[PATCH v2] ARM: cache-l2x0: add resume entry for l2 in secure mode

Barry Song Baohua.Song at csr.com
Sun Sep 25 23:26:09 EDT 2011


we save the l2x0 registers at the first initialization, and platform codes
can get them to restore l2x0 status after wakeup.

Cc: Shawn Guo <shawn.guo at linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
Signed-off-by: Barry Song <Baohua.Song at csr.com>
---
 -v2:
 define the structure l2x0_regs to hold all saved registers;
 make saved copy of registers non-static so that platform codes can access them;
 add asm_offset for l2x0 saved regs(l2x0_regs struct) so that asm codes can use

 arch/arm/include/asm/hardware/cache-l2x0.h |   13 +++++
 arch/arm/include/asm/outercache.h          |    7 +++
 arch/arm/kernel/asm-offsets.c              |    9 +++
 arch/arm/mm/cache-l2x0.c                   |   81 ++++++++++++++++++++++++---
 4 files changed, 101 insertions(+), 9 deletions(-)

diff --git a/arch/arm/include/asm/hardware/cache-l2x0.h b/arch/arm/include/asm/hardware/cache-l2x0.h
index c48cb1e..4f9e81d 100644
--- a/arch/arm/include/asm/hardware/cache-l2x0.h
+++ b/arch/arm/include/asm/hardware/cache-l2x0.h
@@ -96,6 +96,19 @@
 #ifndef __ASSEMBLY__
 extern void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask);
 extern int l2x0_of_init(__u32 aux_val, __u32 aux_mask);
+
+struct l2x0_regs {
+	unsigned long aux_ctrl;
+	/*
+	 * Whether the following registers need to be saved/restored
+	 * depends on platform
+	 */
+	unsigned long tag_latency;
+	unsigned long data_latency;
+	unsigned long filter_start;
+	unsigned long filter_end;
+};
+
 #endif
 
 #endif
diff --git a/arch/arm/include/asm/outercache.h b/arch/arm/include/asm/outercache.h
index d838743..53426c6 100644
--- a/arch/arm/include/asm/outercache.h
+++ b/arch/arm/include/asm/outercache.h
@@ -34,6 +34,7 @@ struct outer_cache_fns {
 	void (*sync)(void);
 #endif
 	void (*set_debug)(unsigned long);
+	void (*resume)(void);
 };
 
 #ifdef CONFIG_OUTER_CACHE
@@ -74,6 +75,12 @@ static inline void outer_disable(void)
 		outer_cache.disable();
 }
 
+static inline void outer_resume(void)
+{
+	if (outer_cache.resume)
+		outer_cache.resume();
+}
+
 #else
 
 static inline void outer_inv_range(phys_addr_t start, phys_addr_t end)
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 16baba2..b8d72a8 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -20,6 +20,7 @@
 #include <asm/thread_info.h>
 #include <asm/memory.h>
 #include <asm/procinfo.h>
+#include <asm/hardware/cache-l2x0.h>
 #include <linux/kbuild.h>
 
 /*
@@ -92,6 +93,14 @@ int main(void)
   DEFINE(S_OLD_R0,		offsetof(struct pt_regs, ARM_ORIG_r0));
   DEFINE(S_FRAME_SIZE,		sizeof(struct pt_regs));
   BLANK();
+#ifdef CONFIG_CACHE_L2X0
+  DEFINE(L2X0_R_AUX_CTRL,	offsetof(struct l2x0_regs, aux_ctrl));
+  DEFINE(L2X0_R_TAG_LATENCY,	offsetof(struct l2x0_regs, tag_latency));
+  DEFINE(L2X0_R_DATA_LATENCY,	offsetof(struct l2x0_regs, data_latency));
+  DEFINE(L2X0_R_FILTER_START,	offsetof(struct l2x0_regs, filter_start));
+  DEFINE(L2X0_R_FILTER_END,	offsetof(struct l2x0_regs, filter_end));
+  BLANK();
+#endif
 #ifdef CONFIG_CPU_HAS_ASID
   DEFINE(MM_CONTEXT_ID,		offsetof(struct mm_struct, context.id));
   BLANK();
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 0d85d22..c22bee1 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -33,6 +33,14 @@ static DEFINE_SPINLOCK(l2x0_lock);
 static uint32_t l2x0_way_mask;	/* Bitmask of active ways */
 static uint32_t l2x0_size;
 
+struct l2x0_regs l2x0_saved_regs;
+
+struct l2x0_of_data {
+	void (*setup)(const struct device_node *,__u32 *, __u32 *);
+	void (*save)(void);
+	void (*resume)(void);
+};
+
 static inline void cache_wait_way(void __iomem *reg, unsigned long mask)
 {
 	/* wait for cache operation by line or way to complete */
@@ -280,7 +288,7 @@ static void l2x0_disable(void)
 	spin_unlock_irqrestore(&l2x0_lock, flags);
 }
 
-static void __init l2x0_unlock(__u32 cache_id)
+static void l2x0_unlock(__u32 cache_id)
 {
 	int lockregs;
 	int i;
@@ -356,6 +364,8 @@ void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
 		/* l2x0 controller is disabled */
 		writel_relaxed(aux, l2x0_base + L2X0_AUX_CTRL);
 
+		l2x0_saved_regs.aux_ctrl = aux;
+
 		l2x0_inv_all();
 
 		/* enable L2X0 */
@@ -445,18 +455,64 @@ static void __init pl310_of_setup(const struct device_node *np,
 	}
 }
 
+static void __init pl310_save(void)
+{
+	l2x0_saved_regs.tag_latency = readl_relaxed(l2x0_base + L2X0_TAG_LATENCY_CTRL);
+	l2x0_saved_regs.data_latency = readl_relaxed(l2x0_base + L2X0_DATA_LATENCY_CTRL);
+	l2x0_saved_regs.filter_end = readl_relaxed(l2x0_base + L2X0_ADDR_FILTER_END);
+	l2x0_saved_regs.filter_start = readl_relaxed(l2x0_base + L2X0_ADDR_FILTER_START);
+}
+
+static void l2x0_resume(void)
+{
+	if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
+		/* restore aux ctrl and enable l2 */
+		l2x0_unlock(readl_relaxed(l2x0_base + L2X0_CACHE_ID));
+
+		writel_relaxed(l2x0_saved_regs.aux_ctrl, l2x0_base + L2X0_AUX_CTRL);
+
+		l2x0_inv_all();
+
+		writel_relaxed(1, l2x0_base + L2X0_CTRL);
+	}
+}
+
+static void pl310_resume(void)
+{
+	if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
+		/* restore pl310 setup */
+		writel_relaxed(l2x0_saved_regs.tag_latency, l2x0_base + L2X0_TAG_LATENCY_CTRL);
+		writel_relaxed(l2x0_saved_regs.data_latency, l2x0_base + L2X0_DATA_LATENCY_CTRL);
+		writel_relaxed(l2x0_saved_regs.filter_end, l2x0_base + L2X0_ADDR_FILTER_END);
+		writel_relaxed(l2x0_saved_regs.filter_start, l2x0_base + L2X0_ADDR_FILTER_START);
+	}
+
+	l2x0_resume();
+}
+
+static const struct l2x0_of_data pl310_data = {
+	pl310_of_setup,
+	pl310_save,
+	pl310_resume,
+};
+
+static const struct l2x0_of_data l2x0_data = {
+	l2x0_of_setup,
+	NULL,
+	l2x0_resume,
+};
+
 static const struct of_device_id l2x0_ids[] __initconst = {
-	{ .compatible = "arm,pl310-cache", .data = pl310_of_setup },
-	{ .compatible = "arm,l220-cache", .data = l2x0_of_setup },
-	{ .compatible = "arm,l210-cache", .data = l2x0_of_setup },
+	{ .compatible = "arm,pl310-cache", .data = (void *)&pl310_data },
+	{ .compatible = "arm,l220-cache", .data = (void *)&l2x0_data },
+	{ .compatible = "arm,l210-cache", .data = (void *)&l2x0_data },
 	{}
 };
 
 int __init l2x0_of_init(__u32 aux_val, __u32 aux_mask)
 {
 	struct device_node *np;
-	void (*l2_setup)(const struct device_node *np,
-		__u32 *aux_val, __u32 *aux_mask);
+	struct l2x0_of_data *data;
 
 	np = of_find_matching_node(NULL, l2x0_ids);
 	if (!np)
@@ -465,13 +521,20 @@ int __init l2x0_of_init(__u32 aux_val, __u32 aux_mask)
 	if (!l2x0_base)
 		return -ENOMEM;
 
+	data = of_match_node(l2x0_ids, np)->data;
+
 	/* L2 configuration can only be changed if the cache is disabled */
 	if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
-		l2_setup = of_match_node(l2x0_ids, np)->data;
-		if (l2_setup)
-			l2_setup(np, &aux_val, &aux_mask);
+		if (data->setup)
+			data->setup(np, &aux_val, &aux_mask);
 	}
+
+	if (data->save)
+		data->save();
+
 	l2x0_init(l2x0_base, aux_val, aux_mask);
+
+	outer_cache.resume = data->resume;
 	return 0;
 }
 #endif
-- 
1.7.1



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