From 1e820da3c9af4f5771d2ad47099919429b906ac6 Mon Sep 17 00:00:00 2001 From: Huacai Chen Date: Thu, 3 Mar 2016 09:45:13 +0800 Subject: [PATCH] MIPS: Loongson-3: Introduce CONFIG_LOONGSON3_ENHANCEMENT New Loongson 3 CPU (since Loongson-3A R2, as opposed to Loongson-3A R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPv2 ASE, User Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer), Fast TLB refill support, etc. This patch introduce a config option, CONFIG_LOONGSON3_ENHANCEMENT, to enable those enhancements which are not probed at run time. If you want a generic kernel to run on all Loongson 3 machines, please say 'N' here. If you want a high-performance kernel to run on new Loongson 3 machines only, please say 'Y' here. Some additional explanations: 1) SFB locates between core and L1 cache, it causes memory access out of order, so writel/outl (and other similar functions) need a I/O reorder barrier. 2) Loongson 3 has a bug that di instruction can not save the irqflag, so arch_local_irq_save() is modified. Since CPU_MIPSR2 is selected by CONFIG_LOONGSON3_ENHANCEMENT, generic kernel doesn't use ei/di at all. 3) CPU_HAS_PREFETCH is selected by CONFIG_LOONGSON3_ENHANCEMENT, so MIPS_CPU_PREFETCH (used by uasm) probing is also put in this patch. Signed-off-by: Huacai Chen Cc: Aurelien Jarno Cc: Steven J . Hill Cc: Fuxin Zhang Cc: Zhangjin Wu Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12755/ Signed-off-by: Ralf Baechle --- arch/mips/Kconfig | 18 ++++++++++++++++++ arch/mips/include/asm/hazards.h | 7 ++++--- arch/mips/include/asm/io.h | 10 +++++----- arch/mips/include/asm/irqflags.h | 5 +++++ .../asm/mach-loongson64/kernel-entry-init.h | 12 ++++++++++++ arch/mips/mm/c-r4k.c | 2 ++ arch/mips/mm/page.c | 9 +++++++++ 7 files changed, 55 insertions(+), 8 deletions(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index adcc97ea4392..d5c3621f0dd1 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1360,6 +1360,24 @@ config CPU_LOONGSON3 The Loongson 3 processor implements the MIPS64R2 instruction set with many extensions. +config LOONGSON3_ENHANCEMENT + bool "New Loongson 3 CPU Enhancements" + default n + select CPU_MIPSR2 + select CPU_HAS_PREFETCH + depends on CPU_LOONGSON3 + help + New Loongson 3 CPU (since Loongson-3A R2, as opposed to Loongson-3A + R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as + FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPv2 ASE, User + Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer), + Fast TLB refill support, etc. + + This option enable those enhancements which are not probed at run + time. If you want a generic kernel to run on all Loongson 3 machines, + please say 'N' here. If you want a high-performance kernel to run on + new Loongson 3 machines only, please say 'Y' here. + config CPU_LOONGSON2E bool "Loongson 2E" depends on SYS_HAS_CPU_LOONGSON2E diff --git a/arch/mips/include/asm/hazards.h b/arch/mips/include/asm/hazards.h index 7b99efd31074..dbb1eb6e284f 100644 --- a/arch/mips/include/asm/hazards.h +++ b/arch/mips/include/asm/hazards.h @@ -22,7 +22,8 @@ /* * TLB hazards */ -#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) && !defined(CONFIG_CPU_CAVIUM_OCTEON) +#if (defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)) && \ + !defined(CONFIG_CPU_CAVIUM_OCTEON) && !defined(CONFIG_LOONGSON3_ENHANCEMENT) /* * MIPSR2 defines ehb for hazard avoidance @@ -155,8 +156,8 @@ do { \ } while (0) #elif defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_CPU_CAVIUM_OCTEON) || \ - defined(CONFIG_CPU_LOONGSON2) || defined(CONFIG_CPU_R10000) || \ - defined(CONFIG_CPU_R5500) || defined(CONFIG_CPU_XLR) + defined(CONFIG_CPU_LOONGSON2) || defined(CONFIG_LOONGSON3_ENHANCEMENT) || \ + defined(CONFIG_CPU_R10000) || defined(CONFIG_CPU_R5500) || defined(CONFIG_CPU_XLR) /* * R10000 rocks - all hazards handled in hardware, so this becomes a nobrainer. diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 2b4dc7ad53b8..ecabc00c1e66 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -304,10 +304,10 @@ static inline void iounmap(const volatile void __iomem *addr) #undef __IS_KSEG1 } -#ifdef CONFIG_CPU_CAVIUM_OCTEON -#define war_octeon_io_reorder_wmb() wmb() +#if defined(CONFIG_CPU_CAVIUM_OCTEON) || defined(CONFIG_LOONGSON3_ENHANCEMENT) +#define war_io_reorder_wmb() wmb() #else -#define war_octeon_io_reorder_wmb() do { } while (0) +#define war_io_reorder_wmb() do { } while (0) #endif #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq) \ @@ -318,7 +318,7 @@ static inline void pfx##write##bwlq(type val, \ volatile type *__mem; \ type __val; \ \ - war_octeon_io_reorder_wmb(); \ + war_io_reorder_wmb(); \ \ __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \ \ @@ -387,7 +387,7 @@ static inline void pfx##out##bwlq##p(type val, unsigned long port) \ volatile type *__addr; \ type __val; \ \ - war_octeon_io_reorder_wmb(); \ + war_io_reorder_wmb(); \ \ __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \ \ diff --git a/arch/mips/include/asm/irqflags.h b/arch/mips/include/asm/irqflags.h index 65c351e328cc..9d3610be2323 100644 --- a/arch/mips/include/asm/irqflags.h +++ b/arch/mips/include/asm/irqflags.h @@ -41,7 +41,12 @@ static inline unsigned long arch_local_irq_save(void) " .set push \n" " .set reorder \n" " .set noat \n" +#if defined(CONFIG_CPU_LOONGSON3) + " mfc0 %[flags], $12 \n" + " di \n" +#else " di %[flags] \n" +#endif " andi %[flags], 1 \n" " " __stringify(__irq_disable_hazard) " \n" " .set pop \n" diff --git a/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h b/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h index da83482ff0b9..8393bc548987 100644 --- a/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h +++ b/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h @@ -26,6 +26,12 @@ mfc0 t0, $5, 1 or t0, (0x1 << 29) mtc0 t0, $5, 1 +#ifdef CONFIG_LOONGSON3_ENHANCEMENT + /* Enable STFill Buffer */ + mfc0 t0, $16, 6 + or t0, 0x100 + mtc0 t0, $16, 6 +#endif _ehb .set pop #endif @@ -46,6 +52,12 @@ mfc0 t0, $5, 1 or t0, (0x1 << 29) mtc0 t0, $5, 1 +#ifdef CONFIG_LOONGSON3_ENHANCEMENT + /* Enable STFill Buffer */ + mfc0 t0, $16, 6 + or t0, 0x100 + mtc0 t0, $16, 6 +#endif _ehb .set pop #endif diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c index 3415d3e2a63b..d73b304cfe8a 100644 --- a/arch/mips/mm/c-r4k.c +++ b/arch/mips/mm/c-r4k.c @@ -1161,6 +1161,8 @@ static void probe_pcache(void) c->dcache.ways * c->dcache.linesz; c->dcache.waybit = 0; + if ((prid & PRID_REV_MASK) >= PRID_REV_LOONGSON3A_R2) + c->options |= MIPS_CPU_PREFETCH; break; case CPU_CAVIUM_OCTEON3: diff --git a/arch/mips/mm/page.c b/arch/mips/mm/page.c index 885d73ffd6fb..c41953ca6605 100644 --- a/arch/mips/mm/page.c +++ b/arch/mips/mm/page.c @@ -188,6 +188,15 @@ static void set_prefetch_parameters(void) } break; + case CPU_LOONGSON3: + /* Loongson-3 only support the Pref_Load/Pref_Store. */ + pref_bias_clear_store = 128; + pref_bias_copy_load = 128; + pref_bias_copy_store = 128; + pref_src_mode = Pref_Load; + pref_dst_mode = Pref_Store; + break; + default: pref_bias_clear_store = 128; pref_bias_copy_load = 256; -- 2.39.5