From 4d035516921713b41bb279682e53b4fbd5a87232 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Tue, 22 Sep 2015 10:10:54 -0700 Subject: [PATCH] MIPS: Enable L2 prefetching for CM >= 2.5 On systems with CM 2.5 & beyond there may be L2 prefetch units present which are not enabled by default. Detect them, configuring & enabling prefetching when available. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: Leonid Yegoshin Cc: linux-kernel@vger.kernel.org Cc: James Hogan Cc: Markos Chandras Patchwork: https://patchwork.linux-mips.org/patch/11180/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mips-cm.h | 17 +++++++++ arch/mips/mm/sc-mips.c | 61 ++++++++++++++++++++++++++++++++- 2 files changed, 77 insertions(+), 1 deletion(-) diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h index 1f1927ab4269..d66d0e00365b 100644 --- a/arch/mips/include/asm/mips-cm.h +++ b/arch/mips/include/asm/mips-cm.h @@ -195,6 +195,8 @@ BUILD_CM_R_(gic_status, MIPS_CM_GCB_OFS + 0xd0) BUILD_CM_R_(cpc_status, MIPS_CM_GCB_OFS + 0xf0) BUILD_CM_RW(l2_config, MIPS_CM_GCB_OFS + 0x130) BUILD_CM_RW(sys_config2, MIPS_CM_GCB_OFS + 0x150) +BUILD_CM_RW(l2_pft_control, MIPS_CM_GCB_OFS + 0x300) +BUILD_CM_RW(l2_pft_control_b, MIPS_CM_GCB_OFS + 0x308) /* Core Local & Core Other register accessor functions */ BUILD_CM_Cx_RW(reset_release, 0x00) @@ -245,6 +247,7 @@ BUILD_CM_Cx_R_(tcid_8_priority, 0x80) ((minor) << CM_GCR_REV_MINOR_SHF)) #define CM_REV_CM2 CM_ENCODE_REV(6, 0) +#define CM_REV_CM2_5 CM_ENCODE_REV(7, 0) #define CM_REV_CM3 CM_ENCODE_REV(8, 0) /* GCR_ERROR_CAUSE register fields */ @@ -321,6 +324,20 @@ BUILD_CM_Cx_R_(tcid_8_priority, 0x80) #define CM_GCR_SYS_CONFIG2_MAXVPW_SHF 0 #define CM_GCR_SYS_CONFIG2_MAXVPW_MSK (_ULCAST_(0xf) << 0) +/* GCR_L2_PFT_CONTROL register fields */ +#define CM_GCR_L2_PFT_CONTROL_PAGEMASK_SHF 12 +#define CM_GCR_L2_PFT_CONTROL_PAGEMASK_MSK (_ULCAST_(0xfffff) << 12) +#define CM_GCR_L2_PFT_CONTROL_PFTEN_SHF 8 +#define CM_GCR_L2_PFT_CONTROL_PFTEN_MSK (_ULCAST_(0x1) << 8) +#define CM_GCR_L2_PFT_CONTROL_NPFT_SHF 0 +#define CM_GCR_L2_PFT_CONTROL_NPFT_MSK (_ULCAST_(0xff) << 0) + +/* GCR_L2_PFT_CONTROL_B register fields */ +#define CM_GCR_L2_PFT_CONTROL_B_CEN_SHF 8 +#define CM_GCR_L2_PFT_CONTROL_B_CEN_MSK (_ULCAST_(0x1) << 8) +#define CM_GCR_L2_PFT_CONTROL_B_PORTID_SHF 0 +#define CM_GCR_L2_PFT_CONTROL_B_PORTID_MSK (_ULCAST_(0xff) << 0) + /* GCR_Cx_COHERENCE register fields */ #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_SHF 0 #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK (_ULCAST_(0xff) << 0) diff --git a/arch/mips/mm/sc-mips.c b/arch/mips/mm/sc-mips.c index 1755187a6545..3bd0597d9c3d 100644 --- a/arch/mips/mm/sc-mips.c +++ b/arch/mips/mm/sc-mips.c @@ -51,11 +51,69 @@ static void mips_sc_disable(void) /* L2 cache is permanently enabled */ } +static void mips_sc_prefetch_enable(void) +{ + unsigned long pftctl; + + if (mips_cm_revision() < CM_REV_CM2_5) + return; + + /* + * If there is one or more L2 prefetch unit present then enable + * prefetching for both code & data, for all ports. + */ + pftctl = read_gcr_l2_pft_control(); + if (pftctl & CM_GCR_L2_PFT_CONTROL_NPFT_MSK) { + pftctl &= ~CM_GCR_L2_PFT_CONTROL_PAGEMASK_MSK; + pftctl |= PAGE_MASK & CM_GCR_L2_PFT_CONTROL_PAGEMASK_MSK; + pftctl |= CM_GCR_L2_PFT_CONTROL_PFTEN_MSK; + write_gcr_l2_pft_control(pftctl); + + pftctl = read_gcr_l2_pft_control_b(); + pftctl |= CM_GCR_L2_PFT_CONTROL_B_PORTID_MSK; + pftctl |= CM_GCR_L2_PFT_CONTROL_B_CEN_MSK; + write_gcr_l2_pft_control_b(pftctl); + } +} + +static void mips_sc_prefetch_disable(void) +{ + unsigned long pftctl; + + if (mips_cm_revision() < CM_REV_CM2_5) + return; + + pftctl = read_gcr_l2_pft_control(); + pftctl &= ~CM_GCR_L2_PFT_CONTROL_PFTEN_MSK; + write_gcr_l2_pft_control(pftctl); + + pftctl = read_gcr_l2_pft_control_b(); + pftctl &= ~CM_GCR_L2_PFT_CONTROL_B_PORTID_MSK; + pftctl &= ~CM_GCR_L2_PFT_CONTROL_B_CEN_MSK; + write_gcr_l2_pft_control_b(pftctl); +} + +static bool mips_sc_prefetch_is_enabled(void) +{ + unsigned long pftctl; + + if (mips_cm_revision() < CM_REV_CM2_5) + return false; + + pftctl = read_gcr_l2_pft_control(); + if (!(pftctl & CM_GCR_L2_PFT_CONTROL_NPFT_MSK)) + return false; + return !!(pftctl & CM_GCR_L2_PFT_CONTROL_PFTEN_MSK); +} + static struct bcache_ops mips_sc_ops = { .bc_enable = mips_sc_enable, .bc_disable = mips_sc_disable, .bc_wback_inv = mips_sc_wback_inv, - .bc_inv = mips_sc_inv + .bc_inv = mips_sc_inv, + .bc_prefetch_enable = mips_sc_prefetch_enable, + .bc_prefetch_disable = mips_sc_prefetch_disable, + .bc_prefetch_is_enabled = mips_sc_prefetch_is_enabled, }; /* @@ -186,6 +244,7 @@ int mips_sc_init(void) int found = mips_sc_probe(); if (found) { mips_sc_enable(); + mips_sc_prefetch_enable(); bcops = &mips_sc_ops; } return found; -- 2.34.1