From b15cb0bfe8c77002ab639378b548f2c817283315 Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Wed, 11 Mar 2020 15:00:43 +0300 Subject: ARC: CACHE: add support for SL$ disable Since version 3.0 ARC HS supports SL$ (L2 system level cache) disable. So add support for SL$ disable/enable to code. Signed-off-by: Eugeniy Paltsev Signed-off-by: Alexey Brodkin --- arch/arc/include/asm/cache.h | 7 +++ arch/arc/lib/cache.c | 114 ++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 114 insertions(+), 7 deletions(-) (limited to 'arch/arc') diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h index 0fdcf2d2dd..ab61846b5a 100644 --- a/arch/arc/include/asm/cache.h +++ b/arch/arc/include/asm/cache.h @@ -40,6 +40,13 @@ static const inline int is_ioc_enabled(void) return IS_ENABLED(CONFIG_ARC_DBG_IOC_ENABLE); } +/* + * We export SLC control functions to use them in platform configuration code. + * They maust not be used in any generic code! + */ +void slc_enable(void); +void slc_disable(void); + #endif /* __ASSEMBLY__ */ #endif /* __ASM_ARC_CACHE_H */ diff --git a/arch/arc/lib/cache.c b/arch/arc/lib/cache.c index 1340776c66..c42723daeb 100644 --- a/arch/arc/lib/cache.c +++ b/arch/arc/lib/cache.c @@ -89,8 +89,7 @@ * * [ NOTE 2 ]: * As of today we only support the following cache configurations on ARC. - * Other configurations may exist in HW (for example, since version 3.0 HS - * supports SL$ (L2 system level cache) disable) but we don't support it in SW. + * Other configurations may exist in HW but we don't support it in SW. * Configuration 1: * ______________________ * | | @@ -120,7 +119,8 @@ * | | * | L2 (SL$) | * |______________________| - * always must be on + * always on (ARCv2, HS < 3.0) + * on/off (ARCv2, HS >= 3.0) * ___|______________|____ * | | * | main memory | @@ -178,6 +178,8 @@ DECLARE_GLOBAL_DATA_PTR; static inlined_cachefunc void __ic_entire_invalidate(void); static inlined_cachefunc void __dc_entire_op(const int cacheop); +static inlined_cachefunc void __slc_entire_op(const int op); +static inline bool ioc_enabled(void); static inline bool pae_exists(void) { @@ -238,6 +240,70 @@ static inlined_cachefunc bool slc_exists(void) return false; } +enum slc_dis_status { + ST_SLC_MISSING = 0, + ST_SLC_NO_DISABLE_CTRL, + ST_SLC_DISABLE_CTRL +}; + +/* + * ARCv1 -> ST_SLC_MISSING + * ARCv2 && SLC absent -> ST_SLC_MISSING + * ARCv2 && SLC exists && SLC version <= 2 -> ST_SLC_NO_DISABLE_CTRL + * ARCv2 && SLC exists && SLC version > 2 -> ST_SLC_DISABLE_CTRL + */ +static inlined_cachefunc enum slc_dis_status slc_disable_supported(void) +{ + if (is_isa_arcv2()) { + union bcr_generic sbcr; + + sbcr.word = read_aux_reg(ARC_BCR_SLC); + if (sbcr.fields.ver == 0) + return ST_SLC_MISSING; + else if (sbcr.fields.ver <= 2) + return ST_SLC_NO_DISABLE_CTRL; + else + return ST_SLC_DISABLE_CTRL; + } + + return ST_SLC_MISSING; +} + +static inlined_cachefunc bool __slc_enabled(void) +{ + return !(read_aux_reg(ARC_AUX_SLC_CTRL) & SLC_CTRL_DIS); +} + +static inlined_cachefunc void __slc_enable(void) +{ + unsigned int ctrl; + + ctrl = read_aux_reg(ARC_AUX_SLC_CTRL); + ctrl &= ~SLC_CTRL_DIS; + write_aux_reg(ARC_AUX_SLC_CTRL, ctrl); +} + +static inlined_cachefunc void __slc_disable(void) +{ + unsigned int ctrl; + + ctrl = read_aux_reg(ARC_AUX_SLC_CTRL); + ctrl |= SLC_CTRL_DIS; + write_aux_reg(ARC_AUX_SLC_CTRL, ctrl); +} + +static inlined_cachefunc bool slc_enabled(void) +{ + enum slc_dis_status slc_status = slc_disable_supported(); + + if (slc_status == ST_SLC_MISSING) + return false; + else if (slc_status == ST_SLC_NO_DISABLE_CTRL) + return true; + else + return __slc_enabled(); +} + static inlined_cachefunc bool slc_data_bypass(void) { /* @@ -247,6 +313,39 @@ static inlined_cachefunc bool slc_data_bypass(void) return !dcache_enabled(); } +void slc_enable(void) +{ + if (slc_disable_supported() != ST_SLC_DISABLE_CTRL) + return; + + if (__slc_enabled()) + return; + + __slc_enable(); +} + +/* TODO: warn if we are not able to disable SLC */ +void slc_disable(void) +{ + if (slc_disable_supported() != ST_SLC_DISABLE_CTRL) + return; + + /* we don't support SLC disabling if we use IOC */ + if (ioc_enabled()) + return; + + if (!__slc_enabled()) + return; + + /* + * We need to flush L1D$ to guarantee that we won't have any + * writeback operations during SLC disabling. + */ + __dc_entire_op(OP_FLUSH); + __slc_entire_op(OP_FLUSH_N_INV); + __slc_disable(); +} + static inline bool ioc_exists(void) { if (is_isa_arcv2()) { @@ -275,7 +374,7 @@ static inlined_cachefunc void __slc_entire_op(const int op) { unsigned int ctrl; - if (!slc_exists()) + if (!slc_enabled()) return; ctrl = read_aux_reg(ARC_AUX_SLC_CTRL); @@ -324,7 +423,7 @@ static void __slc_rgn_op(unsigned long paddr, unsigned long sz, const int op) unsigned int ctrl; unsigned long end; - if (!slc_exists()) + if (!slc_enabled()) return; /* @@ -382,6 +481,9 @@ static void arc_ioc_setup(void) if (!slc_exists()) panic("Try to enable IOC but SLC is not present"); + if (!slc_enabled()) + panic("Try to enable IOC but SLC is disabled"); + /* Unsupported configuration. See [ NOTE 2 ] for more details. */ if (!dcache_enabled()) panic("Try to enable IOC but L1 D$ is disabled"); @@ -517,8 +619,6 @@ void invalidate_icache_all(void) /* * If SL$ is bypassed for data it is used only for instructions, * so we need to invalidate it too. - * TODO: HS 3.0 supports SLC disable so we need to check slc - * enable/disable status here. */ if (is_isa_arcv2() && slc_data_bypass()) __slc_entire_op(OP_INV); -- cgit v1.2.3