[U-Boot] [PATCH v2] arc: significant cache rework
Alexey Brodkin
Alexey.Brodkin at synopsys.com
Wed Jul 1 16:15:31 CEST 2015
From: Alexey Brodkin <Alexey.Brodkin at synopsys.com>
[1] Align cache management functions to those in Linux kernel. I.e.:
a) Use the same functions for all cache ops (D$ Inv/Flush)
b) Split cache ops in 3 sub-functions: "before", "lineloop" and
"after". That way we may re-use "before" and "after" functions for
region and full cache ops.
[2] Implement full-functional L2 (SLC) management. Before SLC was
simply disabled early on boot. If SLC exists corresponding ops are run on cache
flush/invalidate.
[3] Disable/enable corresponding caches early on boot. So if U-Boot is
configured to use caches they will be used at all times (this is useful
in particular for speed-up of relocation).
Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
---
Compared to v1:
* Remove explicit selection of L2CACHE on/off in Kconfig, check this in runtime
and use L2 ops only when L2 is detected.
This allows run the same executable on HW with and without L2 cache.
---
arch/arc/include/asm/arcregs.h | 5 +-
arch/arc/include/asm/cache.h | 7 +-
arch/arc/lib/cache.c | 375 ++++++++++++++++++++++++++++-------------
arch/arc/lib/cpu.c | 2 +
arch/arc/lib/init_helpers.c | 10 +-
arch/arc/lib/start.S | 46 ++++-
6 files changed, 300 insertions(+), 145 deletions(-)
diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h
index 0e11dcc..667f218 100644
--- a/arch/arc/include/asm/arcregs.h
+++ b/arch/arc/include/asm/arcregs.h
@@ -47,9 +47,12 @@
#endif
#define ARC_BCR_DC_BUILD 0x72
#define ARC_BCR_SLC 0xce
-#define ARC_AUX_SLC_CONTROL 0x903
+#define ARC_AUX_SLC_CONFIG 0x901
+#define ARC_AUX_SLC_CTRL 0x903
#define ARC_AUX_SLC_FLUSH 0x904
#define ARC_AUX_SLC_INVALIDATE 0x905
+#define ARC_AUX_SLC_IVDL 0x910
+#define ARC_AUX_SLC_FLDL 0x912
#ifndef __ASSEMBLY__
/* Accessors for auxiliary registers */
diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h
index 0b3ebd9..432606a 100644
--- a/arch/arc/include/asm/cache.h
+++ b/arch/arc/include/asm/cache.h
@@ -29,12 +29,7 @@
#ifndef __ASSEMBLY__
-#ifdef CONFIG_ISA_ARCV2
-void slc_enable(void);
-void slc_disable(void);
-void slc_flush(void);
-void slc_invalidate(void);
-#endif
+void cache_init(void);
#endif /* __ASSEMBLY__ */
diff --git a/arch/arc/lib/cache.c b/arch/arc/lib/cache.c
index e369e5a..ed8e8e7 100644
--- a/arch/arc/lib/cache.c
+++ b/arch/arc/lib/cache.c
@@ -5,9 +5,13 @@
*/
#include <config.h>
+#include <linux/compiler.h>
+#include <linux/kernel.h>
#include <asm/arcregs.h>
#include <asm/cache.h>
+#define CACHE_LINE_MASK (~(CONFIG_SYS_CACHELINE_SIZE - 1))
+
/* Bit values in IC_CTRL */
#define IC_CTRL_CACHE_DISABLE (1 << 0)
@@ -18,60 +22,186 @@
#define CACHE_VER_NUM_MASK 0xF
#define SLC_CTRL_SB (1 << 2)
+#define OP_INV 0x1
+#define OP_FLUSH 0x2
+#define OP_INV_IC 0x3
+
+#ifdef CONFIG_ISA_ARCV2
+/*
+ * By default that variable will fall into .bss section.
+ * But .bss section is not relocated and so it will be initilized before
+ * relocation but will be used after being zeroed.
+ */
+int slc_line_sz __section(".data");
+int slc_exists __section(".data");
+
+static unsigned int __before_slc_op(const int op)
+{
+ unsigned int reg = reg;
+
+ if (op == OP_INV) {
+ /*
+ * IM is set by default and implies Flush-n-inv
+ * Clear it here for vanilla inv
+ */
+ reg = read_aux_reg(ARC_AUX_SLC_CTRL);
+ write_aux_reg(ARC_AUX_SLC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
+ }
+
+ return reg;
+}
+
+static void __after_slc_op(const int op, unsigned int reg)
+{
+ if (op & OP_FLUSH) /* flush / flush-n-inv both wait */
+ while (read_aux_reg(ARC_AUX_SLC_CTRL) &
+ DC_CTRL_FLUSH_STATUS)
+ ;
+
+ /* Switch back to default Invalidate mode */
+ if (op == OP_INV)
+ write_aux_reg(ARC_AUX_SLC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
+}
+
+static inline void __slc_line_loop(unsigned long paddr, unsigned long sz,
+ const int op)
+{
+ unsigned int aux_cmd;
+ int num_lines;
+
+#define SLC_LINE_MASK (~(slc_line_sz - 1))
+
+ aux_cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
+
+ sz += paddr & ~SLC_LINE_MASK;
+ paddr &= SLC_LINE_MASK;
+
+ num_lines = DIV_ROUND_UP(sz, slc_line_sz);
+
+ while (num_lines-- > 0) {
+ write_aux_reg(aux_cmd, paddr);
+ paddr += slc_line_sz;
+ }
+}
+
+static inline void __slc_entire_op(const int cacheop)
+{
+ int aux;
+ unsigned int ctrl_reg = __before_slc_op(cacheop);
+
+ if (cacheop & OP_INV) /* Inv or flush-n-inv use same cmd reg */
+ aux = ARC_AUX_SLC_INVALIDATE;
+ else
+ aux = ARC_AUX_SLC_FLUSH;
+
+ write_aux_reg(aux, 0x1);
+
+ __after_slc_op(cacheop, ctrl_reg);
+}
+
+static inline void __slc_line_op(unsigned long paddr, unsigned long sz,
+ const int cacheop)
+{
+ unsigned int ctrl_reg = __before_slc_op(cacheop);
+ __slc_line_loop(paddr, sz, cacheop);
+ __after_slc_op(cacheop, ctrl_reg);
+}
+#else
+#define __slc_entire_op(cacheop)
+#define __slc_line_op(paddr, sz, cacheop)
+#endif
+
+static inline int icache_exists(void)
+{
+ /* Check if Instruction Cache is available */
+ if (read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK)
+ return 1;
+ else
+ return 0;
+}
+
+static inline int dcache_exists(void)
+{
+ /* Check if Data Cache is available */
+ if (read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK)
+ return 1;
+ else
+ return 0;
+}
+
+void cache_init(void)
+{
+#ifdef CONFIG_ISA_ARCV2
+ /* Check if System-Level Cache (SLC) is available */
+ if (read_aux_reg(ARC_BCR_SLC) & CACHE_VER_NUM_MASK) {
+#define LSIZE_OFFSET 4
+#define LSIZE_MASK 3
+ if (read_aux_reg(ARC_AUX_SLC_CONFIG) &
+ (LSIZE_MASK << LSIZE_OFFSET))
+ slc_line_sz = 64;
+ else
+ slc_line_sz = 128;
+ slc_exists = 1;
+ } else {
+ slc_exists = 0;
+ }
+#endif
+}
+
int icache_status(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK))
+ if (!icache_exists())
return 0;
- return (read_aux_reg(ARC_AUX_IC_CTRL) & IC_CTRL_CACHE_DISABLE) !=
- IC_CTRL_CACHE_DISABLE;
+ if (read_aux_reg(ARC_AUX_IC_CTRL) & IC_CTRL_CACHE_DISABLE)
+ return 0;
+ else
+ return 1;
}
void icache_enable(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK))
- return;
-
- write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) &
- ~IC_CTRL_CACHE_DISABLE);
+ if (icache_exists())
+ write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) &
+ ~IC_CTRL_CACHE_DISABLE);
}
void icache_disable(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK))
- return;
-
- write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) |
- IC_CTRL_CACHE_DISABLE);
+ if (icache_exists())
+ write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) |
+ IC_CTRL_CACHE_DISABLE);
}
+#ifndef CONFIG_SYS_DCACHE_OFF
void invalidate_icache_all(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK))
- return;
-
/* Any write to IC_IVIC register triggers invalidation of entire I$ */
- write_aux_reg(ARC_AUX_IC_IVIC, 1);
+ if (icache_status()) {
+ write_aux_reg(ARC_AUX_IC_IVIC, 1);
+ read_aux_reg(ARC_AUX_IC_CTRL); /* blocks */
+ }
}
+#else
+void invalidate_icache_all(void)
+{
+}
+#endif
int dcache_status(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK))
+ if (!dcache_exists())
return 0;
- return (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_CACHE_DISABLE) !=
- DC_CTRL_CACHE_DISABLE;
+ if (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_CACHE_DISABLE)
+ return 0;
+ else
+ return 1;
}
void dcache_enable(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK))
+ if (!dcache_exists())
return;
write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) &
@@ -80,139 +210,144 @@ void dcache_enable(void)
void dcache_disable(void)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK))
+ if (!dcache_exists())
return;
write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) |
DC_CTRL_CACHE_DISABLE);
}
-void flush_dcache_all(void)
-{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK))
- return;
-
- /* Do flush of entire cache */
- write_aux_reg(ARC_AUX_DC_FLSH, 1);
-
- /* Wait flush end */
- while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
- ;
-}
-
#ifndef CONFIG_SYS_DCACHE_OFF
-static void dcache_flush_line(unsigned addr)
+/*
+ * Common Helper for Line Operations on {I,D}-Cache
+ */
+static inline void __cache_line_loop(unsigned long paddr, unsigned long sz,
+ const int cacheop)
{
+ unsigned int aux_cmd;
#if (CONFIG_ARC_MMU_VER == 3)
- write_aux_reg(ARC_AUX_DC_PTAG, addr);
+ unsigned int aux_tag;
#endif
- write_aux_reg(ARC_AUX_DC_FLDL, addr);
+ int num_lines;
- /* Wait flush end */
- while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
- ;
-
-#ifndef CONFIG_SYS_ICACHE_OFF
- /*
- * Invalidate I$ for addresses range just flushed from D$.
- * If we try to execute data flushed above it will be valid/correct
- */
+ if (cacheop == OP_INV_IC) {
+ aux_cmd = ARC_AUX_IC_IVIL;
#if (CONFIG_ARC_MMU_VER == 3)
- write_aux_reg(ARC_AUX_IC_PTAG, addr);
+ aux_tag = ARC_AUX_IC_PTAG;
#endif
- write_aux_reg(ARC_AUX_IC_IVIL, addr);
-#endif /* CONFIG_SYS_ICACHE_OFF */
-}
-#endif /* CONFIG_SYS_DCACHE_OFF */
-
-void flush_dcache_range(unsigned long start, unsigned long end)
-{
-#ifndef CONFIG_SYS_DCACHE_OFF
- unsigned int addr;
+ } else {
+ /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
+ aux_cmd = cacheop & OP_INV ? ARC_AUX_DC_IVDL : ARC_AUX_DC_FLDL;
+#if (CONFIG_ARC_MMU_VER == 3)
+ aux_tag = ARC_AUX_DC_PTAG;
+#endif
+ }
- start = start & (~(CONFIG_SYS_CACHELINE_SIZE - 1));
- end = end & (~(CONFIG_SYS_CACHELINE_SIZE - 1));
+ sz += paddr & ~CACHE_LINE_MASK;
+ paddr &= CACHE_LINE_MASK;
- for (addr = start; addr <= end; addr += CONFIG_SYS_CACHELINE_SIZE)
- dcache_flush_line(addr);
-#endif /* CONFIG_SYS_DCACHE_OFF */
-}
+ num_lines = DIV_ROUND_UP(sz, CONFIG_SYS_CACHELINE_SIZE);
-void invalidate_dcache_range(unsigned long start, unsigned long end)
-{
-#ifndef CONFIG_SYS_DCACHE_OFF
- unsigned int addr;
-
- start = start & (~(CONFIG_SYS_CACHELINE_SIZE - 1));
- end = end & (~(CONFIG_SYS_CACHELINE_SIZE - 1));
-
- for (addr = start; addr <= end; addr += CONFIG_SYS_CACHELINE_SIZE) {
+ while (num_lines-- > 0) {
#if (CONFIG_ARC_MMU_VER == 3)
- write_aux_reg(ARC_AUX_DC_PTAG, addr);
+ write_aux_reg(aux_tag, paddr);
#endif
- write_aux_reg(ARC_AUX_DC_IVDL, addr);
+ write_aux_reg(aux_cmd, paddr);
+ paddr += CONFIG_SYS_CACHELINE_SIZE;
}
-#endif /* CONFIG_SYS_DCACHE_OFF */
}
-void invalidate_dcache_all(void)
+static unsigned int __before_dc_op(const int op)
{
- /* If no cache in CPU exit immediately */
- if (!(read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK))
- return;
+ unsigned int reg;
+
+ if (op == OP_INV) {
+ /*
+ * IM is set by default and implies Flush-n-inv
+ * Clear it here for vanilla inv
+ */
+ reg = read_aux_reg(ARC_AUX_DC_CTRL);
+ write_aux_reg(ARC_AUX_DC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
+ }
- /* Write 1 to DC_IVDC register triggers invalidation of entire D$ */
- write_aux_reg(ARC_AUX_DC_IVDC, 1);
+ return reg;
}
-void flush_cache(unsigned long start, unsigned long size)
+static void __after_dc_op(const int op, unsigned int reg)
{
- flush_dcache_range(start, start + size);
+ if (op & OP_FLUSH) /* flush / flush-n-inv both wait */
+ while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
+ ;
+
+ /* Switch back to default Invalidate mode */
+ if (op == OP_INV)
+ write_aux_reg(ARC_AUX_DC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
}
-#ifdef CONFIG_ISA_ARCV2
-void slc_enable(void)
+static inline void __dc_entire_op(const int cacheop)
{
- /* If SLC ver = 0, no SLC present in CPU */
- if (!(read_aux_reg(ARC_BCR_SLC) & 0xff))
- return;
+ int aux;
+ unsigned int ctrl_reg = __before_dc_op(cacheop);
- write_aux_reg(ARC_AUX_SLC_CONTROL,
- read_aux_reg(ARC_AUX_SLC_CONTROL) & ~1);
-}
+ if (cacheop & OP_INV) /* Inv or flush-n-inv use same cmd reg */
+ aux = ARC_AUX_DC_IVDC;
+ else
+ aux = ARC_AUX_DC_FLSH;
-void slc_disable(void)
-{
- /* If SLC ver = 0, no SLC present in CPU */
- if (!(read_aux_reg(ARC_BCR_SLC) & 0xff))
- return;
+ write_aux_reg(aux, 0x1);
- write_aux_reg(ARC_AUX_SLC_CONTROL,
- read_aux_reg(ARC_AUX_SLC_CONTROL) | 1);
+ __after_dc_op(cacheop, ctrl_reg);
}
-void slc_flush(void)
+static inline void __dc_line_op(unsigned long paddr, unsigned long sz,
+ const int cacheop)
{
- /* If SLC ver = 0, no SLC present in CPU */
- if (!(read_aux_reg(ARC_BCR_SLC) & 0xff))
- return;
+ unsigned int ctrl_reg = __before_dc_op(cacheop);
+ __cache_line_loop(paddr, sz, cacheop);
+ __after_dc_op(cacheop, ctrl_reg);
+}
+#else
+#define __dc_entire_op(cacheop)
+#define __dc_line_op(paddr, sz, cacheop)
+#endif /* !CONFIG_SYS_DCACHE_OFF */
- write_aux_reg(ARC_AUX_SLC_FLUSH, 1);
+void invalidate_dcache_range(unsigned long start, unsigned long end)
+{
+ __dc_line_op(start, end - start, OP_INV);
+#ifdef CONFIG_ISA_ARCV2
+ if (slc_exists)
+ __slc_line_op(start, end - start, OP_INV);
+#endif
+}
- /* Wait flush end */
- while (read_aux_reg(ARC_AUX_SLC_CONTROL) & SLC_CTRL_SB)
- ;
+void flush_dcache_range(unsigned long start, unsigned long end)
+{
+ __dc_line_op(start, end - start, OP_FLUSH);
+#ifdef CONFIG_ISA_ARCV2
+ if (slc_exists)
+ __slc_line_op(start, end - start, OP_FLUSH);
+#endif
}
-void slc_invalidate(void)
+void flush_cache(unsigned long start, unsigned long size)
{
- /* If SLC ver = 0, no SLC present in CPU */
- if (!(read_aux_reg(ARC_BCR_SLC) & 0xff))
- return;
+ flush_dcache_range(start, start + size);
+}
- write_aux_reg(ARC_AUX_SLC_INVALIDATE, 1);
+void invalidate_dcache_all(void)
+{
+ __dc_entire_op(OP_INV);
+#ifdef CONFIG_ISA_ARCV2
+ if (slc_exists)
+ __slc_entire_op(OP_INV);
+#endif
}
-#endif /* CONFIG_ISA_ARCV2 */
+void flush_dcache_all(void)
+{
+ __dc_entire_op(OP_FLUSH);
+#ifdef CONFIG_ISA_ARCV2
+ if (slc_exists)
+ __slc_entire_op(OP_FLUSH);
+#endif
+}
diff --git a/arch/arc/lib/cpu.c b/arch/arc/lib/cpu.c
index 3c930bc..4e4dd74 100644
--- a/arch/arc/lib/cpu.c
+++ b/arch/arc/lib/cpu.c
@@ -23,6 +23,8 @@ int arch_cpu_init(void)
gd->cpu_clk = CONFIG_SYS_CLK_FREQ;
gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
+ cache_init();
+
return 0;
}
diff --git a/arch/arc/lib/init_helpers.c b/arch/arc/lib/init_helpers.c
index 25690ee..dbc8d68 100644
--- a/arch/arc/lib/init_helpers.c
+++ b/arch/arc/lib/init_helpers.c
@@ -10,16 +10,8 @@ DECLARE_GLOBAL_DATA_PTR;
int init_cache_f_r(void)
{
-#ifndef CONFIG_SYS_ICACHE_OFF
- icache_enable();
- /* Make sure no stale entries persist from before we disabled cache */
- invalidate_icache_all();
-#endif
-
#ifndef CONFIG_SYS_DCACHE_OFF
- dcache_enable();
- /* Make sure no stale entries persist from before we disabled cache */
- invalidate_dcache_all();
+ flush_dcache_all();
#endif
return 0;
}
diff --git a/arch/arc/lib/start.S b/arch/arc/lib/start.S
index e1ef19c..26a5934 100644
--- a/arch/arc/lib/start.S
+++ b/arch/arc/lib/start.S
@@ -13,18 +13,46 @@ ENTRY(_start)
/* Setup interrupt vector base that matches "__text_start" */
sr __ivt_start, [ARC_AUX_INTR_VEC_BASE]
- /* Setup stack- and frame-pointers */
- mov %sp, CONFIG_SYS_INIT_SP_ADDR
- mov %fp, %sp
+ ; Disable/enable I-cache according to configuration
+ lr r5, [ARC_BCR_IC_BUILD]
+ breq r5, 0, 1f ; I$ doesn't exist
+ lr r5, [ARC_AUX_IC_CTRL]
+#ifndef CONFIG_SYS_ICACHE_OFF
+ bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
+#else
+ bset r5, r5, 0 ; I$ exists, but is not used
+#endif
+ sr r5, [ARC_AUX_IC_CTRL]
+
+1:
+ ; Disable/enable D-cache according to configuration
+ lr r5, [ARC_BCR_DC_BUILD]
+ breq r5, 0, 1f ; D$ doesn't exist
+ lr r5, [ARC_AUX_DC_CTRL]
+ bclr r5, r5, 6 ; Invalidate (discard w/o wback)
+#ifndef CONFIG_SYS_DCACHE_OFF
+ bclr r5, r5, 0 ; Enable (+Inv)
+#else
+ bset r5, r5, 0 ; Disable (+Inv)
+#endif
+ sr r5, [ARC_AUX_DC_CTRL]
- /* Unconditionally disable caches */
+1:
#ifdef CONFIG_ISA_ARCV2
- bl slc_flush
- bl slc_disable
+ ; Disable System-Level Cache (SLC)
+ lr r5, [ARC_BCR_SLC]
+ breq r5, 0, 1f ; SLC doesn't exist
+ lr r5, [ARC_AUX_SLC_CTRL]
+ bclr r5, r5, 6 ; Invalidate (discard w/o wback)
+ bclr r5, r5, 0 ; Enable (+Inv)
+ sr r5, [ARC_AUX_SLC_CTRL]
+
+1:
#endif
- bl flush_dcache_all
- bl dcache_disable
- bl icache_disable
+
+ /* Setup stack- and frame-pointers */
+ mov %sp, CONFIG_SYS_INIT_SP_ADDR
+ mov %fp, %sp
/* Allocate and zero GD, update SP */
mov %r0, %sp
--
2.4.3
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