2018-11-08 11:31:43

by Nylon Chen

[permalink] [raw]
Subject: [PATCH v3 2/2] nds32: support hardware prefetcher

We add a config for user to enable or disable this feature.
It can be used to control the hardware prefetch function.

Signed-off-by: Nylon Chen <[email protected]>
---
arch/nds32/Kconfig.cpu | 7 +++++++
arch/nds32/include/asm/bitfield.h | 6 ++++++
arch/nds32/kernel/head.S | 2 +-
arch/nds32/kernel/setup.c | 7 +++++++
4 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/arch/nds32/Kconfig.cpu b/arch/nds32/Kconfig.cpu
index 6482ed877f97..f16edf0582b4 100644
--- a/arch/nds32/Kconfig.cpu
+++ b/arch/nds32/Kconfig.cpu
@@ -177,6 +177,13 @@ config CACHE_L2
Say Y here to enable L2 cache if your SoC are integrated with L2CC.
If unsure, say N.

+config HW_PRE
+ bool "Enable hardware prefetcher"
+ default y
+ help
+ Say Y here to enable hardware prefetcher feature.
+ Only when CPU_VER.REV >= 0x09 can support.
+
menu "Memory configuration"

choice
diff --git a/arch/nds32/include/asm/bitfield.h b/arch/nds32/include/asm/bitfield.h
index c1619730192a..7414fcbbab4e 100644
--- a/arch/nds32/include/asm/bitfield.h
+++ b/arch/nds32/include/asm/bitfield.h
@@ -740,14 +740,20 @@
#define N13MISC_CTL_offRTP 1 /* Disable Return Target Predictor */
#define N13MISC_CTL_offPTEPF 2 /* Disable HPTWK L2 PTE pefetch */
#define N13MISC_CTL_offSP_SHADOW_EN 4 /* Enable shadow stack pointers */
+#define MISC_CTL_offHWPRE 11 /* Enable HardWare PREFETCH */
/* bit 6, 9:31 reserved */

#define N13MISC_CTL_makBTB ( 0x1 << N13MISC_CTL_offBTB )
#define N13MISC_CTL_makRTP ( 0x1 << N13MISC_CTL_offRTP )
#define N13MISC_CTL_makPTEPF ( 0x1 << N13MISC_CTL_offPTEPF )
#define N13MISC_CTL_makSP_SHADOW_EN ( 0x1 << N13MISC_CTL_offSP_SHADOW_EN )
+#define MISC_CTL_makHWPRE_EN ( 0x1 << MISC_CTL_offHWPRE )

+#ifdef CONFIG_HW_PRE
+#define MISC_init (N13MISC_CTL_makBTB|N13MISC_CTL_makRTP|N13MISC_CTL_makSP_SHADOW_EN|MISC_CTL_makHWPRE_EN)
+#else
#define MISC_init (N13MISC_CTL_makBTB|N13MISC_CTL_makRTP|N13MISC_CTL_makSP_SHADOW_EN)
+#endif

/******************************************************************************
* PRUSR_ACC_CTL (Privileged Resource User Access Control Registers)
diff --git a/arch/nds32/kernel/head.S b/arch/nds32/kernel/head.S
index 2c8aac6201be..db64b78b1232 100644
--- a/arch/nds32/kernel/head.S
+++ b/arch/nds32/kernel/head.S
@@ -151,7 +151,7 @@ _tlb:
#endif
mtsr $r3, $TLB_MISC

- mfsr $r0, $MISC_CTL ! Enable BTB and RTP and shadow sp
+ mfsr $r0, $MISC_CTL ! Enable BTB, RTP, shadow sp, and HW_PRE
ori $r0, $r0, #MISC_init
mtsr $r0, $MISC_CTL

diff --git a/arch/nds32/kernel/setup.c b/arch/nds32/kernel/setup.c
index 4b774ca433a9..31d29d92478e 100644
--- a/arch/nds32/kernel/setup.c
+++ b/arch/nds32/kernel/setup.c
@@ -39,6 +39,7 @@
#define HWCAP_FPU_DP 0x040000
#define HWCAP_V2 0x080000
#define HWCAP_DX_REGS 0x100000
+#define HWCAP_HWPRE 0x200000

unsigned long cpu_id, cpu_rev, cpu_cfgid;
bool has_fpu = false;
@@ -75,6 +76,7 @@ static const char *hwcap_str[] = {
"fpu_dp",
"v2",
"dx_regs",
+ "hw_pre",
NULL,
};

@@ -221,6 +223,11 @@ static void __init setup_cpuinfo(void)
if (__nds32__mfsr(NDS32_SR_MSC_CFG) & MSC_CFG_mskL2C)
elf_hwcap |= HWCAP_L2C;

+#ifdef CONFIG_HW_PRE
+ if (__nds32__mfsr(NDS32_SR_MISC_CTL) & MISC_CTL_makHWPRE_EN)
+ elf_hwcap |= HWCAP_HWPRE;
+#endif
+
tmp = __nds32__mfsr(NDS32_SR_CACHE_CTL);
if (!IS_ENABLED(CONFIG_CPU_DCACHE_DISABLE))
tmp |= CACHE_CTL_mskDC_EN;
--
2.18.0