Loongson-3: support irq_set_affinity() in i8259 chip.
 MIPS: Loogson: Make enum loongson_cpu_type more clear.
 MIPS: Add __cpu_full_name[] to make CPU names more human-readable.
 MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/atomic.h                     | 107 ++++++++
 arch/mips/include/asm/bitops.h                     | 273 ++++++++++++++++-----
 arch/mips/include/asm/cmpxchg.h                    |  54 ++++
 arch/mips/include/asm/cpu-info.h                   |   2 +
 arch/mips/include/asm/cpu.h                        |   1 +
 arch/mips/include/asm/edac.h                       |  33 ++-
 arch/mips/include/asm/futex.h                      |  62 +++++
 arch/mips/include/asm/irq.h                        |   3 +
 arch/mips/include/asm/local.h                      |  34 +++
 arch/mips/include/asm/mach-cavium-octeon/war.h     |   1 +
 arch/mips/include/asm/mach-generic/war.h           |   1 +
 arch/mips/include/asm/mach-ip22/war.h              |   1 +
 arch/mips/include/asm/mach-ip27/war.h              |   1 +
 arch/mips/include/asm/mach-ip28/war.h              |   1 +
 arch/mips/include/asm/mach-ip32/war.h              |   1 +
 arch/mips/include/asm/mach-loongson64/boot_param.h |  23 +-
 arch/mips/include/asm/mach-loongson64/war.h        |  26 ++
 arch/mips/include/asm/mach-malta/war.h             |   1 +
 arch/mips/include/asm/mach-pmcs-msp71xx/war.h      |   1 +
 arch/mips/include/asm/mach-rc32434/war.h           |   1 +
 arch/mips/include/asm/mach-rm/war.h                |   1 +
 arch/mips/include/asm/mach-sibyte/war.h            |   1 +
 arch/mips/include/asm/mach-tx49xx/war.h            |   1 +
 arch/mips/include/asm/pgtable.h                    |  19 ++
 arch/mips/include/asm/r4kcache.h                   |  30 +++
 arch/mips/include/asm/spinlock.h                   | 142 +++++++++++
 arch/mips/include/asm/war.h                        |   8 +
 arch/mips/kernel/cpu-probe.c                       |  29 ++-
 arch/mips/kernel/proc.c                            |   4 +
 arch/mips/kernel/syscall.c                         |  34 +++
 arch/mips/loongson64/Platform                      |   3 +
 arch/mips/loongson64/common/env.c                  |  30 ++-
 arch/mips/loongson64/common/init.c                 |  13 +
 arch/mips/loongson64/loongson-3/irq.c              |  53 +++-
 arch/mips/loongson64/loongson-3/smp.c              |  23 +-
 arch/mips/mm/c-r4k.c                               |  42 +++-
 arch/mips/mm/tlbex.c                               |  17 ++
 drivers/irqchip/irq-i8259.c                        |   3 +
 drivers/platform/mips/cpu_hwmon.c                  | 136 +++++-----
 39 files changed, 1059 insertions(+), 157 deletions(-)
 create mode 100644 arch/mips/include/asm/mach-loongson64/war.h
--
2.7.0

[PATCH V7 1/9] MIPS: Loongson: Add Loongson-3A R3 basic support

[Huacai Chen]

Loongson-3A R3 is very similar to Loongson-3A R2.

All Loongson-3 CPU family:

Code-name       Brand-name       PRId
Loongson-3A R1  Loongson-3A1000  0x6305
Loongson-3A R2  Loongson-3A2000  0x6308
Loongson-3A R3  Loongson-3A3000  0x6309
Loongson-3B R1  Loongson-3B1000  0x6306
Loongson-3B R2  Loongson-3B1500  0x6307

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/cpu.h           |  1 +
 arch/mips/kernel/cpu-probe.c          |  6 ++++++
 arch/mips/loongson64/common/env.c     |  1 +
 arch/mips/loongson64/loongson-3/smp.c |  5 +++--
 drivers/platform/mips/cpu_hwmon.c     | 17 +++++++++++++----
 5 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index 3069359..53b8b1f 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -248,6 +248,7 @@
 #define PRID_REV_LOONGSON3B_R1	0x0006
 #define PRID_REV_LOONGSON3B_R2	0x0007
 #define PRID_REV_LOONGSON3A_R2	0x0008
+#define PRID_REV_LOONGSON3A_R3	0x0009
 
 /*
  * Older processors used to encode processor version and revision in two
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 353ade2..09462bb 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -1836,6 +1836,12 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
 			set_elf_platform(cpu, "loongson3a");
 			set_isa(c, MIPS_CPU_ISA_M64R2);
 			break;
+		case PRID_REV_LOONGSON3A_R3:
+			c->cputype = CPU_LOONGSON3;
+			__cpu_name[cpu] = "ICT Loongson-3";
+			set_elf_platform(cpu, "loongson3a");
+			set_isa(c, MIPS_CPU_ISA_M64R2);
+			break;
 		}
 
 		decode_configs(c);
diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
index 6afa218..4707abf 100644
--- a/arch/mips/loongson64/common/env.c
+++ b/arch/mips/loongson64/common/env.c
@@ -193,6 +193,7 @@ void __init prom_init_env(void)
 			break;
 		case PRID_REV_LOONGSON3A_R1:
 		case PRID_REV_LOONGSON3A_R2:
+		case PRID_REV_LOONGSON3A_R3:
 			cpu_clock_freq = 900000000;
 			break;
 		case PRID_REV_LOONGSON3B_R1:
diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index 64659fc..1629743 100644
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -503,7 +503,7 @@ static void loongson3a_r1_play_dead(int *state_addr)
 		: "a1");
 }
 
-static void loongson3a_r2_play_dead(int *state_addr)
+static void loongson3a_r2r3_play_dead(int *state_addr)
 {
 	register int val;
 	register long cpuid, core, node, count;
@@ -664,8 +664,9 @@ void play_dead(void)
 			(void *)CKSEG1ADDR((unsigned long)loongson3a_r1_play_dead);
 		break;
 	case PRID_REV_LOONGSON3A_R2:
+	case PRID_REV_LOONGSON3A_R3:
 		play_dead_at_ckseg1 =
-			(void *)CKSEG1ADDR((unsigned long)loongson3a_r2_play_dead);
+			(void *)CKSEG1ADDR((unsigned long)loongson3a_r2r3_play_dead);
 		break;
 	case PRID_REV_LOONGSON3B_R1:
 	case PRID_REV_LOONGSON3B_R2:
diff --git a/drivers/platform/mips/cpu_hwmon.c b/drivers/platform/mips/cpu_hwmon.c
index 4300a55..46ab7d86 100644
--- a/drivers/platform/mips/cpu_hwmon.c
+++ b/drivers/platform/mips/cpu_hwmon.c
@@ -17,14 +17,23 @@
  */
 int loongson3_cpu_temp(int cpu)
 {
-	u32 reg;
+	u32 reg, prid_rev;
 
 	reg = LOONGSON_CHIPTEMP(cpu);
-	if ((read_c0_prid() & PRID_REV_MASK) == PRID_REV_LOONGSON3A_R1)
+	prid_rev = read_c0_prid() & PRID_REV_MASK;
+	switch (prid_rev) {
+	case PRID_REV_LOONGSON3A_R1:
 		reg = (reg >> 8) & 0xff;
-	else
+		break;
+	case PRID_REV_LOONGSON3A_R2:
+	case PRID_REV_LOONGSON3B_R1:
+	case PRID_REV_LOONGSON3B_R2:
 		reg = ((reg >> 8) & 0xff) - 100;
-
+		break;
+	case PRID_REV_LOONGSON3A_R3:
+		reg = (reg & 0xffff)*731/0x4000 - 273;
+		break;
+	}
 	return (int)reg * 1000;
 }
 
-- 
2.7.0

[PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[Huacai Chen]

For multi-node Loongson-3 (NUMA configuration), r4k_blast_scache() can
only flush Node-0's scache. So we add r4k_blast_scache_node() by using
(CAC_BASE | (node_id << NODE_ADDRSPACE_SHIFT)) instead of CKSEG0 as the
start address.

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/r4kcache.h | 30 ++++++++++++++++++++++++++++
 arch/mips/mm/c-r4k.c             | 42 +++++++++++++++++++++++++++++++++-------
 2 files changed, 65 insertions(+), 7 deletions(-)

diff --git a/arch/mips/include/asm/r4kcache.h b/arch/mips/include/asm/r4kcache.h
index 7f12d7e..e5ece81 100644
--- a/arch/mips/include/asm/r4kcache.h
+++ b/arch/mips/include/asm/r4kcache.h
@@ -747,4 +747,34 @@ __BUILD_BLAST_CACHE_RANGE(s, scache, Hit_Writeback_Inv_SD, , )
 __BUILD_BLAST_CACHE_RANGE(inv_d, dcache, Hit_Invalidate_D, , )
 __BUILD_BLAST_CACHE_RANGE(inv_s, scache, Hit_Invalidate_SD, , )
 
+#ifndef NODE_ADDRSPACE_SHIFT
+#define nid_to_addrbase(nid) 0
+#else
+#define nid_to_addrbase(nid) (nid << NODE_ADDRSPACE_SHIFT)
+#endif
+
+#define __BUILD_BLAST_CACHE_NODE(pfx, desc, indexop, hitop, lsize)	\
+static inline void blast_##pfx##cache##lsize##_node(long node)		\
+{									\
+	unsigned long start = CAC_BASE | nid_to_addrbase(node);		\
+	unsigned long end = start + current_cpu_data.desc.waysize;	\
+	unsigned long ws_inc = 1UL << current_cpu_data.desc.waybit;	\
+	unsigned long ws_end = current_cpu_data.desc.ways <<		\
+			       current_cpu_data.desc.waybit;		\
+	unsigned long ws, addr;						\
+									\
+	__##pfx##flush_prologue						\
+									\
+	for (ws = 0; ws < ws_end; ws += ws_inc)				\
+		for (addr = start; addr < end; addr += lsize * 32)	\
+			cache##lsize##_unroll32(addr|ws, indexop);	\
+									\
+	__##pfx##flush_epilogue						\
+}
+
+__BUILD_BLAST_CACHE_NODE(s, scache, Index_Writeback_Inv_SD, Hit_Writeback_Inv_SD, 16)
+__BUILD_BLAST_CACHE_NODE(s, scache, Index_Writeback_Inv_SD, Hit_Writeback_Inv_SD, 32)
+__BUILD_BLAST_CACHE_NODE(s, scache, Index_Writeback_Inv_SD, Hit_Writeback_Inv_SD, 64)
+__BUILD_BLAST_CACHE_NODE(s, scache, Index_Writeback_Inv_SD, Hit_Writeback_Inv_SD, 128)
+
 #endif /* _ASM_R4KCACHE_H */
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 81d6a15..7b242e8 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -459,11 +459,28 @@ static void r4k_blast_scache_setup(void)
 		r4k_blast_scache = blast_scache128;
 }
 
+static void (* r4k_blast_scache_node)(long node);
+
+static void r4k_blast_scache_node_setup(void)
+{
+	unsigned long sc_lsize = cpu_scache_line_size();
+
+	if (current_cpu_type() != CPU_LOONGSON3)
+		r4k_blast_scache_node = (void *)cache_noop;
+	else if (sc_lsize == 16)
+		r4k_blast_scache_node = blast_scache16_node;
+	else if (sc_lsize == 32)
+		r4k_blast_scache_node = blast_scache32_node;
+	else if (sc_lsize == 64)
+		r4k_blast_scache_node = blast_scache64_node;
+	else if (sc_lsize == 128)
+		r4k_blast_scache_node = blast_scache128_node;
+}
+
 static inline void local_r4k___flush_cache_all(void * args)
 {
 	switch (current_cpu_type()) {
 	case CPU_LOONGSON2:
-	case CPU_LOONGSON3:
 	case CPU_R4000SC:
 	case CPU_R4000MC:
 	case CPU_R4400SC:
@@ -480,6 +497,10 @@ static inline void local_r4k___flush_cache_all(void * args)
 		r4k_blast_scache();
 		break;
 
+	case CPU_LOONGSON3:
+		r4k_blast_scache_node(get_ebase_cpunum() >> 2);
+		break;
+
 	case CPU_BMIPS5000:
 		r4k_blast_scache();
 		__sync();
@@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
 
 	preempt_disable();
 	if (cpu_has_inclusive_pcaches) {
-		if (size >= scache_size)
-			r4k_blast_scache();
-		else
+		if (size >= scache_size) {
+			if (current_cpu_type() != CPU_LOONGSON3)
+				r4k_blast_scache();
+			else
+				r4k_blast_scache_node(pa_to_nid(addr));
+		} else
 			blast_scache_range(addr, addr + size);
 		preempt_enable();
 		__sync();
@@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
 
 	preempt_disable();
 	if (cpu_has_inclusive_pcaches) {
-		if (size >= scache_size)
-			r4k_blast_scache();
-		else {
+		if (size >= scache_size) {
+			if (current_cpu_type() != CPU_LOONGSON3)
+				r4k_blast_scache();
+			else
+				r4k_blast_scache_node(pa_to_nid(addr));
+		} else {
 			/*
 			 * There is no clearly documented alignment requirement
 			 * for the cache instruction on MIPS processors and
@@ -1905,6 +1932,7 @@ void r4k_cache_init(void)
 	r4k_blast_scache_page_setup();
 	r4k_blast_scache_page_indexed_setup();
 	r4k_blast_scache_setup();
+	r4k_blast_scache_node_setup();
 #ifdef CONFIG_EVA
 	r4k_blast_dcache_user_page_setup();
 	r4k_blast_icache_user_page_setup();
-- 
2.7.0

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[James Hogan]

[-- Attachment #1: Type: text/plain, Size: 1284 bytes --]

Hi Huacai,

On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
>  
>  	preempt_disable();
>  	if (cpu_has_inclusive_pcaches) {
> -		if (size >= scache_size)
> -			r4k_blast_scache();
> -		else
> +		if (size >= scache_size) {
> +			if (current_cpu_type() != CPU_LOONGSON3)
> +				r4k_blast_scache();
> +			else
> +				r4k_blast_scache_node(pa_to_nid(addr));
> +		} else
>  			blast_scache_range(addr, addr + size);
>  		preempt_enable();
>  		__sync();
> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
>  
>  	preempt_disable();
>  	if (cpu_has_inclusive_pcaches) {
> -		if (size >= scache_size)
> -			r4k_blast_scache();
> -		else {
> +		if (size >= scache_size) {
> +			if (current_cpu_type() != CPU_LOONGSON3)
> +				r4k_blast_scache();
> +			else
> +				r4k_blast_scache_node(pa_to_nid(addr));

malta_defconfig now fails to build:

arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function ‘pa_to_nid’ [-Werror=implicit-function-declaration]
     r4k_blast_scache_node(pa_to_nid(addr));
     ^

Cheers
James

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Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[James Hogan]

[-- Attachment #1: Type: text/plain, Size: 1284 bytes --]

Hi Huacai,

On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
>  
>  	preempt_disable();
>  	if (cpu_has_inclusive_pcaches) {
> -		if (size >= scache_size)
> -			r4k_blast_scache();
> -		else
> +		if (size >= scache_size) {
> +			if (current_cpu_type() != CPU_LOONGSON3)
> +				r4k_blast_scache();
> +			else
> +				r4k_blast_scache_node(pa_to_nid(addr));
> +		} else
>  			blast_scache_range(addr, addr + size);
>  		preempt_enable();
>  		__sync();
> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
>  
>  	preempt_disable();
>  	if (cpu_has_inclusive_pcaches) {
> -		if (size >= scache_size)
> -			r4k_blast_scache();
> -		else {
> +		if (size >= scache_size) {
> +			if (current_cpu_type() != CPU_LOONGSON3)
> +				r4k_blast_scache();
> +			else
> +				r4k_blast_scache_node(pa_to_nid(addr));

malta_defconfig now fails to build:

arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function ‘pa_to_nid’ [-Werror=implicit-function-declaration]
     r4k_blast_scache_node(pa_to_nid(addr));
     ^

Cheers
James

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Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[Huacai Chen]

Hi, James,

Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
#define pa_to_nid(addr) 0

Huacai

On Wed, Jun 28, 2017 at 10:30 PM, James Hogan <james.hogan@imgtec.com> wrote:
> Hi Huacai,
>
> On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
>> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
>>
>>       preempt_disable();
>>       if (cpu_has_inclusive_pcaches) {
>> -             if (size >= scache_size)
>> -                     r4k_blast_scache();
>> -             else
>> +             if (size >= scache_size) {
>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>> +                             r4k_blast_scache();
>> +                     else
>> +                             r4k_blast_scache_node(pa_to_nid(addr));
>> +             } else
>>                       blast_scache_range(addr, addr + size);
>>               preempt_enable();
>>               __sync();
>> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
>>
>>       preempt_disable();
>>       if (cpu_has_inclusive_pcaches) {
>> -             if (size >= scache_size)
>> -                     r4k_blast_scache();
>> -             else {
>> +             if (size >= scache_size) {
>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>> +                             r4k_blast_scache();
>> +                     else
>> +                             r4k_blast_scache_node(pa_to_nid(addr));
>
> malta_defconfig now fails to build:
>
> arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
> arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function ‘pa_to_nid’ [-Werror=implicit-function-declaration]
>      r4k_blast_scache_node(pa_to_nid(addr));
>      ^
>
> Cheers
> James

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[James Hogan]

On 29 June 2017 02:33:28 BST, Huacai Chen <chenhc@lemote.com> wrote:
>Hi, James,
>
>Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
>#define pa_to_nid(addr) 0

It was basically malta_defconfig.

OTOH when i tried including asm/mmzone.h, that tries including <mmzone.h> which it can't find.

Cheers
Jamee

>
>Huacai
>
>On Wed, Jun 28, 2017 at 10:30 PM, James Hogan <james.hogan@imgtec.com>
>wrote:
>> Hi Huacai,
>>
>> On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
>>> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned
>long addr, unsigned long size)
>>>
>>>       preempt_disable();
>>>       if (cpu_has_inclusive_pcaches) {
>>> -             if (size >= scache_size)
>>> -                     r4k_blast_scache();
>>> -             else
>>> +             if (size >= scache_size) {
>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>> +                             r4k_blast_scache();
>>> +                     else
>>> +                            
>r4k_blast_scache_node(pa_to_nid(addr));
>>> +             } else
>>>                       blast_scache_range(addr, addr + size);
>>>               preempt_enable();
>>>               __sync();
>>> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long
>addr, unsigned long size)
>>>
>>>       preempt_disable();
>>>       if (cpu_has_inclusive_pcaches) {
>>> -             if (size >= scache_size)
>>> -                     r4k_blast_scache();
>>> -             else {
>>> +             if (size >= scache_size) {
>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>> +                             r4k_blast_scache();
>>> +                     else
>>> +                            
>r4k_blast_scache_node(pa_to_nid(addr));
>>
>> malta_defconfig now fails to build:
>>
>> arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
>> arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function
>‘pa_to_nid’ [-Werror=implicit-function-declaration]
>>      r4k_blast_scache_node(pa_to_nid(addr));
>>      ^
>>
>> Cheers
>> James


--
James Hogan

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[James Hogan]

On 29 June 2017 02:33:28 BST, Huacai Chen <chenhc@lemote.com> wrote:
>Hi, James,
>
>Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
>#define pa_to_nid(addr) 0

It was basically malta_defconfig.

OTOH when i tried including asm/mmzone.h, that tries including <mmzone.h> which it can't find.

Cheers
Jamee

>
>Huacai
>
>On Wed, Jun 28, 2017 at 10:30 PM, James Hogan <james.hogan@imgtec.com>
>wrote:
>> Hi Huacai,
>>
>> On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
>>> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned
>long addr, unsigned long size)
>>>
>>>       preempt_disable();
>>>       if (cpu_has_inclusive_pcaches) {
>>> -             if (size >= scache_size)
>>> -                     r4k_blast_scache();
>>> -             else
>>> +             if (size >= scache_size) {
>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>> +                             r4k_blast_scache();
>>> +                     else
>>> +                            
>r4k_blast_scache_node(pa_to_nid(addr));
>>> +             } else
>>>                       blast_scache_range(addr, addr + size);
>>>               preempt_enable();
>>>               __sync();
>>> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long
>addr, unsigned long size)
>>>
>>>       preempt_disable();
>>>       if (cpu_has_inclusive_pcaches) {
>>> -             if (size >= scache_size)
>>> -                     r4k_blast_scache();
>>> -             else {
>>> +             if (size >= scache_size) {
>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>> +                             r4k_blast_scache();
>>> +                     else
>>> +                            
>r4k_blast_scache_node(pa_to_nid(addr));
>>
>> malta_defconfig now fails to build:
>>
>> arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
>> arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function
>‘pa_to_nid’ [-Werror=implicit-function-declaration]
>>      r4k_blast_scache_node(pa_to_nid(addr));
>>      ^
>>
>> Cheers
>> James


--
James Hogan

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[Huacai Chen]

Create arch/mips/include/asm/mach-malta/mmzone.h and put this line in it?
#define pa_to_nid(addr) 0

Huacai

On Thu, Jun 29, 2017 at 1:46 PM, James Hogan <james.hogan@imgtec.com> wrote:
> On 29 June 2017 02:33:28 BST, Huacai Chen <chenhc@lemote.com> wrote:
>>Hi, James,
>>
>>Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
>>#define pa_to_nid(addr) 0
>
> It was basically malta_defconfig.
>
> OTOH when i tried including asm/mmzone.h, that tries including <mmzone.h> which it can't find.
>
> Cheers
> Jamee
>
>>
>>Huacai
>>
>>On Wed, Jun 28, 2017 at 10:30 PM, James Hogan <james.hogan@imgtec.com>
>>wrote:
>>> Hi Huacai,
>>>
>>> On Thu, Jun 22, 2017 at 11:06:49PM +0800, Huacai Chen wrote:
>>>> @@ -839,9 +860,12 @@ static void r4k_dma_cache_wback_inv(unsigned
>>long addr, unsigned long size)
>>>>
>>>>       preempt_disable();
>>>>       if (cpu_has_inclusive_pcaches) {
>>>> -             if (size >= scache_size)
>>>> -                     r4k_blast_scache();
>>>> -             else
>>>> +             if (size >= scache_size) {
>>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>>> +                             r4k_blast_scache();
>>>> +                     else
>>>> +
>>r4k_blast_scache_node(pa_to_nid(addr));
>>>> +             } else
>>>>                       blast_scache_range(addr, addr + size);
>>>>               preempt_enable();
>>>>               __sync();
>>>> @@ -872,9 +896,12 @@ static void r4k_dma_cache_inv(unsigned long
>>addr, unsigned long size)
>>>>
>>>>       preempt_disable();
>>>>       if (cpu_has_inclusive_pcaches) {
>>>> -             if (size >= scache_size)
>>>> -                     r4k_blast_scache();
>>>> -             else {
>>>> +             if (size >= scache_size) {
>>>> +                     if (current_cpu_type() != CPU_LOONGSON3)
>>>> +                             r4k_blast_scache();
>>>> +                     else
>>>> +
>>r4k_blast_scache_node(pa_to_nid(addr));
>>>
>>> malta_defconfig now fails to build:
>>>
>>> arch/mips/mm/c-r4k.c: In function ‘r4k_dma_cache_wback_inv’:
>>> arch/mips/mm/c-r4k.c:867:5: error: implicit declaration of function
>>‘pa_to_nid’ [-Werror=implicit-function-declaration]
>>>      r4k_blast_scache_node(pa_to_nid(addr));
>>>      ^
>>>
>>> Cheers
>>> James
>
>
> --
> James Hogan
>

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[Joshua Kinard]

On 06/29/2017 01:46, James Hogan wrote:
> On 29 June 2017 02:33:28 BST, Huacai Chen <chenhc@lemote.com> wrote:
>> Hi, James,
>>
>> Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
>> #define pa_to_nid(addr) 0
> 
> It was basically malta_defconfig.
> 
> OTOH when i tried including asm/mmzone.h, that tries including <mmzone.h> which it can't find.
> 
> Cheers
> Jamee
> 

<asm/mmzone.h> is only supposed to be defined for NUMA-aware systems, as far as
I can tell.  I believe a lot of the Loongson code derives somewhat from the
IP27 code, as both are the only MIPS platforms that define a specific version
of that header.

It also looks like the generic mmzone.h header probably just needs the
<mmzone.h> include removed.  pa_to_nid is only used for pfn_to_nid when
CONFIG_DISCONTIGMEM is set, and IP27 is one of the only platforms that uses
that memory model.

--J

Re: [PATCH V7 2/9] MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3

[Huacai Chen]

What about add these lines in c-r4k.c?
#ifnde pa_to_nid
#define pa_to_nid(addr) 0
#endif

Huacai

On Thu, Jun 29, 2017 at 6:23 PM, Joshua Kinard <kumba@gentoo.org> wrote:
> On 06/29/2017 01:46, James Hogan wrote:
>> On 29 June 2017 02:33:28 BST, Huacai Chen <chenhc@lemote.com> wrote:
>>> Hi, James,
>>>
>>> Is it suitable to add this line in arch/mips/include/asm/mmzone.h?
>>> #define pa_to_nid(addr) 0
>>
>> It was basically malta_defconfig.
>>
>> OTOH when i tried including asm/mmzone.h, that tries including <mmzone.h> which it can't find.
>>
>> Cheers
>> Jamee
>>
>
> <asm/mmzone.h> is only supposed to be defined for NUMA-aware systems, as far as
> I can tell.  I believe a lot of the Loongson code derives somewhat from the
> IP27 code, as both are the only MIPS platforms that define a specific version
> of that header.
>
> It also looks like the generic mmzone.h header probably just needs the
> <mmzone.h> include removed.  pa_to_nid is only used for pfn_to_nid when
> CONFIG_DISCONTIGMEM is set, and IP27 is one of the only platforms that uses
> that memory model.
>
> --J
>

[PATCH V7 3/9] MIPS: Loongson: Add NMI handler support

[Huacai Chen]

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/common/init.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/mips/loongson64/common/init.c b/arch/mips/loongson64/common/init.c
index 9b987fe..6ef1712 100644
--- a/arch/mips/loongson64/common/init.c
+++ b/arch/mips/loongson64/common/init.c
@@ -10,13 +10,25 @@
 
 #include <linux/bootmem.h>
 #include <asm/bootinfo.h>
+#include <asm/traps.h>
 #include <asm/smp-ops.h>
+#include <asm/cacheflush.h>
 
 #include <loongson.h>
 
 /* Loongson CPU address windows config space base address */
 unsigned long __maybe_unused _loongson_addrwincfg_base;
 
+static void __init mips_nmi_setup(void)
+{
+	void *base;
+	extern char except_vec_nmi;
+
+	base = (void *)(CAC_BASE + 0x380);
+	memcpy(base, &except_vec_nmi, 0x80);
+	flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
+}
+
 void __init prom_init(void)
 {
 #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
@@ -40,6 +52,7 @@ void __init prom_init(void)
 	/*init the uart base address */
 	prom_init_uart_base();
 	register_smp_ops(&loongson3_smp_ops);
+	board_nmi_handler_setup = mips_nmi_setup;
 }
 
 void __init prom_free_prom_memory(void)
-- 
2.7.0

[PATCH V7 4/9] MIPS: Loongson-3: Support 4 packages in CPU Hwmon driver

[Huacai Chen]

Loongson-3 machines may have as many as 4 physical packages.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 drivers/platform/mips/cpu_hwmon.c | 119 +++++++++++++++++++-------------------
 1 file changed, 58 insertions(+), 61 deletions(-)

diff --git a/drivers/platform/mips/cpu_hwmon.c b/drivers/platform/mips/cpu_hwmon.c
index 46ab7d86..322de58 100644
--- a/drivers/platform/mips/cpu_hwmon.c
+++ b/drivers/platform/mips/cpu_hwmon.c
@@ -37,6 +37,7 @@ int loongson3_cpu_temp(int cpu)
 	return (int)reg * 1000;
 }
 
+static int nr_packages;
 static struct device *cpu_hwmon_dev;
 
 static ssize_t get_hwmon_name(struct device *dev,
@@ -60,88 +61,74 @@ static ssize_t get_hwmon_name(struct device *dev,
 	return sprintf(buf, "cpu-hwmon\n");
 }
 
-static ssize_t get_cpu0_temp(struct device *dev,
+static ssize_t get_cpu_temp(struct device *dev,
 			struct device_attribute *attr, char *buf);
-static ssize_t get_cpu1_temp(struct device *dev,
-			struct device_attribute *attr, char *buf);
-static ssize_t cpu0_temp_label(struct device *dev,
-			struct device_attribute *attr, char *buf);
-static ssize_t cpu1_temp_label(struct device *dev,
+static ssize_t cpu_temp_label(struct device *dev,
 			struct device_attribute *attr, char *buf);
 
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu0_temp, NULL, 1);
-static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu0_temp_label, NULL, 1);
-static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu1_temp, NULL, 2);
-static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu1_temp_label, NULL, 2);
-
-static const struct attribute *hwmon_cputemp1[] = {
-	&sensor_dev_attr_temp1_input.dev_attr.attr,
-	&sensor_dev_attr_temp1_label.dev_attr.attr,
-	NULL
-};
-
-static const struct attribute *hwmon_cputemp2[] = {
-	&sensor_dev_attr_temp2_input.dev_attr.attr,
-	&sensor_dev_attr_temp2_label.dev_attr.attr,
-	NULL
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4);
+static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4);
+
+static const struct attribute *hwmon_cputemp[4][3] = {
+	{
+		&sensor_dev_attr_temp1_input.dev_attr.attr,
+		&sensor_dev_attr_temp1_label.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_temp2_input.dev_attr.attr,
+		&sensor_dev_attr_temp2_label.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_temp3_input.dev_attr.attr,
+		&sensor_dev_attr_temp3_label.dev_attr.attr,
+		NULL
+	},
+	{
+		&sensor_dev_attr_temp4_input.dev_attr.attr,
+		&sensor_dev_attr_temp4_label.dev_attr.attr,
+		NULL
+	}
 };
 
-static ssize_t cpu0_temp_label(struct device *dev,
+static ssize_t cpu_temp_label(struct device *dev,
 			struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "CPU 0 Temperature\n");
+	int id = (to_sensor_dev_attr(attr))->index - 1;
+	return sprintf(buf, "CPU %d Temperature\n", id);
 }
 
-static ssize_t cpu1_temp_label(struct device *dev,
+static ssize_t get_cpu_temp(struct device *dev,
 			struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "CPU 1 Temperature\n");
-}
-
-static ssize_t get_cpu0_temp(struct device *dev,
-			struct device_attribute *attr, char *buf)
-{
-	int value = loongson3_cpu_temp(0);
-	return sprintf(buf, "%d\n", value);
-}
-
-static ssize_t get_cpu1_temp(struct device *dev,
-			struct device_attribute *attr, char *buf)
-{
-	int value = loongson3_cpu_temp(1);
+	int id = (to_sensor_dev_attr(attr))->index - 1;
+	int value = loongson3_cpu_temp(id);
 	return sprintf(buf, "%d\n", value);
 }
 
 static int create_sysfs_cputemp_files(struct kobject *kobj)
 {
-	int ret;
-
-	ret = sysfs_create_files(kobj, hwmon_cputemp1);
-	if (ret)
-		goto sysfs_create_temp1_fail;
-
-	if (loongson_sysconf.nr_cpus <= loongson_sysconf.cores_per_package)
-		return 0;
-
-	ret = sysfs_create_files(kobj, hwmon_cputemp2);
-	if (ret)
-		goto sysfs_create_temp2_fail;
+	int i, ret = 0;
 
-	return 0;
+	for (i=0; i<nr_packages; i++)
+		ret = sysfs_create_files(kobj, hwmon_cputemp[i]);
 
-sysfs_create_temp2_fail:
-	sysfs_remove_files(kobj, hwmon_cputemp1);
-
-sysfs_create_temp1_fail:
-	return -1;
+	return ret;
 }
 
 static void remove_sysfs_cputemp_files(struct kobject *kobj)
 {
-	sysfs_remove_files(&cpu_hwmon_dev->kobj, hwmon_cputemp1);
+	int i;
 
-	if (loongson_sysconf.nr_cpus > loongson_sysconf.cores_per_package)
-		sysfs_remove_files(&cpu_hwmon_dev->kobj, hwmon_cputemp2);
+	for (i=0; i<nr_packages; i++)
+		sysfs_remove_files(kobj, hwmon_cputemp[i]);
 }
 
 #define CPU_THERMAL_THRESHOLD 90000
@@ -149,8 +136,15 @@ static struct delayed_work thermal_work;
 
 static void do_thermal_timer(struct work_struct *work)
 {
-	int value = loongson3_cpu_temp(0);
-	if (value <= CPU_THERMAL_THRESHOLD)
+	int i, value, temp_max = 0;
+
+	for (i=0; i<nr_packages; i++) {
+		value = loongson3_cpu_temp(i);
+		if (value > temp_max)
+			temp_max = value;
+	}
+
+	if (temp_max <= CPU_THERMAL_THRESHOLD)
 		schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
 	else
 		orderly_poweroff(true);
@@ -169,6 +163,9 @@ static int __init loongson_hwmon_init(void)
 		goto fail_hwmon_device_register;
 	}
 
+	nr_packages = loongson_sysconf.nr_cpus /
+		loongson_sysconf.cores_per_package;
+
 	ret = sysfs_create_group(&cpu_hwmon_dev->kobj,
 				&cpu_hwmon_attribute_group);
 	if (ret) {
-- 
2.7.0

[PATCH V7 5/9] MIPS: Loongson-3: IRQ balancing for PCI devices

[Huacai Chen]

IRQ0 (HPET), IRQ1 (Keyboard), IRQ2 (Cascade), IRQ7 (SCI), IRQ8 (RTC)
and IRQ12 (Mouse) are handled by core-0 locally. Other PCI IRQs (3, 4,
5, 6, 14, 15) are balanced by all cores from Node-0. This can improve
I/O performance significantly.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/irq.c | 19 +++++++++++++++++--
 arch/mips/loongson64/loongson-3/smp.c | 18 +++++++++++++++++-
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/arch/mips/loongson64/loongson-3/irq.c b/arch/mips/loongson64/loongson-3/irq.c
index 548f759..2e6e205 100644
--- a/arch/mips/loongson64/loongson-3/irq.c
+++ b/arch/mips/loongson64/loongson-3/irq.c
@@ -9,17 +9,32 @@
 
 #include "smp.h"
 
+extern void loongson3_send_irq_by_ipi(int cpu, int irqs);
 unsigned int ht_irq[] = {0, 1, 3, 4, 5, 6, 7, 8, 12, 14, 15};
+unsigned int local_irq = 1<<0 | 1<<1 | 1<<2 | 1<<7 | 1<<8 | 1<<12;
 
 static void ht_irqdispatch(void)
 {
-	unsigned int i, irq;
+	unsigned int i, irq, irq0, irq1;
+	static unsigned int dest_cpu = 0;
 
 	irq = LOONGSON_HT1_INT_VECTOR(0);
 	LOONGSON_HT1_INT_VECTOR(0) = irq; /* Acknowledge the IRQs */
 
+	irq0 = irq & local_irq;  /* handled by local core */
+	irq1 = irq & ~local_irq; /* balanced by other cores */
+
+	if (dest_cpu == 0 || !cpu_online(dest_cpu))
+		irq0 |= irq1;
+	else
+		loongson3_send_irq_by_ipi(dest_cpu, irq1);
+
+	dest_cpu = dest_cpu + 1;
+	if (dest_cpu >= num_possible_cpus() || cpu_data[dest_cpu].package > 0)
+		dest_cpu = 0;
+
 	for (i = 0; i < ARRAY_SIZE(ht_irq); i++) {
-		if (irq & (0x1 << ht_irq[i]))
+		if (irq0 & (0x1 << ht_irq[i]))
 			do_IRQ(ht_irq[i]);
 	}
 }
diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index 1629743..b7a355c 100644
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -254,13 +254,21 @@ loongson3_send_ipi_mask(const struct cpumask *mask, unsigned int action)
 		loongson3_ipi_write32((u32)action, ipi_set0_regs[cpu_logical_map(i)]);
 }
 
+#define IPI_IRQ_OFFSET 6
+
+void loongson3_send_irq_by_ipi(int cpu, int irqs)
+{
+	loongson3_ipi_write32(irqs << IPI_IRQ_OFFSET, ipi_set0_regs[cpu_logical_map(cpu)]);
+}
+
 void loongson3_ipi_interrupt(struct pt_regs *regs)
 {
 	int i, cpu = smp_processor_id();
-	unsigned int action, c0count;
+	unsigned int action, c0count, irqs;
 
 	/* Load the ipi register to figure out what we're supposed to do */
 	action = loongson3_ipi_read32(ipi_status0_regs[cpu_logical_map(cpu)]);
+	irqs = action >> IPI_IRQ_OFFSET;
 
 	/* Clear the ipi register to clear the interrupt */
 	loongson3_ipi_write32((u32)action, ipi_clear0_regs[cpu_logical_map(cpu)]);
@@ -282,6 +290,14 @@ void loongson3_ipi_interrupt(struct pt_regs *regs)
 			core0_c0count[i] = c0count;
 		__wbflush(); /* Let others see the result ASAP */
 	}
+
+	if (irqs) {
+		int irq;
+		while ((irq = ffs(irqs))) {
+			do_IRQ(irq-1);
+			irqs &= ~(1<<(irq-1));
+		}
+	}
 }
 
 #define MAX_LOOPS 800
-- 
2.7.0

[PATCH V7 6/9] MIPS: Loongson-3: support irq_set_affinity() in i8259 chip

[Huacai Chen]

With this patch we can set irq affinity via procfs, so as to improve
network performance.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/loongson64/loongson-3/irq.c | 67 ++++++++++++++++++++++++++++-------
 1 file changed, 54 insertions(+), 13 deletions(-)

diff --git a/arch/mips/loongson64/loongson-3/irq.c b/arch/mips/loongson64/loongson-3/irq.c
index 2e6e205..7202e52 100644
--- a/arch/mips/loongson64/loongson-3/irq.c
+++ b/arch/mips/loongson64/loongson-3/irq.c
@@ -10,32 +10,68 @@
 #include "smp.h"
 
 extern void loongson3_send_irq_by_ipi(int cpu, int irqs);
+
+unsigned int irq_cpu[16] = {[0 ... 15] = -1};
 unsigned int ht_irq[] = {0, 1, 3, 4, 5, 6, 7, 8, 12, 14, 15};
 unsigned int local_irq = 1<<0 | 1<<1 | 1<<2 | 1<<7 | 1<<8 | 1<<12;
 
+int plat_set_irq_affinity(struct irq_data *d, const struct cpumask *affinity,
+			  bool force)
+{
+	unsigned int cpu;
+	struct cpumask new_affinity;
+
+	/* I/O devices are connected on package-0 */
+	cpumask_copy(&new_affinity, affinity);
+	for_each_cpu(cpu, affinity)
+		if (cpu_data[cpu].package > 0)
+			cpumask_clear_cpu(cpu, &new_affinity);
+
+	if (cpumask_empty(&new_affinity))
+		return -EINVAL;
+
+	cpumask_copy(d->common->affinity, &new_affinity);
+
+	return IRQ_SET_MASK_OK_NOCOPY;
+}
+
 static void ht_irqdispatch(void)
 {
-	unsigned int i, irq, irq0, irq1;
-	static unsigned int dest_cpu = 0;
+	unsigned int i, irq;
+	struct irq_data *irqd;
+	struct cpumask affinity;
 
 	irq = LOONGSON_HT1_INT_VECTOR(0);
 	LOONGSON_HT1_INT_VECTOR(0) = irq; /* Acknowledge the IRQs */
 
-	irq0 = irq & local_irq;  /* handled by local core */
-	irq1 = irq & ~local_irq; /* balanced by other cores */
+	for (i = 0; i < ARRAY_SIZE(ht_irq); i++) {
+		if (!(irq & (0x1 << ht_irq[i])))
+			continue;
 
-	if (dest_cpu == 0 || !cpu_online(dest_cpu))
-		irq0 |= irq1;
-	else
-		loongson3_send_irq_by_ipi(dest_cpu, irq1);
+		/* handled by local core */
+		if (local_irq & (0x1 << ht_irq[i])) {
+			do_IRQ(ht_irq[i]);
+			continue;
+		}
 
-	dest_cpu = dest_cpu + 1;
-	if (dest_cpu >= num_possible_cpus() || cpu_data[dest_cpu].package > 0)
-		dest_cpu = 0;
+		irqd = irq_get_irq_data(ht_irq[i]);
+		cpumask_and(&affinity, irqd->common->affinity, cpu_active_mask);
+		if (cpumask_empty(&affinity)) {
+			do_IRQ(ht_irq[i]);
+			continue;
+		}
 
-	for (i = 0; i < ARRAY_SIZE(ht_irq); i++) {
-		if (irq0 & (0x1 << ht_irq[i]))
+		irq_cpu[ht_irq[i]] = cpumask_next(irq_cpu[ht_irq[i]], &affinity);
+		if (irq_cpu[ht_irq[i]] >= nr_cpu_ids)
+			irq_cpu[ht_irq[i]] = cpumask_first(&affinity);
+
+		if (irq_cpu[ht_irq[i]] == 0) {
 			do_IRQ(ht_irq[i]);
+			continue;
+		}
+
+		/* balanced by other cores */
+		loongson3_send_irq_by_ipi(irq_cpu[ht_irq[i]], (0x1 << ht_irq[i]));
 	}
 }
 
@@ -135,11 +171,16 @@ void irq_router_init(void)
 
 void __init mach_init_irq(void)
 {
+	struct irq_chip *chip;
+
 	clear_c0_status(ST0_IM | ST0_BEV);
 
 	irq_router_init();
 	mips_cpu_irq_init();
 	init_i8259_irqs();
+	chip = irq_get_chip(I8259A_IRQ_BASE);
+	chip->irq_set_affinity = plat_set_irq_affinity;
+
 	irq_set_chip_and_handler(LOONGSON_UART_IRQ,
 			&loongson_irq_chip, handle_level_irq);
 
-- 
2.7.0

[PATCH V7 7/9] MIPS: Loogson: Make enum loongson_cpu_type more clear

[Huacai Chen]

Sort enum loongson_cpu_type in a more reasonable manner, this makes the
CPU names more clear and extensible. Those already defined enum values
are renamed to Legacy_* for compatibility.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/mach-loongson64/boot_param.h | 22 ++++++++++++++++------
 arch/mips/loongson64/common/env.c                  | 11 ++++++++---
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/arch/mips/include/asm/mach-loongson64/boot_param.h b/arch/mips/include/asm/mach-loongson64/boot_param.h
index d3f3258..9f9bb9c 100644
--- a/arch/mips/include/asm/mach-loongson64/boot_param.h
+++ b/arch/mips/include/asm/mach-loongson64/boot_param.h
@@ -27,12 +27,22 @@ struct efi_memory_map_loongson {
 } __packed;
 
 enum loongson_cpu_type {
-	Loongson_2E = 0,
-	Loongson_2F = 1,
-	Loongson_3A = 2,
-	Loongson_3B = 3,
-	Loongson_1A = 4,
-	Loongson_1B = 5
+	Legacy_2E = 0x0,
+	Legacy_2F = 0x1,
+	Legacy_3A = 0x2,
+	Legacy_3B = 0x3,
+	Legacy_1A = 0x4,
+	Legacy_1B = 0x5,
+	Legacy_2G = 0x6,
+	Legacy_2H = 0x7,
+	Loongson_1A = 0x100,
+	Loongson_1B = 0x101,
+	Loongson_2E = 0x200,
+	Loongson_2F = 0x201,
+	Loongson_2G = 0x202,
+	Loongson_2H = 0x203,
+	Loongson_3A = 0x300,
+	Loongson_3B = 0x301
 };
 
 /*
diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
index 4707abf..1e8a955 100644
--- a/arch/mips/loongson64/common/env.c
+++ b/arch/mips/loongson64/common/env.c
@@ -90,7 +90,9 @@ void __init prom_init_env(void)
 
 	cpu_clock_freq = ecpu->cpu_clock_freq;
 	loongson_sysconf.cputype = ecpu->cputype;
-	if (ecpu->cputype == Loongson_3A) {
+	switch (ecpu->cputype) {
+	case Legacy_3A:
+	case Loongson_3A:
 		loongson_sysconf.cores_per_node = 4;
 		loongson_sysconf.cores_per_package = 4;
 		smp_group[0] = 0x900000003ff01000;
@@ -111,7 +113,9 @@ void __init prom_init_env(void)
 		loongson_freqctrl[3] = 0x900030001fe001d0;
 		loongson_sysconf.ht_control_base = 0x90000EFDFB000000;
 		loongson_sysconf.workarounds = WORKAROUND_CPUFREQ;
-	} else if (ecpu->cputype == Loongson_3B) {
+		break;
+	case Legacy_3B:
+	case Loongson_3B:
 		loongson_sysconf.cores_per_node = 4; /* One chip has 2 nodes */
 		loongson_sysconf.cores_per_package = 8;
 		smp_group[0] = 0x900000003ff01000;
@@ -132,7 +136,8 @@ void __init prom_init_env(void)
 		loongson_freqctrl[3] = 0x900060001fe001d0;
 		loongson_sysconf.ht_control_base = 0x90001EFDFB000000;
 		loongson_sysconf.workarounds = WORKAROUND_CPUHOTPLUG;
-	} else {
+		break;
+	default:
 		loongson_sysconf.cores_per_node = 1;
 		loongson_sysconf.cores_per_package = 1;
 		loongson_chipcfg[0] = 0x900000001fe00180;
-- 
2.7.0

[PATCH V7 8/9] MIPS: Add __cpu_full_name[] to make CPU names more human-readable

[Huacai Chen]

In /proc/cpuinfo, we keep "cpu model" as is, since GCC should use it
for -march=native. Besides, we add __cpu_full_name[] to describe the
processor in a more human-readable manner. The full name is displayed
as "model name" in cpuinfo, which is needed by some userspace tools
such as gnome-system-monitor.

This is only used by Loongson now (ICT is dropped in cpu name, and cpu
name can be overwritten by BIOS).

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/cpu-info.h                   |  2 ++
 arch/mips/include/asm/mach-loongson64/boot_param.h |  1 +
 arch/mips/kernel/cpu-probe.c                       | 25 ++++++++++++++++------
 arch/mips/kernel/proc.c                            |  4 ++++
 arch/mips/loongson64/common/env.c                  | 18 ++++++++++++++++
 5 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/arch/mips/include/asm/cpu-info.h b/arch/mips/include/asm/cpu-info.h
index cd6efb0..8a8a414 100644
--- a/arch/mips/include/asm/cpu-info.h
+++ b/arch/mips/include/asm/cpu-info.h
@@ -121,7 +121,9 @@ extern void cpu_probe(void);
 extern void cpu_report(void);
 
 extern const char *__cpu_name[];
+extern const char *__cpu_full_name[];
 #define cpu_name_string()	__cpu_name[raw_smp_processor_id()]
+#define cpu_full_name_string()	__cpu_full_name[raw_smp_processor_id()]
 
 struct seq_file;
 struct notifier_block;
diff --git a/arch/mips/include/asm/mach-loongson64/boot_param.h b/arch/mips/include/asm/mach-loongson64/boot_param.h
index 9f9bb9c..b7ed31b 100644
--- a/arch/mips/include/asm/mach-loongson64/boot_param.h
+++ b/arch/mips/include/asm/mach-loongson64/boot_param.h
@@ -57,6 +57,7 @@ struct efi_cpuinfo_loongson {
 	u16 reserved_cores_mask;
 	u32 cpu_clock_freq; /* cpu_clock */
 	u32 nr_cpus;
+	char cpuname[64];
 } __packed;
 
 #define MAX_UARTS 64
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 09462bb..e1df437 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -1474,30 +1474,40 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 		switch (c->processor_id & PRID_REV_MASK) {
 		case PRID_REV_LOONGSON2E:
 			c->cputype = CPU_LOONGSON2;
-			__cpu_name[cpu] = "ICT Loongson-2";
+			__cpu_name[cpu] = "Loongson-2";
 			set_elf_platform(cpu, "loongson2e");
 			set_isa(c, MIPS_CPU_ISA_III);
 			c->fpu_msk31 |= FPU_CSR_CONDX;
+			__cpu_full_name[cpu] = "Loongson-2E";
 			break;
 		case PRID_REV_LOONGSON2F:
 			c->cputype = CPU_LOONGSON2;
-			__cpu_name[cpu] = "ICT Loongson-2";
+			__cpu_name[cpu] = "Loongson-2";
 			set_elf_platform(cpu, "loongson2f");
 			set_isa(c, MIPS_CPU_ISA_III);
 			c->fpu_msk31 |= FPU_CSR_CONDX;
+			__cpu_full_name[cpu] = "Loongson-2F";
 			break;
 		case PRID_REV_LOONGSON3A_R1:
 			c->cputype = CPU_LOONGSON3;
-			__cpu_name[cpu] = "ICT Loongson-3";
+			__cpu_name[cpu] = "Loongson-3";
 			set_elf_platform(cpu, "loongson3a");
 			set_isa(c, MIPS_CPU_ISA_M64R1);
+			__cpu_full_name[cpu] = "Loongson-3A R1 (Loongson-3A1000)";
 			break;
 		case PRID_REV_LOONGSON3B_R1:
+			c->cputype = CPU_LOONGSON3;
+			__cpu_name[cpu] = "Loongson-3";
+			set_elf_platform(cpu, "loongson3b");
+			set_isa(c, MIPS_CPU_ISA_M64R1);
+			__cpu_full_name[cpu] = "Loongson-3B R1 (Loongson-3B1000)";
+			break;
 		case PRID_REV_LOONGSON3B_R2:
 			c->cputype = CPU_LOONGSON3;
-			__cpu_name[cpu] = "ICT Loongson-3";
+			__cpu_name[cpu] = "Loongson-3";
 			set_elf_platform(cpu, "loongson3b");
 			set_isa(c, MIPS_CPU_ISA_M64R1);
+			__cpu_full_name[cpu] = "Loongson-3B R2 (Loongson-3B1500)";
 			break;
 		}
 
@@ -1832,15 +1842,17 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
 		switch (c->processor_id & PRID_REV_MASK) {
 		case PRID_REV_LOONGSON3A_R2:
 			c->cputype = CPU_LOONGSON3;
-			__cpu_name[cpu] = "ICT Loongson-3";
+			__cpu_name[cpu] = "Loongson-3";
 			set_elf_platform(cpu, "loongson3a");
 			set_isa(c, MIPS_CPU_ISA_M64R2);
+			__cpu_full_name[cpu] = "Loongson-3A R2 (Loongson-3A2000)";
 			break;
 		case PRID_REV_LOONGSON3A_R3:
 			c->cputype = CPU_LOONGSON3;
-			__cpu_name[cpu] = "ICT Loongson-3";
+			__cpu_name[cpu] = "Loongson-3";
 			set_elf_platform(cpu, "loongson3a");
 			set_isa(c, MIPS_CPU_ISA_M64R2);
+			__cpu_full_name[cpu] = "Loongson-3A R3 (Loongson-3A3000)";
 			break;
 		}
 
@@ -1960,6 +1972,7 @@ EXPORT_SYMBOL(__ua_limit);
 #endif
 
 const char *__cpu_name[NR_CPUS];
+const char *__cpu_full_name[NR_CPUS];
 const char *__elf_platform;
 
 void cpu_probe(void)
diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
index 4eff2ae..78db63a 100644
--- a/arch/mips/kernel/proc.c
+++ b/arch/mips/kernel/proc.c
@@ -14,6 +14,7 @@
 #include <asm/mipsregs.h>
 #include <asm/processor.h>
 #include <asm/prom.h>
+#include <asm/time.h>
 
 unsigned int vced_count, vcei_count;
 
@@ -62,6 +63,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	seq_printf(m, fmt, __cpu_name[n],
 		      (version >> 4) & 0x0f, version & 0x0f,
 		      (fp_vers >> 4) & 0x0f, fp_vers & 0x0f);
+	if (__cpu_full_name[n])
+		seq_printf(m, "model name\t\t: %s @ %uMHz\n",
+		      __cpu_full_name[n], mips_hpt_frequency / 500000);
 	seq_printf(m, "BogoMIPS\t\t: %u.%02u\n",
 		      cpu_data[n].udelay_val / (500000/HZ),
 		      (cpu_data[n].udelay_val / (5000/HZ)) % 100);
diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
index 1e8a955..9ee24ea 100644
--- a/arch/mips/loongson64/common/env.c
+++ b/arch/mips/loongson64/common/env.c
@@ -25,6 +25,7 @@
 
 u32 cpu_clock_freq;
 EXPORT_SYMBOL(cpu_clock_freq);
+static char cpu_full_name[64];
 struct efi_memory_map_loongson *loongson_memmap;
 struct loongson_system_configuration loongson_sysconf;
 
@@ -151,6 +152,8 @@ void __init prom_init_env(void)
 	loongson_sysconf.nr_nodes = (loongson_sysconf.nr_cpus +
 		loongson_sysconf.cores_per_node - 1) /
 		loongson_sysconf.cores_per_node;
+	if (!strncmp(ecpu->cpuname, "Loongson", 8))
+		strncpy(cpu_full_name, ecpu->cpuname, 64);
 
 	loongson_sysconf.pci_mem_start_addr = eirq_source->pci_mem_start_addr;
 	loongson_sysconf.pci_mem_end_addr = eirq_source->pci_mem_end_addr;
@@ -212,3 +215,18 @@ void __init prom_init_env(void)
 	}
 	pr_info("CpuClock = %u\n", cpu_clock_freq);
 }
+
+static int __init overwrite_cpu_fullname(void)
+{
+	int cpu;
+
+	if (cpu_full_name[0] == 0)
+		return 0;
+
+	for(cpu = 0; cpu < NR_CPUS; cpu++)
+		__cpu_full_name[cpu] = cpu_full_name;
+
+	return 0;
+}
+
+core_initcall(overwrite_cpu_fullname);
-- 
2.7.0

Re: [PATCH V7 8/9] MIPS: Add __cpu_full_name[] to make CPU names more human-readable

[James Hogan]

[-- Attachment #1: Type: text/plain, Size: 2329 bytes --]

On Thu, Jun 22, 2017 at 11:06:55PM +0800, Huacai Chen wrote:
> diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
> index 4eff2ae..78db63a 100644
> --- a/arch/mips/kernel/proc.c
> +++ b/arch/mips/kernel/proc.c

> @@ -62,6 +63,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
>  	seq_printf(m, fmt, __cpu_name[n],
>  		      (version >> 4) & 0x0f, version & 0x0f,
>  		      (fp_vers >> 4) & 0x0f, fp_vers & 0x0f);
> +	if (__cpu_full_name[n])
> +		seq_printf(m, "model name\t\t: %s @ %uMHz\n",
> +		      __cpu_full_name[n], mips_hpt_frequency / 500000);

If the core frequency is useful (I can imagine it being useful for
humans), maybe it should be on a separate line.

This also assumes that the mips_hpt_frequency is half the core
frequency, which may not universally be the case. Perhaps that should be
abstracted too (at some point, I suppose it doesn't matter right away).

> diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
> index 1e8a955..9ee24ea 100644
> --- a/arch/mips/loongson64/common/env.c
> +++ b/arch/mips/loongson64/common/env.c
> @@ -25,6 +25,7 @@
>  
>  u32 cpu_clock_freq;
>  EXPORT_SYMBOL(cpu_clock_freq);
> +static char cpu_full_name[64];
>  struct efi_memory_map_loongson *loongson_memmap;
>  struct loongson_system_configuration loongson_sysconf;
>  
> @@ -151,6 +152,8 @@ void __init prom_init_env(void)
>  	loongson_sysconf.nr_nodes = (loongson_sysconf.nr_cpus +
>  		loongson_sysconf.cores_per_node - 1) /
>  		loongson_sysconf.cores_per_node;
> +	if (!strncmp(ecpu->cpuname, "Loongson", 8))
> +		strncpy(cpu_full_name, ecpu->cpuname, 64);

maybe sizeof(cpu_full_name) rather than 64.

>  
>  	loongson_sysconf.pci_mem_start_addr = eirq_source->pci_mem_start_addr;
>  	loongson_sysconf.pci_mem_end_addr = eirq_source->pci_mem_end_addr;
> @@ -212,3 +215,18 @@ void __init prom_init_env(void)
>  	}
>  	pr_info("CpuClock = %u\n", cpu_clock_freq);
>  }
> +
> +static int __init overwrite_cpu_fullname(void)
> +{
> +	int cpu;
> +
> +	if (cpu_full_name[0] == 0)
> +		return 0;
> +
> +	for(cpu = 0; cpu < NR_CPUS; cpu++)

space before open bracket please

> +		__cpu_full_name[cpu] = cpu_full_name;
> +
> +	return 0;
> +}
> +
> +core_initcall(overwrite_cpu_fullname);

Cheers
James

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Re: [PATCH V7 8/9] MIPS: Add __cpu_full_name[] to make CPU names more human-readable

[James Hogan]

[-- Attachment #1: Type: text/plain, Size: 2329 bytes --]

On Thu, Jun 22, 2017 at 11:06:55PM +0800, Huacai Chen wrote:
> diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
> index 4eff2ae..78db63a 100644
> --- a/arch/mips/kernel/proc.c
> +++ b/arch/mips/kernel/proc.c

> @@ -62,6 +63,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
>  	seq_printf(m, fmt, __cpu_name[n],
>  		      (version >> 4) & 0x0f, version & 0x0f,
>  		      (fp_vers >> 4) & 0x0f, fp_vers & 0x0f);
> +	if (__cpu_full_name[n])
> +		seq_printf(m, "model name\t\t: %s @ %uMHz\n",
> +		      __cpu_full_name[n], mips_hpt_frequency / 500000);

If the core frequency is useful (I can imagine it being useful for
humans), maybe it should be on a separate line.

This also assumes that the mips_hpt_frequency is half the core
frequency, which may not universally be the case. Perhaps that should be
abstracted too (at some point, I suppose it doesn't matter right away).

> diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
> index 1e8a955..9ee24ea 100644
> --- a/arch/mips/loongson64/common/env.c
> +++ b/arch/mips/loongson64/common/env.c
> @@ -25,6 +25,7 @@
>  
>  u32 cpu_clock_freq;
>  EXPORT_SYMBOL(cpu_clock_freq);
> +static char cpu_full_name[64];
>  struct efi_memory_map_loongson *loongson_memmap;
>  struct loongson_system_configuration loongson_sysconf;
>  
> @@ -151,6 +152,8 @@ void __init prom_init_env(void)
>  	loongson_sysconf.nr_nodes = (loongson_sysconf.nr_cpus +
>  		loongson_sysconf.cores_per_node - 1) /
>  		loongson_sysconf.cores_per_node;
> +	if (!strncmp(ecpu->cpuname, "Loongson", 8))
> +		strncpy(cpu_full_name, ecpu->cpuname, 64);

maybe sizeof(cpu_full_name) rather than 64.

>  
>  	loongson_sysconf.pci_mem_start_addr = eirq_source->pci_mem_start_addr;
>  	loongson_sysconf.pci_mem_end_addr = eirq_source->pci_mem_end_addr;
> @@ -212,3 +215,18 @@ void __init prom_init_env(void)
>  	}
>  	pr_info("CpuClock = %u\n", cpu_clock_freq);
>  }
> +
> +static int __init overwrite_cpu_fullname(void)
> +{
> +	int cpu;
> +
> +	if (cpu_full_name[0] == 0)
> +		return 0;
> +
> +	for(cpu = 0; cpu < NR_CPUS; cpu++)

space before open bracket please

> +		__cpu_full_name[cpu] = cpu_full_name;
> +
> +	return 0;
> +}
> +
> +core_initcall(overwrite_cpu_fullname);

Cheers
James

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Re: [PATCH V7 8/9] MIPS: Add __cpu_full_name[] to make CPU names more human-readable

[Ralf Baechle]

On Fri, Jun 23, 2017 at 04:15:07PM +0100, James Hogan wrote:

> On Thu, Jun 22, 2017 at 11:06:55PM +0800, Huacai Chen wrote:
> > diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
> > index 4eff2ae..78db63a 100644
> > --- a/arch/mips/kernel/proc.c
> > +++ b/arch/mips/kernel/proc.c
> 
> > @@ -62,6 +63,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
> >  	seq_printf(m, fmt, __cpu_name[n],
> >  		      (version >> 4) & 0x0f, version & 0x0f,
> >  		      (fp_vers >> 4) & 0x0f, fp_vers & 0x0f);
> > +	if (__cpu_full_name[n])
> > +		seq_printf(m, "model name\t\t: %s @ %uMHz\n",
> > +		      __cpu_full_name[n], mips_hpt_frequency / 500000);
> 
> If the core frequency is useful (I can imagine it being useful for
> humans), maybe it should be on a separate line.
> 
> This also assumes that the mips_hpt_frequency is half the core
> frequency, which may not universally be the case. Perhaps that should be
> abstracted too (at some point, I suppose it doesn't matter right away).

Indeed, there is a number of cores where the counter is incrementing at
the full clock rate and some - I think this was the IDT 5230/5260 class
of devices where the clock rate can be configured through a cold reset
time bitstream but the rate in use can not be detected by software in
a configuration register, so it has to be meassured by comparing to
another known clock.  Whops..

Making the clock part of the name is probably sensible on x86 where there
seem to be different CPU packages being marketed for different clock
rates, so this is more of a marketing name in contrast to an actual
core type.

It's not like on MIPS we're not suffering from creative CPU naming as
well.  It all started in '91 with when the R4000 with its 8k primary
caches was upgraded and then primarily due to its 16k caches sold as
the R4400.  From a software perspective there isn't much of a difference
so calling the R4400 an R4000 is sensible but users might miss an inch
or two if their R4400 is called a lowly R4000 ;-)

  Ralf

Re: [PATCH V7 8/9] MIPS: Add __cpu_full_name[] to make CPU names more human-readable

[Huacai Chen]

OK, I'll rework this patch.

Huacai

On Sat, Jun 24, 2017 at 1:11 AM, Ralf Baechle <ralf@linux-mips.org> wrote:
> On Fri, Jun 23, 2017 at 04:15:07PM +0100, James Hogan wrote:
>
>> On Thu, Jun 22, 2017 at 11:06:55PM +0800, Huacai Chen wrote:
>> > diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
>> > index 4eff2ae..78db63a 100644
>> > --- a/arch/mips/kernel/proc.c
>> > +++ b/arch/mips/kernel/proc.c
>>
>> > @@ -62,6 +63,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
>> >     seq_printf(m, fmt, __cpu_name[n],
>> >                   (version >> 4) & 0x0f, version & 0x0f,
>> >                   (fp_vers >> 4) & 0x0f, fp_vers & 0x0f);
>> > +   if (__cpu_full_name[n])
>> > +           seq_printf(m, "model name\t\t: %s @ %uMHz\n",
>> > +                 __cpu_full_name[n], mips_hpt_frequency / 500000);
>>
>> If the core frequency is useful (I can imagine it being useful for
>> humans), maybe it should be on a separate line.
>>
>> This also assumes that the mips_hpt_frequency is half the core
>> frequency, which may not universally be the case. Perhaps that should be
>> abstracted too (at some point, I suppose it doesn't matter right away).
>
> Indeed, there is a number of cores where the counter is incrementing at
> the full clock rate and some - I think this was the IDT 5230/5260 class
> of devices where the clock rate can be configured through a cold reset
> time bitstream but the rate in use can not be detected by software in
> a configuration register, so it has to be meassured by comparing to
> another known clock.  Whops..
>
> Making the clock part of the name is probably sensible on x86 where there
> seem to be different CPU packages being marketed for different clock
> rates, so this is more of a marketing name in contrast to an actual
> core type.
>
> It's not like on MIPS we're not suffering from creative CPU naming as
> well.  It all started in '91 with when the R4000 with its 8k primary
> caches was upgraded and then primarily due to its 16k caches sold as
> the R4400.  From a software perspective there isn't much of a difference
> so calling the R4400 an R4000 is sensible but users might miss an inch
> or two if their R4400 is called a lowly R4000 ;-)
>
>   Ralf
>

[PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[Huacai Chen]

On the Loongson-2G/2H/3A/3B there is a hardware flaw that ll/sc and
lld/scd is very weak ordering. We should add sync instructions before
each ll/lld and after the last sc/scd to workaround. Otherwise, this
flaw will cause deadlock occationally (e.g. when doing heavy load test
with LTP).

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/atomic.h                 | 107 ++++++++++
 arch/mips/include/asm/bitops.h                 | 273 +++++++++++++++++++------
 arch/mips/include/asm/cmpxchg.h                |  54 +++++
 arch/mips/include/asm/edac.h                   |  33 ++-
 arch/mips/include/asm/futex.h                  |  62 ++++++
 arch/mips/include/asm/local.h                  |  34 +++
 arch/mips/include/asm/mach-cavium-octeon/war.h |   1 +
 arch/mips/include/asm/mach-generic/war.h       |   1 +
 arch/mips/include/asm/mach-ip22/war.h          |   1 +
 arch/mips/include/asm/mach-ip27/war.h          |   1 +
 arch/mips/include/asm/mach-ip28/war.h          |   1 +
 arch/mips/include/asm/mach-ip32/war.h          |   1 +
 arch/mips/include/asm/mach-loongson64/war.h    |  26 +++
 arch/mips/include/asm/mach-malta/war.h         |   1 +
 arch/mips/include/asm/mach-pmcs-msp71xx/war.h  |   1 +
 arch/mips/include/asm/mach-rc32434/war.h       |   1 +
 arch/mips/include/asm/mach-rm/war.h            |   1 +
 arch/mips/include/asm/mach-sibyte/war.h        |   1 +
 arch/mips/include/asm/mach-tx49xx/war.h        |   1 +
 arch/mips/include/asm/pgtable.h                |  19 ++
 arch/mips/include/asm/spinlock.h               | 142 +++++++++++++
 arch/mips/include/asm/war.h                    |   8 +
 arch/mips/kernel/syscall.c                     |  34 +++
 arch/mips/loongson64/Platform                  |   3 +
 arch/mips/mm/tlbex.c                           |  17 ++
 25 files changed, 757 insertions(+), 67 deletions(-)
 create mode 100644 arch/mips/include/asm/mach-loongson64/war.h

diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 0ab176b..e0002c58 100644
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i, atomic_t * v)			      \
 		"	.set	mips0					\n"   \
 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
 		: "Ir" (i));						      \
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
+		int temp;						      \
+									      \
+		do {							      \
+			__asm__ __volatile__(				      \
+			"	.set	"MIPS_ISA_LEVEL"		\n"   \
+			__WEAK_LLSC_MB					      \
+			"	ll	%0, %1		# atomic_" #op "\n"   \
+			"	" #asm_op " %0, %2			\n"   \
+			"	sc	%0, %1				\n"   \
+			"	.set	mips0				\n"   \
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
+			: "Ir" (i));					      \
+		} while (unlikely(!temp));				      \
+									      \
+		smp_llsc_mb();						      \
 	} else if (kernel_uses_llsc) {					      \
 		int temp;						      \
 									      \
@@ -97,6 +113,23 @@ static __inline__ int atomic_##op##_return_relaxed(int i, atomic_t * v)	      \
 		: "=&r" (result), "=&r" (temp),				      \
 		  "+" GCC_OFF_SMALL_ASM() (v->counter)			      \
 		: "Ir" (i));						      \
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
+		int temp;						      \
+									      \
+		do {							      \
+			__asm__ __volatile__(				      \
+			"	.set	"MIPS_ISA_LEVEL"		\n"   \
+			__WEAK_LLSC_MB					      \
+			"	ll	%1, %2	# atomic_" #op "_return	\n"   \
+			"	" #asm_op " %0, %1, %3			\n"   \
+			"	sc	%0, %2				\n"   \
+			"	.set	mips0				\n"   \
+			: "=&r" (result), "=&r" (temp),			      \
+			  "+" GCC_OFF_SMALL_ASM() (v->counter)		      \
+			: "Ir" (i));					      \
+		} while (unlikely(!result));				      \
+									      \
+		result = temp; result c_op i;				      \
 	} else if (kernel_uses_llsc) {					      \
 		int temp;						      \
 									      \
@@ -237,6 +270,26 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
 		  "+" GCC_OFF_SMALL_ASM() (v->counter)
 		: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		int temp;
+
+		__asm__ __volatile__(
+		"	.set	"MIPS_ISA_LEVEL"			\n"
+		"1:				# atomic_sub_if_positive\n"
+		__WEAK_LLSC_MB
+		"	ll	%1, %2					\n"
+		"	subu	%0, %1, %3				\n"
+		"	bltz	%0, 1f					\n"
+		"	sc	%0, %2					\n"
+		"	.set	noreorder				\n"
+		"	beqz	%0, 1b					\n"
+		"	 subu	%0, %1, %3				\n"
+		"	.set	reorder					\n"
+		"1:							\n"
+		"	.set	mips0					\n"
+		: "=&r" (result), "=&r" (temp),
+		  "+" GCC_OFF_SMALL_ASM() (v->counter)
+		: "Ir" (i));
 	} else if (kernel_uses_llsc) {
 		int temp;
 
@@ -398,6 +451,22 @@ static __inline__ void atomic64_##op(long i, atomic64_t * v)		      \
 		"	.set	mips0					\n"   \
 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
 		: "Ir" (i));						      \
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
+		long temp;						      \
+									      \
+		do {							      \
+			__asm__ __volatile__(				      \
+			"	.set	"MIPS_ISA_LEVEL"		\n"   \
+			__WEAK_LLSC_MB					      \
+			"	lld	%0, %1		# atomic64_" #op "\n" \
+			"	" #asm_op " %0, %2			\n"   \
+			"	scd	%0, %1				\n"   \
+			"	.set	mips0				\n"   \
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
+			: "Ir" (i));					      \
+		} while (unlikely(!temp));				      \
+									      \
+		smp_llsc_mb();						      \
 	} else if (kernel_uses_llsc) {					      \
 		long temp;						      \
 									      \
@@ -439,6 +508,24 @@ static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
 		: "=&r" (result), "=&r" (temp),				      \
 		  "+" GCC_OFF_SMALL_ASM() (v->counter)			      \
 		: "Ir" (i));						      \
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
+		long temp;						      \
+									      \
+		do {							      \
+			__asm__ __volatile__(				      \
+			"	.set	"MIPS_ISA_LEVEL"		\n"   \
+			__WEAK_LLSC_MB					      \
+			"	lld	%1, %2	# atomic64_" #op "_return\n"  \
+			"	" #asm_op " %0, %1, %3			\n"   \
+			"	scd	%0, %2				\n"   \
+			"	.set	mips0				\n"   \
+			: "=&r" (result), "=&r" (temp),			      \
+			  "=" GCC_OFF_SMALL_ASM() (v->counter)		      \
+			: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)	      \
+			: "memory");					      \
+		} while (unlikely(!result));				      \
+									      \
+		result = temp; result c_op i;				      \
 	} else if (kernel_uses_llsc) {					      \
 		long temp;						      \
 									      \
@@ -582,6 +669,26 @@ static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
 		  "=" GCC_OFF_SMALL_ASM() (v->counter)
 		: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		long temp;
+
+		__asm__ __volatile__(
+		"	.set	"MIPS_ISA_LEVEL"			\n"
+		"1:				# atomic64_sub_if_positive\n"
+		__WEAK_LLSC_MB
+		"	lld	%1, %2					\n"
+		"	dsubu	%0, %1, %3				\n"
+		"	bltz	%0, 1f					\n"
+		"	scd	%0, %2					\n"
+		"	.set	noreorder				\n"
+		"	beqz	%0, 1b					\n"
+		"	 dsubu	%0, %1, %3				\n"
+		"	.set	reorder					\n"
+		"1:							\n"
+		"	.set	mips0					\n"
+		: "=&r" (result), "=&r" (temp),
+		  "+" GCC_OFF_SMALL_ASM() (v->counter)
+		: "Ir" (i));
 	} else if (kernel_uses_llsc) {
 		long temp;
 
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index fa57cef..6bef54a 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -68,26 +68,54 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
 		: "ir" (1UL << bit), GCC_OFF_SMALL_ASM() (*m));
 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
-		do {
-			__asm__ __volatile__(
-			"	" __LL "%0, %1		# set_bit	\n"
-			"	" __INS "%0, %3, %2, 1			\n"
-			"	" __SC "%0, %1				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
-			: "ir" (bit), "r" (~0));
-		} while (unlikely(!temp));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				__WEAK_LLSC_MB
+				"	" __LL "%0, %1		# set_bit	\n"
+				"	" __INS "%0, %3, %2, 1			\n"
+				"	" __SC "%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (bit), "r" (~0));
+			} while (unlikely(!temp));
+			smp_llsc_mb();
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	" __LL "%0, %1		# set_bit	\n"
+				"	" __INS "%0, %3, %2, 1			\n"
+				"	" __SC "%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (bit), "r" (~0));
+			} while (unlikely(!temp));
+		}
 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
 	} else if (kernel_uses_llsc) {
-		do {
-			__asm__ __volatile__(
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	" __LL "%0, %1		# set_bit	\n"
-			"	or	%0, %2				\n"
-			"	" __SC	"%0, %1				\n"
-			"	.set	mips0				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
-			: "ir" (1UL << bit));
-		} while (unlikely(!temp));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				__WEAK_LLSC_MB
+				"	" __LL "%0, %1		# set_bit	\n"
+				"	or	%0, %2				\n"
+				"	" __SC	"%0, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (1UL << bit));
+			} while (unlikely(!temp));
+			smp_llsc_mb();
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				"	" __LL "%0, %1		# set_bit	\n"
+				"	or	%0, %2				\n"
+				"	" __SC	"%0, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (1UL << bit));
+			} while (unlikely(!temp));
+		}
 	} else
 		__mips_set_bit(nr, addr);
 }
@@ -120,26 +148,54 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
 		: "ir" (~(1UL << bit)));
 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
 	} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
-		do {
-			__asm__ __volatile__(
-			"	" __LL "%0, %1		# clear_bit	\n"
-			"	" __INS "%0, $0, %2, 1			\n"
-			"	" __SC "%0, %1				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
-			: "ir" (bit));
-		} while (unlikely(!temp));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				__WEAK_LLSC_MB
+				"	" __LL "%0, %1		# clear_bit	\n"
+				"	" __INS "%0, $0, %2, 1			\n"
+				"	" __SC "%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (bit));
+			} while (unlikely(!temp));
+			smp_llsc_mb();
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	" __LL "%0, %1		# clear_bit	\n"
+				"	" __INS "%0, $0, %2, 1			\n"
+				"	" __SC "%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (bit));
+			} while (unlikely(!temp));
+		}
 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
 	} else if (kernel_uses_llsc) {
-		do {
-			__asm__ __volatile__(
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	" __LL "%0, %1		# clear_bit	\n"
-			"	and	%0, %2				\n"
-			"	" __SC "%0, %1				\n"
-			"	.set	mips0				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
-			: "ir" (~(1UL << bit)));
-		} while (unlikely(!temp));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				__WEAK_LLSC_MB
+				"	" __LL "%0, %1		# clear_bit	\n"
+				"	and	%0, %2				\n"
+				"	" __SC "%0, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (~(1UL << bit)));
+			} while (unlikely(!temp));
+			smp_llsc_mb();
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				"	" __LL "%0, %1		# clear_bit	\n"
+				"	and	%0, %2				\n"
+				"	" __SC "%0, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+				: "ir" (~(1UL << bit)));
+			} while (unlikely(!temp));
+		}
 	} else
 		__mips_clear_bit(nr, addr);
 }
@@ -184,6 +240,23 @@ static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
 		"	.set	mips0				\n"
 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
 		: "ir" (1UL << bit));
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	" __LL "%0, %1		# change_bit	\n"
+			"	xor	%0, %2				\n"
+			"	" __SC	"%0, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (1UL << bit));
+		} while (unlikely(!temp));
+
+		smp_llsc_mb();
 	} else if (kernel_uses_llsc) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
@@ -233,6 +306,24 @@ static inline int test_and_set_bit(unsigned long nr,
 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
 		: "r" (1UL << bit)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	" __LL "%0, %1	# test_and_set_bit	\n"
+			"	or	%2, %0, %3			\n"
+			"	" __SC	"%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
 	} else if (kernel_uses_llsc) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
@@ -287,6 +378,24 @@ static inline int test_and_set_bit_lock(unsigned long nr,
 		: "=&r" (temp), "+m" (*m), "=&r" (res)
 		: "r" (1UL << bit)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	" __LL "%0, %1	# test_and_set_bit	\n"
+			"	or	%2, %0, %3			\n"
+			"	" __SC	"%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
 	} else if (kernel_uses_llsc) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
@@ -348,33 +457,63 @@ static inline int test_and_clear_bit(unsigned long nr,
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
 
-		do {
-			__asm__ __volatile__(
-			"	" __LL	"%0, %1 # test_and_clear_bit	\n"
-			"	" __EXT "%2, %0, %3, 1			\n"
-			"	" __INS "%0, $0, %3, 1			\n"
-			"	" __SC	"%0, %1				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
-			: "ir" (bit)
-			: "memory");
-		} while (unlikely(!temp));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				__WEAK_LLSC_MB
+				"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+				"	" __EXT "%2, %0, %3, 1			\n"
+				"	" __INS "%0, $0, %3, 1			\n"
+				"	" __SC	"%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+				: "ir" (bit)
+				: "memory");
+			} while (unlikely(!temp));
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+				"	" __EXT "%2, %0, %3, 1			\n"
+				"	" __INS "%0, $0, %3, 1			\n"
+				"	" __SC	"%0, %1				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+				: "ir" (bit)
+				: "memory");
+			} while (unlikely(!temp));
+		}
 #endif
 	} else if (kernel_uses_llsc) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
 
-		do {
-			__asm__ __volatile__(
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	" __LL	"%0, %1 # test_and_clear_bit	\n"
-			"	or	%2, %0, %3			\n"
-			"	xor	%2, %3				\n"
-			"	" __SC	"%2, %1				\n"
-			"	.set	mips0				\n"
-			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
-			: "r" (1UL << bit)
-			: "memory");
-		} while (unlikely(!res));
+		if (LOONGSON_LLSC_WAR) {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				__WEAK_LLSC_MB
+				"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+				"	or	%2, %0, %3			\n"
+				"	xor	%2, %3				\n"
+				"	" __SC	"%2, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+				: "r" (1UL << bit)
+				: "memory");
+			} while (unlikely(!res));
+		} else {
+			do {
+				__asm__ __volatile__(
+				"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+				"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+				"	or	%2, %0, %3			\n"
+				"	xor	%2, %3				\n"
+				"	" __SC	"%2, %1				\n"
+				"	.set	mips0				\n"
+				: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+				: "r" (1UL << bit)
+				: "memory");
+			} while (unlikely(!res));
+		}
 
 		res = temp & (1UL << bit);
 	} else
@@ -416,6 +555,24 @@ static inline int test_and_change_bit(unsigned long nr,
 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
 		: "r" (1UL << bit)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	" __LL	"%0, %1 # test_and_change_bit	\n"
+			"	xor	%2, %0, %3			\n"
+			"	" __SC	"\t%2, %1			\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
 	} else if (kernel_uses_llsc) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
 		unsigned long temp;
diff --git a/arch/mips/include/asm/cmpxchg.h b/arch/mips/include/asm/cmpxchg.h
index b71ab4a..5bfd70d 100644
--- a/arch/mips/include/asm/cmpxchg.h
+++ b/arch/mips/include/asm/cmpxchg.h
@@ -34,6 +34,24 @@ static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
 		: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m), "=&r" (dummy)
 		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long dummy;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	ll	%0, %3		# xchg_u32	\n"
+			"	.set	mips0				\n"
+			"	move	%2, %z4				\n"
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	sc	%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m),
+			  "=&r" (dummy)
+			: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
+			: "memory");
+		} while (unlikely(!dummy));
 	} else if (kernel_uses_llsc) {
 		unsigned long dummy;
 
@@ -85,6 +103,22 @@ static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val)
 		: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m), "=&r" (dummy)
 		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long dummy;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			__WEAK_LLSC_MB
+			"	lld	%0, %3		# xchg_u64	\n"
+			"	move	%2, %z4				\n"
+			"	scd	%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m),
+			  "=&r" (dummy)
+			: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
+			: "memory");
+		} while (unlikely(!dummy));
 	} else if (kernel_uses_llsc) {
 		unsigned long dummy;
 
@@ -159,6 +193,26 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz
 		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
 		: GCC_OFF_SMALL_ASM() (*m), "Jr" (old), "Jr" (new)		\
 		: "memory");						\
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		\
+		__asm__ __volatile__(					\
+		"	.set	push				\n"	\
+		"	.set	noat				\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
+		"1:				# __cmpxchg_asm \n"	\
+		__WEAK_LLSC_MB						\
+		"	" ld "	%0, %2				\n"	\
+		"	bne	%0, %z3, 2f			\n"	\
+		"	.set	mips0				\n"	\
+		"	move	$1, %z4				\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
+		"	" st "	$1, %1				\n"	\
+		"	beqz	$1, 1b				\n"	\
+		"	.set	pop				\n"	\
+		"2:						\n"	\
+		__WEAK_LLSC_MB						\
+		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
+		: GCC_OFF_SMALL_ASM() (*m), "Jr" (old), "Jr" (new)		\
+		: "memory");						\
 	} else if (kernel_uses_llsc) {					\
 		__asm__ __volatile__(					\
 		"	.set	push				\n"	\
diff --git a/arch/mips/include/asm/edac.h b/arch/mips/include/asm/edac.h
index 980b165..a864aa9 100644
--- a/arch/mips/include/asm/edac.h
+++ b/arch/mips/include/asm/edac.h
@@ -19,15 +19,30 @@ static inline void edac_atomic_scrub(void *va, u32 size)
 		 * Intel: asm("lock; addl $0, %0"::"m"(*virt_addr));
 		 */
 
-		__asm__ __volatile__ (
-		"	.set	mips2					\n"
-		"1:	ll	%0, %1		# edac_atomic_scrub	\n"
-		"	addu	%0, $0					\n"
-		"	sc	%0, %1					\n"
-		"	beqz	%0, 1b					\n"
-		"	.set	mips0					\n"
-		: "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*virt_addr)
-		: GCC_OFF_SMALL_ASM() (*virt_addr));
+		if (LOONGSON_LLSC_WAR) {
+			__asm__ __volatile__ (
+			"	.set	mips2					\n"
+			"1:				# edac_atomic_scrub	\n"
+			__WEAK_LLSC_MB
+			"	ll	%0, %1					\n"
+			"	addu	%0, $0					\n"
+			"	sc	%0, %1					\n"
+			"	beqz	%0, 1b					\n"
+			"	.set	mips0					\n"
+			: "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*virt_addr)
+			: GCC_OFF_SMALL_ASM() (*virt_addr));
+			smp_llsc_mb();
+		} else {
+			__asm__ __volatile__ (
+			"	.set	mips2					\n"
+			"1:	ll	%0, %1		# edac_atomic_scrub	\n"
+			"	addu	%0, $0					\n"
+			"	sc	%0, %1					\n"
+			"	beqz	%0, 1b					\n"
+			"	.set	mips0					\n"
+			: "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*virt_addr)
+			: GCC_OFF_SMALL_ASM() (*virt_addr));
+		}
 
 		virt_addr++;
 	}
diff --git a/arch/mips/include/asm/futex.h b/arch/mips/include/asm/futex.h
index 1de190b..3e2741f 100644
--- a/arch/mips/include/asm/futex.h
+++ b/arch/mips/include/asm/futex.h
@@ -49,6 +49,37 @@
 		: "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg),	\
 		  "i" (-EFAULT)						\
 		: "memory");						\
+	} else if (cpu_has_llsc && LOONGSON_LLSC_WAR) {					\
+		__asm__ __volatile__(					\
+		"	.set	push				\n"	\
+		"	.set	noat				\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
+		"1:				 # __futex_atomic_op\n"	\
+		__WEAK_LLSC_MB						\
+		"	"user_ll("%1", "%4")"			\n"	\
+		"	.set	mips0				\n"	\
+		"	" insn	"				\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
+		"2:	"user_sc("$1", "%2")"			\n"	\
+		"	beqz	$1, 1b				\n"	\
+		__WEAK_LLSC_MB						\
+		"3:						\n"	\
+		"	.insn					\n"	\
+		"	.set	pop				\n"	\
+		"	.set	mips0				\n"	\
+		"	.section .fixup,\"ax\"			\n"	\
+		"4:	li	%0, %6				\n"	\
+		"	j	3b				\n"	\
+		"	.previous				\n"	\
+		"	.section __ex_table,\"a\"		\n"	\
+		"	"__UA_ADDR "\t(1b + 4), 4b		\n"	\
+		"	"__UA_ADDR "\t(2b + 0), 4b		\n"	\
+		"	.previous				\n"	\
+		: "=r" (ret), "=&r" (oldval),				\
+		  "=" GCC_OFF_SMALL_ASM() (*uaddr)				\
+		: "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg),	\
+		  "i" (-EFAULT)						\
+		: "memory");						\
 	} else if (cpu_has_llsc) {					\
 		__asm__ __volatile__(					\
 		"	.set	push				\n"	\
@@ -178,6 +209,37 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 		: GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
 		  "i" (-EFAULT)
 		: "memory");
+	} else if (cpu_has_llsc && LOONGSON_LLSC_WAR) {
+		__asm__ __volatile__(
+		"# futex_atomic_cmpxchg_inatomic			\n"
+		"	.set	push					\n"
+		"	.set	noat					\n"
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
+		"1:							\n"
+		__WEAK_LLSC_MB
+		"	"user_ll("%1", "%3")"				\n"
+		"	bne	%1, %z4, 3f				\n"
+		"	.set	mips0					\n"
+		"	move	$1, %z5					\n"
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
+		"2:	"user_sc("$1", "%2")"				\n"
+		"	beqz	$1, 1b					\n"
+		__WEAK_LLSC_MB
+		"3:							\n"
+		"	.insn						\n"
+		"	.set	pop					\n"
+		"	.section .fixup,\"ax\"				\n"
+		"4:	li	%0, %6					\n"
+		"	j	3b					\n"
+		"	.previous					\n"
+		"	.section __ex_table,\"a\"			\n"
+		"	"__UA_ADDR "\t(1b + 4), 4b			\n"
+		"	"__UA_ADDR "\t(2b + 0), 4b			\n"
+		"	.previous					\n"
+		: "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr)
+		: GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
+		  "i" (-EFAULT)
+		: "memory");
 	} else if (cpu_has_llsc) {
 		__asm__ __volatile__(
 		"# futex_atomic_cmpxchg_inatomic			\n"
diff --git a/arch/mips/include/asm/local.h b/arch/mips/include/asm/local.h
index 8feaed6..a6e9d06 100644
--- a/arch/mips/include/asm/local.h
+++ b/arch/mips/include/asm/local.h
@@ -44,6 +44,23 @@ static __inline__ long local_add_return(long i, local_t * l)
 		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
 		: "Ir" (i), "m" (l->a.counter)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
+		"1:							\n"
+			__WEAK_LLSC_MB
+			__LL	"%1, %2		# local_add_return	\n"
+		"	addu	%0, %1, %3				\n"
+			__SC	"%0, %2					\n"
+		"	beqz	%0, 1b					\n"
+		"	addu	%0, %1, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+		: "Ir" (i), "m" (l->a.counter)
+		: "memory");
+		smp_llsc_mb();
 	} else if (kernel_uses_llsc) {
 		unsigned long temp;
 
@@ -89,6 +106,23 @@ static __inline__ long local_sub_return(long i, local_t * l)
 		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
 		: "Ir" (i), "m" (l->a.counter)
 		: "memory");
+	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
+		"1:							\n"
+			__WEAK_LLSC_MB
+			__LL	"%1, %2		# local_sub_return	\n"
+		"	subu	%0, %1, %3				\n"
+			__SC	"%0, %2					\n"
+		"	beqz	%0, 1b					\n"
+		"	subu	%0, %1, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+		: "Ir" (i), "m" (l->a.counter)
+		: "memory");
+		smp_llsc_mb();
 	} else if (kernel_uses_llsc) {
 		unsigned long temp;
 
diff --git a/arch/mips/include/asm/mach-cavium-octeon/war.h b/arch/mips/include/asm/mach-cavium-octeon/war.h
index 35c80be..1c43fb2 100644
--- a/arch/mips/include/asm/mach-cavium-octeon/war.h
+++ b/arch/mips/include/asm/mach-cavium-octeon/war.h
@@ -20,6 +20,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #define CAVIUM_OCTEON_DCACHE_PREFETCH_WAR	\
diff --git a/arch/mips/include/asm/mach-generic/war.h b/arch/mips/include/asm/mach-generic/war.h
index a1bc2e7..2dd9bf5 100644
--- a/arch/mips/include/asm/mach-generic/war.h
+++ b/arch/mips/include/asm/mach-generic/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MACH_GENERIC_WAR_H */
diff --git a/arch/mips/include/asm/mach-ip22/war.h b/arch/mips/include/asm/mach-ip22/war.h
index fba6405..66ddafa 100644
--- a/arch/mips/include/asm/mach-ip22/war.h
+++ b/arch/mips/include/asm/mach-ip22/war.h
@@ -23,6 +23,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_IP22_WAR_H */
diff --git a/arch/mips/include/asm/mach-ip27/war.h b/arch/mips/include/asm/mach-ip27/war.h
index 4ee0e4b..63ee1e5 100644
--- a/arch/mips/include/asm/mach-ip27/war.h
+++ b/arch/mips/include/asm/mach-ip27/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			1
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_IP27_WAR_H */
diff --git a/arch/mips/include/asm/mach-ip28/war.h b/arch/mips/include/asm/mach-ip28/war.h
index 4821c7b..e455320 100644
--- a/arch/mips/include/asm/mach-ip28/war.h
+++ b/arch/mips/include/asm/mach-ip28/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			1
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_IP28_WAR_H */
diff --git a/arch/mips/include/asm/mach-ip32/war.h b/arch/mips/include/asm/mach-ip32/war.h
index 9807ecd..2bd4caf 100644
--- a/arch/mips/include/asm/mach-ip32/war.h
+++ b/arch/mips/include/asm/mach-ip32/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	1
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_IP32_WAR_H */
diff --git a/arch/mips/include/asm/mach-loongson64/war.h b/arch/mips/include/asm/mach-loongson64/war.h
new file mode 100644
index 0000000..c5f9aaa
--- /dev/null
+++ b/arch/mips/include/asm/mach-loongson64/war.h
@@ -0,0 +1,26 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2002, 2004, 2007 by Ralf Baechle <ralf@linux-mips.org>
+ * Copyright (C) 2015, 2016 by Huacai Chen <chenhc@lemote.com>
+ */
+#ifndef __ASM_MIPS_MACH_LOONGSON64_WAR_H
+#define __ASM_MIPS_MACH_LOONGSON64_WAR_H
+
+#define R4600_V1_INDEX_ICACHEOP_WAR	0
+#define R4600_V1_HIT_CACHEOP_WAR	0
+#define R4600_V2_HIT_CACHEOP_WAR	0
+#define R5432_CP0_INTERRUPT_WAR		0
+#define BCM1250_M3_WAR			0
+#define SIBYTE_1956_WAR			0
+#define MIPS4K_ICACHE_REFILL_WAR	0
+#define MIPS_CACHE_SYNC_WAR		0
+#define TX49XX_ICACHE_INDEX_INV_WAR	0
+#define ICACHE_REFILLS_WORKAROUND_WAR	0
+#define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		IS_ENABLED(CONFIG_CPU_LOONGSON3)
+#define MIPS34K_MISSED_ITLB_WAR		0
+
+#endif /* __ASM_MIPS_MACH_LOONGSON64_WAR_H */
diff --git a/arch/mips/include/asm/mach-malta/war.h b/arch/mips/include/asm/mach-malta/war.h
index d068fc4..c380825 100644
--- a/arch/mips/include/asm/mach-malta/war.h
+++ b/arch/mips/include/asm/mach-malta/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	1
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_MIPS_WAR_H */
diff --git a/arch/mips/include/asm/mach-pmcs-msp71xx/war.h b/arch/mips/include/asm/mach-pmcs-msp71xx/war.h
index a60bf9d..8c5f396 100644
--- a/arch/mips/include/asm/mach-pmcs-msp71xx/war.h
+++ b/arch/mips/include/asm/mach-pmcs-msp71xx/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #if defined(CONFIG_PMC_MSP7120_EVAL) || defined(CONFIG_PMC_MSP7120_GW) || \
 	defined(CONFIG_PMC_MSP7120_FPGA)
 #define MIPS34K_MISSED_ITLB_WAR		1
diff --git a/arch/mips/include/asm/mach-rc32434/war.h b/arch/mips/include/asm/mach-rc32434/war.h
index 1bfd489a..72d2926 100644
--- a/arch/mips/include/asm/mach-rc32434/war.h
+++ b/arch/mips/include/asm/mach-rc32434/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_MIPS_WAR_H */
diff --git a/arch/mips/include/asm/mach-rm/war.h b/arch/mips/include/asm/mach-rm/war.h
index a3dde98..5683389 100644
--- a/arch/mips/include/asm/mach-rm/war.h
+++ b/arch/mips/include/asm/mach-rm/war.h
@@ -23,6 +23,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_RM_WAR_H */
diff --git a/arch/mips/include/asm/mach-sibyte/war.h b/arch/mips/include/asm/mach-sibyte/war.h
index 520f8fc..b9d7bcb 100644
--- a/arch/mips/include/asm/mach-sibyte/war.h
+++ b/arch/mips/include/asm/mach-sibyte/war.h
@@ -34,6 +34,7 @@ extern int sb1250_m3_workaround_needed(void);
 #define TX49XX_ICACHE_INDEX_INV_WAR	0
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_SIBYTE_WAR_H */
diff --git a/arch/mips/include/asm/mach-tx49xx/war.h b/arch/mips/include/asm/mach-tx49xx/war.h
index a8e2c58..fd44710 100644
--- a/arch/mips/include/asm/mach-tx49xx/war.h
+++ b/arch/mips/include/asm/mach-tx49xx/war.h
@@ -19,6 +19,7 @@
 #define TX49XX_ICACHE_INDEX_INV_WAR	1
 #define ICACHE_REFILLS_WORKAROUND_WAR	0
 #define R10000_LLSC_WAR			0
+#define LOONGSON_LLSC_WAR		0
 #define MIPS34K_MISSED_ITLB_WAR		0
 
 #endif /* __ASM_MIPS_MACH_TX49XX_WAR_H */
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 9e9e944..d534185 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -228,6 +228,25 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
 			"	.set	mips0				\n"
 			: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
 			: [global] "r" (page_global));
+		} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
+			__asm__ __volatile__ (
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	.set	push				\n"
+			"	.set	noreorder			\n"
+			"1:						\n"
+				__WEAK_LLSC_MB
+				__LL	"%[tmp], %[buddy]		\n"
+			"	bnez	%[tmp], 2f			\n"
+			"	 or	%[tmp], %[tmp], %[global]	\n"
+				__SC	"%[tmp], %[buddy]		\n"
+			"	beqz	%[tmp], 1b			\n"
+			"	nop					\n"
+			"2:						\n"
+			"	.set	pop				\n"
+			"	.set	mips0				\n"
+			: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
+			: [global] "r" (page_global));
+			smp_llsc_mb();
 		} else if (kernel_uses_llsc) {
 			__asm__ __volatile__ (
 			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h
index a8df44d..1e44b76 100644
--- a/arch/mips/include/asm/spinlock.h
+++ b/arch/mips/include/asm/spinlock.h
@@ -114,6 +114,41 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
 		  [ticket] "=&r" (tmp),
 		  [my_ticket] "=&r" (my_ticket)
 		: [inc] "r" (inc));
+	} else if (LOONGSON_LLSC_WAR) {
+		__asm__ __volatile__ (
+		"	.set push		# arch_spin_lock	\n"
+		"	.set noreorder					\n"
+		"							\n"
+		"1:							\n"
+		__WEAK_LLSC_MB
+		"	ll	%[ticket], %[ticket_ptr]		\n"
+		"	addu	%[my_ticket], %[ticket], %[inc]		\n"
+		"	sc	%[my_ticket], %[ticket_ptr]		\n"
+		"	beqz	%[my_ticket], 1b			\n"
+		"	 srl	%[my_ticket], %[ticket], 16		\n"
+		"	andi	%[ticket], %[ticket], 0xffff		\n"
+		"	bne	%[ticket], %[my_ticket], 4f		\n"
+		"	 subu	%[ticket], %[my_ticket], %[ticket]	\n"
+		"2:							\n"
+		"	.subsection 2					\n"
+		"4:	andi	%[ticket], %[ticket], 0xffff		\n"
+		"	sll	%[ticket], 5				\n"
+		"							\n"
+		"6:	bnez	%[ticket], 6b				\n"
+		"	 subu	%[ticket], 1				\n"
+		"							\n"
+		"	lhu	%[ticket], %[serving_now_ptr]		\n"
+		"	beq	%[ticket], %[my_ticket], 2b		\n"
+		"	 subu	%[ticket], %[my_ticket], %[ticket]	\n"
+		"	b	4b					\n"
+		"	 subu	%[ticket], %[ticket], 1			\n"
+		"	.previous					\n"
+		"	.set pop					\n"
+		: [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
+		  [serving_now_ptr] "+m" (lock->h.serving_now),
+		  [ticket] "=&r" (tmp),
+		  [my_ticket] "=&r" (my_ticket)
+		: [inc] "r" (inc));
 	} else {
 		__asm__ __volatile__ (
 		"	.set push		# arch_spin_lock	\n"
@@ -189,6 +224,32 @@ static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock)
 		  [my_ticket] "=&r" (tmp2),
 		  [now_serving] "=&r" (tmp3)
 		: [inc] "r" (inc));
+	} if (LOONGSON_LLSC_WAR) {
+		__asm__ __volatile__ (
+		"	.set push		# arch_spin_trylock	\n"
+		"	.set noreorder					\n"
+		"							\n"
+		"1:							\n"
+		__WEAK_LLSC_MB
+		"	ll	%[ticket], %[ticket_ptr]		\n"
+		"	srl	%[my_ticket], %[ticket], 16		\n"
+		"	andi	%[now_serving], %[ticket], 0xffff	\n"
+		"	bne	%[my_ticket], %[now_serving], 3f	\n"
+		"	 addu	%[ticket], %[ticket], %[inc]		\n"
+		"	sc	%[ticket], %[ticket_ptr]		\n"
+		"	beqz	%[ticket], 1b				\n"
+		"	 li	%[ticket], 1				\n"
+		"2:							\n"
+		"	.subsection 2					\n"
+		"3:	b	2b					\n"
+		"	 li	%[ticket], 0				\n"
+		"	.previous					\n"
+		"	.set pop					\n"
+		: [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
+		  [ticket] "=&r" (tmp),
+		  [my_ticket] "=&r" (tmp2),
+		  [now_serving] "=&r" (tmp3)
+		: [inc] "r" (inc));
 	} else {
 		__asm__ __volatile__ (
 		"	.set push		# arch_spin_trylock	\n"
@@ -258,6 +319,19 @@ static inline void arch_read_lock(arch_rwlock_t *rw)
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
+	} else if (LOONGSON_LLSC_WAR) {
+		do {
+			__asm__ __volatile__(
+			"1:			# arch_read_lock	\n"
+			__WEAK_LLSC_MB
+			"	ll	%1, %2				\n"
+			"	bltz	%1, 1b				\n"
+			"	 addu	%1, 1				\n"
+			"2:	sc	%1, %0				\n"
+			: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
+			: GCC_OFF_SMALL_ASM() (rw->lock)
+			: "memory");
+		} while (unlikely(!tmp));
 	} else {
 		do {
 			__asm__ __volatile__(
@@ -289,6 +363,20 @@ static inline void arch_read_unlock(arch_rwlock_t *rw)
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
+	} else if (LOONGSON_LLSC_WAR) {
+		do {
+			__asm__ __volatile__(
+			"1:			# arch_read_unlock	\n"
+			__WEAK_LLSC_MB
+			"	ll	%1, %2				\n"
+			"	addiu	%1, -1				\n"
+			"	sc	%1, %0				\n"
+			: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
+			: GCC_OFF_SMALL_ASM() (rw->lock)
+			: "memory");
+		} while (unlikely(!tmp));
+
+		smp_llsc_mb();
 	} else {
 		do {
 			__asm__ __volatile__(
@@ -319,6 +407,19 @@ static inline void arch_write_lock(arch_rwlock_t *rw)
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
+	} else if (LOONGSON_LLSC_WAR) {
+		do {
+			__asm__ __volatile__(
+			"1:			# arch_write_lock	\n"
+			__WEAK_LLSC_MB
+			"	ll	%1, %2				\n"
+			"	bnez	%1, 1b				\n"
+			"	 lui	%1, 0x8000			\n"
+			"2:	sc	%1, %0				\n"
+			: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp)
+			: GCC_OFF_SMALL_ASM() (rw->lock)
+			: "memory");
+		} while (unlikely(!tmp));
 	} else {
 		do {
 			__asm__ __volatile__(
@@ -345,6 +446,8 @@ static inline void arch_write_unlock(arch_rwlock_t *rw)
 	: "=m" (rw->lock)
 	: "m" (rw->lock)
 	: "memory");
+
+	nudge_writes();
 }
 
 static inline int arch_read_trylock(arch_rwlock_t *rw)
@@ -369,6 +472,27 @@ static inline int arch_read_trylock(arch_rwlock_t *rw)
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp), "=&r" (ret)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
+	} else if (LOONGSON_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	noreorder	# arch_read_trylock	\n"
+		"	li	%2, 0					\n"
+		"1:							\n"
+		__WEAK_LLSC_MB
+		"	ll	%1, %3					\n"
+		"	bltz	%1, 2f					\n"
+		"	 addu	%1, 1					\n"
+		"	sc	%1, %0					\n"
+		"	beqz	%1, 1b					\n"
+		"	 nop						\n"
+		"	.set	reorder					\n"
+		__WEAK_LLSC_MB
+		"	li	%2, 1					\n"
+		"2:							\n"
+		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp), "=&r" (ret)
+		: GCC_OFF_SMALL_ASM() (rw->lock)
+		: "memory");
+
+		smp_llsc_mb();
 	} else {
 		__asm__ __volatile__(
 		"	.set	noreorder	# arch_read_trylock	\n"
@@ -413,6 +537,24 @@ static inline int arch_write_trylock(arch_rwlock_t *rw)
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp), "=&r" (ret)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
+	} else if (LOONGSON_LLSC_WAR) {
+		do {
+			__asm__ __volatile__(
+			__WEAK_LLSC_MB
+			"	ll	%1, %3	# arch_write_trylock	\n"
+			"	li	%2, 0				\n"
+			"	bnez	%1, 2f				\n"
+			"	lui	%1, 0x8000			\n"
+			"	sc	%1, %0				\n"
+			"	li	%2, 1				\n"
+			"2:						\n"
+			: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp),
+			  "=&r" (ret)
+			: GCC_OFF_SMALL_ASM() (rw->lock)
+			: "memory");
+		} while (unlikely(!tmp));
+
+		smp_llsc_mb();
 	} else {
 		do {
 			__asm__ __volatile__(
diff --git a/arch/mips/include/asm/war.h b/arch/mips/include/asm/war.h
index 9344e24..2fe696a 100644
--- a/arch/mips/include/asm/war.h
+++ b/arch/mips/include/asm/war.h
@@ -227,6 +227,14 @@
 #endif
 
 /*
+ * On the Loongson-2G/2H/3A/3B there is a bug that ll / sc and lld / scd is
+ * very weak ordering.
+ */
+#ifndef LOONGSON_LLSC_WAR
+#error Check setting of LOONGSON_LLSC_WAR for your platform
+#endif
+
+/*
  * 34K core erratum: "Problems Executing the TLBR Instruction"
  */
 #ifndef MIPS34K_MISSED_ITLB_WAR
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 58c6f63..8dd8cb8 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -128,6 +128,40 @@ static inline int mips_atomic_set(unsigned long addr, unsigned long new)
 		  [new] "r" (new),
 		  [efault] "i" (-EFAULT)
 		: "memory");
+	} else if (cpu_has_llsc && LOONGSON_LLSC_WAR) {
+		__asm__ __volatile__ (
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
+		"	li	%[err], 0				\n"
+		"1:							\n"
+		__WEAK_LLSC_MB
+		"	ll	%[old], (%[addr])			\n"
+		"	move	%[tmp], %[new]				\n"
+		"2:	sc	%[tmp], (%[addr])			\n"
+		"	beqz	%[tmp], 4f				\n"
+		"3:							\n"
+		"	.insn						\n"
+		"	.subsection 2					\n"
+		"4:	b	1b					\n"
+		"	.previous					\n"
+		"							\n"
+		"	.section .fixup,\"ax\"				\n"
+		"5:	li	%[err], %[efault]			\n"
+		"	j	3b					\n"
+		"	.previous					\n"
+		"	.section __ex_table,\"a\"			\n"
+		"	"STR(PTR)"	(1b + 4), 5b			\n"
+		"	"STR(PTR)"	(2b + 0), 5b			\n"
+		"	.previous					\n"
+		"	.set	mips0					\n"
+		: [old] "=&r" (old),
+		  [err] "=&r" (err),
+		  [tmp] "=&r" (tmp)
+		: [addr] "r" (addr),
+		  [new] "r" (new),
+		  [efault] "i" (-EFAULT)
+		: "memory");
+
+		smp_llsc_mb();
 	} else if (cpu_has_llsc) {
 		__asm__ __volatile__ (
 		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform
index 0fce460..3700dcf 100644
--- a/arch/mips/loongson64/Platform
+++ b/arch/mips/loongson64/Platform
@@ -23,6 +23,9 @@ ifdef CONFIG_CPU_LOONGSON2F_WORKAROUNDS
 endif
 
 cflags-$(CONFIG_CPU_LOONGSON3)	+= -Wa,--trap
+ifneq ($(call as-option,-Wa$(comma)-mfix-loongson3-llsc,),)
+  cflags-$(CONFIG_CPU_LOONGSON3) += -Wa$(comma)-mno-fix-loongson3-llsc
+endif
 #
 # binutils from v2.25 on and gcc starting from v4.9.0 treat -march=loongson3a
 # as MIPS64 R2; older versions as just R1.  This leaves the possibility open
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index ed1c529..2ed9a88 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -92,6 +92,11 @@ static inline int __maybe_unused r10000_llsc_war(void)
 	return R10000_LLSC_WAR;
 }
 
+static inline int __maybe_unused loongson_llsc_war(void)
+{
+       return LOONGSON_LLSC_WAR;
+}
+
 static int use_bbit_insns(void)
 {
 	switch (current_cpu_type()) {
@@ -936,6 +941,8 @@ build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
 		 * to mimic that here by taking a load/istream page
 		 * fault.
 		 */
+		if (loongson_llsc_war())
+			uasm_i_sync(p, 0);
 		UASM_i_LA(p, ptr, (unsigned long)tlb_do_page_fault_0);
 		uasm_i_jr(p, ptr);
 
@@ -1561,6 +1568,8 @@ static void build_loongson3_tlb_refill_handler(void)
 
 	if (check_for_high_segbits) {
 		uasm_l_large_segbits_fault(&l, p);
+		if (loongson_llsc_war())
+			uasm_i_sync(&p, 0);
 		UASM_i_LA(&p, K1, (unsigned long)tlb_do_page_fault_0);
 		uasm_i_jr(&p, K1);
 		uasm_i_nop(&p);
@@ -1661,6 +1670,8 @@ static void
 iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)
 {
 #ifdef CONFIG_SMP
+	if (loongson_llsc_war())
+		uasm_i_sync(p, 0);
 # ifdef CONFIG_PHYS_ADDR_T_64BIT
 	if (cpu_has_64bits)
 		uasm_i_lld(p, pte, 0, ptr);
@@ -2242,6 +2253,8 @@ static void build_r4000_tlb_load_handler(void)
 #endif
 
 	uasm_l_nopage_tlbl(&l, p);
+	if (loongson_llsc_war())
+		uasm_i_sync(&p, 0);
 	build_restore_work_registers(&p);
 #ifdef CONFIG_CPU_MICROMIPS
 	if ((unsigned long)tlb_do_page_fault_0 & 1) {
@@ -2297,6 +2310,8 @@ static void build_r4000_tlb_store_handler(void)
 #endif
 
 	uasm_l_nopage_tlbs(&l, p);
+	if (loongson_llsc_war())
+		uasm_i_sync(&p, 0);
 	build_restore_work_registers(&p);
 #ifdef CONFIG_CPU_MICROMIPS
 	if ((unsigned long)tlb_do_page_fault_1 & 1) {
@@ -2353,6 +2368,8 @@ static void build_r4000_tlb_modify_handler(void)
 #endif
 
 	uasm_l_nopage_tlbm(&l, p);
+	if (loongson_llsc_war())
+		uasm_i_sync(&p, 0);
 	build_restore_work_registers(&p);
 #ifdef CONFIG_CPU_MICROMIPS
 	if ((unsigned long)tlb_do_page_fault_1 & 1) {
-- 
2.7.0

Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[James Hogan]

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On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
> diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
> index 0ab176b..e0002c58 100644
> --- a/arch/mips/include/asm/atomic.h
> +++ b/arch/mips/include/asm/atomic.h
> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i, atomic_t * v)			      \
>  		"	.set	mips0					\n"   \
>  		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
>  		: "Ir" (i));						      \
> +	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
> +		int temp;						      \
> +									      \
> +		do {							      \
> +			__asm__ __volatile__(				      \
> +			"	.set	"MIPS_ISA_LEVEL"		\n"   \
> +			__WEAK_LLSC_MB					      \
> +			"	ll	%0, %1		# atomic_" #op "\n"   \
> +			"	" #asm_op " %0, %2			\n"   \
> +			"	sc	%0, %1				\n"   \
> +			"	.set	mips0				\n"   \
> +			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
> +			: "Ir" (i));					      \
> +		} while (unlikely(!temp));				      \

Can loongson use the common versions of all these bits of assembly by
adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
before the asm?

It would save a lot of duplication, avoid potential bitrot and
divergence, and make the patch much easier to review.

Cheers
James

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Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[James Hogan]

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On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
> diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
> index 0ab176b..e0002c58 100644
> --- a/arch/mips/include/asm/atomic.h
> +++ b/arch/mips/include/asm/atomic.h
> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i, atomic_t * v)			      \
>  		"	.set	mips0					\n"   \
>  		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
>  		: "Ir" (i));						      \
> +	} else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {		      \
> +		int temp;						      \
> +									      \
> +		do {							      \
> +			__asm__ __volatile__(				      \
> +			"	.set	"MIPS_ISA_LEVEL"		\n"   \
> +			__WEAK_LLSC_MB					      \
> +			"	ll	%0, %1		# atomic_" #op "\n"   \
> +			"	" #asm_op " %0, %2			\n"   \
> +			"	sc	%0, %1				\n"   \
> +			"	.set	mips0				\n"   \
> +			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
> +			: "Ir" (i));					      \
> +		} while (unlikely(!temp));				      \

Can loongson use the common versions of all these bits of assembly by
adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
before the asm?

It would save a lot of duplication, avoid potential bitrot and
divergence, and make the patch much easier to review.

Cheers
James

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Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[Huacai Chen]

Hi, James,

smp_mb__before_llsc() can not be used in all cases, e.g., in
arch/mips/include/asm/spinlock.h and other similar cases which has a
label before ll/lld. So, I think it is better to keep it as is to keep
consistency.

Huacai

On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com> wrote:
> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
>> diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
>> index 0ab176b..e0002c58 100644
>> --- a/arch/mips/include/asm/atomic.h
>> +++ b/arch/mips/include/asm/atomic.h
>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i, atomic_t * v)                          \
>>               "       .set    mips0                                   \n"   \
>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)          \
>>               : "Ir" (i));                                                  \
>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {                   \
>> +             int temp;                                                     \
>> +                                                                           \
>> +             do {                                                          \
>> +                     __asm__ __volatile__(                                 \
>> +                     "       .set    "MIPS_ISA_LEVEL"                \n"   \
>> +                     __WEAK_LLSC_MB                                        \
>> +                     "       ll      %0, %1          # atomic_" #op "\n"   \
>> +                     "       " #asm_op " %0, %2                      \n"   \
>> +                     "       sc      %0, %1                          \n"   \
>> +                     "       .set    mips0                           \n"   \
>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
>> +                     : "Ir" (i));                                          \
>> +             } while (unlikely(!temp));                                    \
>
> Can loongson use the common versions of all these bits of assembly by
> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
> before the asm?
>
> It would save a lot of duplication, avoid potential bitrot and
> divergence, and make the patch much easier to review.
>
> Cheers
> James

Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[James Hogan]

On 24 June 2017 09:55:14 BST, Huacai Chen <chenhc@lemote.com> wrote:
>Hi, James,
>
>smp_mb__before_llsc() can not be used in all cases, e.g., in
>arch/mips/include/asm/spinlock.h and other similar cases which has a
>label before ll/lld. So, I think it is better to keep it as is to keep
>consistency.

I know. I didn't mean use smp_mb_before_llsc directly, i just meant use something similar directly before the ll that would expand to nothing on non loongson kernels and still avoid the mass duplication of inline asm which leads to divergence, bitrot, and maintenance problems.

cheers
James

>
>Huacai
>
>On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com>
>wrote:
>> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
>>> diff --git a/arch/mips/include/asm/atomic.h
>b/arch/mips/include/asm/atomic.h
>>> index 0ab176b..e0002c58 100644
>>> --- a/arch/mips/include/asm/atomic.h
>>> +++ b/arch/mips/include/asm/atomic.h
>>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i,
>atomic_t * v)                          \
>>>               "       .set    mips0                                 
> \n"   \
>>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)  
>       \
>>>               : "Ir" (i));                                          
>       \
>>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {           
>       \
>>> +             int temp;                                             
>       \
>>> +                                                                   
>       \
>>> +             do {                                                  
>       \
>>> +                     __asm__ __volatile__(                         
>       \
>>> +                     "       .set    "MIPS_ISA_LEVEL"              
> \n"   \
>>> +                     __WEAK_LLSC_MB                                
>       \
>>> +                     "       ll      %0, %1          # atomic_" #op
>"\n"   \
>>> +                     "       " #asm_op " %0, %2                    
> \n"   \
>>> +                     "       sc      %0, %1                        
> \n"   \
>>> +                     "       .set    mips0                         
> \n"   \
>>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM()
>(v->counter)      \
>>> +                     : "Ir" (i));                                  
>       \
>>> +             } while (unlikely(!temp));                            
>       \
>>
>> Can loongson use the common versions of all these bits of assembly by
>> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
>> before the asm?
>>
>> It would save a lot of duplication, avoid potential bitrot and
>> divergence, and make the patch much easier to review.
>>
>> Cheers
>> James


--
James Hogan

Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[James Hogan]

On 24 June 2017 09:55:14 BST, Huacai Chen <chenhc@lemote.com> wrote:
>Hi, James,
>
>smp_mb__before_llsc() can not be used in all cases, e.g., in
>arch/mips/include/asm/spinlock.h and other similar cases which has a
>label before ll/lld. So, I think it is better to keep it as is to keep
>consistency.

I know. I didn't mean use smp_mb_before_llsc directly, i just meant use something similar directly before the ll that would expand to nothing on non loongson kernels and still avoid the mass duplication of inline asm which leads to divergence, bitrot, and maintenance problems.

cheers
James

>
>Huacai
>
>On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com>
>wrote:
>> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
>>> diff --git a/arch/mips/include/asm/atomic.h
>b/arch/mips/include/asm/atomic.h
>>> index 0ab176b..e0002c58 100644
>>> --- a/arch/mips/include/asm/atomic.h
>>> +++ b/arch/mips/include/asm/atomic.h
>>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i,
>atomic_t * v)                          \
>>>               "       .set    mips0                                 
> \n"   \
>>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)  
>       \
>>>               : "Ir" (i));                                          
>       \
>>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {           
>       \
>>> +             int temp;                                             
>       \
>>> +                                                                   
>       \
>>> +             do {                                                  
>       \
>>> +                     __asm__ __volatile__(                         
>       \
>>> +                     "       .set    "MIPS_ISA_LEVEL"              
> \n"   \
>>> +                     __WEAK_LLSC_MB                                
>       \
>>> +                     "       ll      %0, %1          # atomic_" #op
>"\n"   \
>>> +                     "       " #asm_op " %0, %2                    
> \n"   \
>>> +                     "       sc      %0, %1                        
> \n"   \
>>> +                     "       .set    mips0                         
> \n"   \
>>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM()
>(v->counter)      \
>>> +                     : "Ir" (i));                                  
>       \
>>> +             } while (unlikely(!temp));                            
>       \
>>
>> Can loongson use the common versions of all these bits of assembly by
>> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
>> before the asm?
>>
>> It would save a lot of duplication, avoid potential bitrot and
>> divergence, and make the patch much easier to review.
>>
>> Cheers
>> James


--
James Hogan

Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[Huacai Chen]

You are right, but it seems like __WEAK_LLSC_MB is already the best
name for this case. Maybe I define a macro named __VERY_WEAK_LLSC_MB
to expand a "sync" on Loongson?

Huacai

On Sat, Jun 24, 2017 at 5:02 PM, James Hogan <james.hogan@imgtec.com> wrote:
> On 24 June 2017 09:55:14 BST, Huacai Chen <chenhc@lemote.com> wrote:
>>Hi, James,
>>
>>smp_mb__before_llsc() can not be used in all cases, e.g., in
>>arch/mips/include/asm/spinlock.h and other similar cases which has a
>>label before ll/lld. So, I think it is better to keep it as is to keep
>>consistency.
>
> I know. I didn't mean use smp_mb_before_llsc directly, i just meant use something similar directly before the ll that would expand to nothing on non loongson kernels and still avoid the mass duplication of inline asm which leads to divergence, bitrot, and maintenance problems.
>
> cheers
> James
>
>>
>>Huacai
>>
>>On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com>
>>wrote:
>>> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
>>>> diff --git a/arch/mips/include/asm/atomic.h
>>b/arch/mips/include/asm/atomic.h
>>>> index 0ab176b..e0002c58 100644
>>>> --- a/arch/mips/include/asm/atomic.h
>>>> +++ b/arch/mips/include/asm/atomic.h
>>>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i,
>>atomic_t * v)                          \
>>>>               "       .set    mips0
>> \n"   \
>>>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)
>>       \
>>>>               : "Ir" (i));
>>       \
>>>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
>>       \
>>>> +             int temp;
>>       \
>>>> +
>>       \
>>>> +             do {
>>       \
>>>> +                     __asm__ __volatile__(
>>       \
>>>> +                     "       .set    "MIPS_ISA_LEVEL"
>> \n"   \
>>>> +                     __WEAK_LLSC_MB
>>       \
>>>> +                     "       ll      %0, %1          # atomic_" #op
>>"\n"   \
>>>> +                     "       " #asm_op " %0, %2
>> \n"   \
>>>> +                     "       sc      %0, %1
>> \n"   \
>>>> +                     "       .set    mips0
>> \n"   \
>>>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM()
>>(v->counter)      \
>>>> +                     : "Ir" (i));
>>       \
>>>> +             } while (unlikely(!temp));
>>       \
>>>
>>> Can loongson use the common versions of all these bits of assembly by
>>> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
>>> before the asm?
>>>
>>> It would save a lot of duplication, avoid potential bitrot and
>>> divergence, and make the patch much easier to review.
>>>
>>> Cheers
>>> James
>
>
> --
> James Hogan
>

Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[James Hogan]

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Hi Huacai,

On Sat, Jun 24, 2017 at 05:23:52PM +0800, Huacai Chen wrote:
> You are right, but it seems like __WEAK_LLSC_MB is already the best
> name for this case. Maybe I define a macro named __VERY_WEAK_LLSC_MB
> to expand a "sync" on Loongson?

I suppose so.

Can you clarify what very weak ordering means in this context? I.e. in
what case is it insufficient to have the sync before the label rather
than before every ll in the retry loop?

Cheers
James

> 
> Huacai
> 
> On Sat, Jun 24, 2017 at 5:02 PM, James Hogan <james.hogan@imgtec.com> wrote:
> > On 24 June 2017 09:55:14 BST, Huacai Chen <chenhc@lemote.com> wrote:
> >>Hi, James,
> >>
> >>smp_mb__before_llsc() can not be used in all cases, e.g., in
> >>arch/mips/include/asm/spinlock.h and other similar cases which has a
> >>label before ll/lld. So, I think it is better to keep it as is to keep
> >>consistency.
> >
> > I know. I didn't mean use smp_mb_before_llsc directly, i just meant use something similar directly before the ll that would expand to nothing on non loongson kernels and still avoid the mass duplication of inline asm which leads to divergence, bitrot, and maintenance problems.
> >
> > cheers
> > James
> >
> >>
> >>Huacai
> >>
> >>On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com>
> >>wrote:
> >>> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
> >>>> diff --git a/arch/mips/include/asm/atomic.h
> >>b/arch/mips/include/asm/atomic.h
> >>>> index 0ab176b..e0002c58 100644
> >>>> --- a/arch/mips/include/asm/atomic.h
> >>>> +++ b/arch/mips/include/asm/atomic.h
> >>>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i,
> >>atomic_t * v)                          \
> >>>>               "       .set    mips0
> >> \n"   \
> >>>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)
> >>       \
> >>>>               : "Ir" (i));
> >>       \
> >>>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
> >>       \
> >>>> +             int temp;
> >>       \
> >>>> +
> >>       \
> >>>> +             do {
> >>       \
> >>>> +                     __asm__ __volatile__(
> >>       \
> >>>> +                     "       .set    "MIPS_ISA_LEVEL"
> >> \n"   \
> >>>> +                     __WEAK_LLSC_MB
> >>       \
> >>>> +                     "       ll      %0, %1          # atomic_" #op
> >>"\n"   \
> >>>> +                     "       " #asm_op " %0, %2
> >> \n"   \
> >>>> +                     "       sc      %0, %1
> >> \n"   \
> >>>> +                     "       .set    mips0
> >> \n"   \
> >>>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM()
> >>(v->counter)      \
> >>>> +                     : "Ir" (i));
> >>       \
> >>>> +             } while (unlikely(!temp));
> >>       \
> >>>
> >>> Can loongson use the common versions of all these bits of assembly by
> >>> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
> >>> before the asm?
> >>>
> >>> It would save a lot of duplication, avoid potential bitrot and
> >>> divergence, and make the patch much easier to review.
> >>>
> >>> Cheers
> >>> James
> >
> >
> > --
> > James Hogan
> >

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Re: [PATCH V7 9/9] MIPS: Loongson: Introduce and use LOONGSON_LLSC_WAR

[Huacai Chen]

OK, I have reworked patch 8 and patch 9.

Huacai

On Mon, Jun 26, 2017 at 4:26 PM, James Hogan <james.hogan@imgtec.com> wrote:
> Hi Huacai,
>
> On Sat, Jun 24, 2017 at 05:23:52PM +0800, Huacai Chen wrote:
>> You are right, but it seems like __WEAK_LLSC_MB is already the best
>> name for this case. Maybe I define a macro named __VERY_WEAK_LLSC_MB
>> to expand a "sync" on Loongson?
>
> I suppose so.
>
> Can you clarify what very weak ordering means in this context? I.e. in
> what case is it insufficient to have the sync before the label rather
> than before every ll in the retry loop?
>
> Cheers
> James
>
>>
>> Huacai
>>
>> On Sat, Jun 24, 2017 at 5:02 PM, James Hogan <james.hogan@imgtec.com> wrote:
>> > On 24 June 2017 09:55:14 BST, Huacai Chen <chenhc@lemote.com> wrote:
>> >>Hi, James,
>> >>
>> >>smp_mb__before_llsc() can not be used in all cases, e.g., in
>> >>arch/mips/include/asm/spinlock.h and other similar cases which has a
>> >>label before ll/lld. So, I think it is better to keep it as is to keep
>> >>consistency.
>> >
>> > I know. I didn't mean use smp_mb_before_llsc directly, i just meant use something similar directly before the ll that would expand to nothing on non loongson kernels and still avoid the mass duplication of inline asm which leads to divergence, bitrot, and maintenance problems.
>> >
>> > cheers
>> > James
>> >
>> >>
>> >>Huacai
>> >>
>> >>On Fri, Jun 23, 2017 at 10:54 PM, James Hogan <james.hogan@imgtec.com>
>> >>wrote:
>> >>> On Thu, Jun 22, 2017 at 11:06:56PM +0800, Huacai Chen wrote:
>> >>>> diff --git a/arch/mips/include/asm/atomic.h
>> >>b/arch/mips/include/asm/atomic.h
>> >>>> index 0ab176b..e0002c58 100644
>> >>>> --- a/arch/mips/include/asm/atomic.h
>> >>>> +++ b/arch/mips/include/asm/atomic.h
>> >>>> @@ -56,6 +56,22 @@ static __inline__ void atomic_##op(int i,
>> >>atomic_t * v)                          \
>> >>>>               "       .set    mips0
>> >> \n"   \
>> >>>>               : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)
>> >>       \
>> >>>>               : "Ir" (i));
>> >>       \
>> >>>> +     } else if (kernel_uses_llsc && LOONGSON_LLSC_WAR) {
>> >>       \
>> >>>> +             int temp;
>> >>       \
>> >>>> +
>> >>       \
>> >>>> +             do {
>> >>       \
>> >>>> +                     __asm__ __volatile__(
>> >>       \
>> >>>> +                     "       .set    "MIPS_ISA_LEVEL"
>> >> \n"   \
>> >>>> +                     __WEAK_LLSC_MB
>> >>       \
>> >>>> +                     "       ll      %0, %1          # atomic_" #op
>> >>"\n"   \
>> >>>> +                     "       " #asm_op " %0, %2
>> >> \n"   \
>> >>>> +                     "       sc      %0, %1
>> >> \n"   \
>> >>>> +                     "       .set    mips0
>> >> \n"   \
>> >>>> +                     : "=&r" (temp), "+" GCC_OFF_SMALL_ASM()
>> >>(v->counter)      \
>> >>>> +                     : "Ir" (i));
>> >>       \
>> >>>> +             } while (unlikely(!temp));
>> >>       \
>> >>>
>> >>> Can loongson use the common versions of all these bits of assembly by
>> >>> adding a LOONGSON_LLSC_WAR dependent smp_mb__before_llsc()-like macro
>> >>> before the asm?
>> >>>
>> >>> It would save a lot of duplication, avoid potential bitrot and
>> >>> divergence, and make the patch much easier to review.
>> >>>
>> >>> Cheers
>> >>> James
>> >
>> >
>> > --
>> > James Hogan
>> >