[ 11/12] ARM: 7080/1: l2x0: make sure I&D are not locked down on init

From: Greg Kroah-Hartman
Date: Sun Aug 18 2013 - 16:29:43 EST


3.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: Linus Walleij <linus.walleij@xxxxxxxxxx>

commit bac7e6ecf60933b68af910eb4c83a775a8b20b19 upstream.

Fighting unfixed U-Boots and other beasts that may the cache in
a locked-down state when starting the kernel, we make sure to
disable all cache lock-down when initializing the l2x0 so we
are in a known state.

Reviewed-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Reported-by: Jan Rinze <janrinze@xxxxxxxxx>
Cc: Srinidhi Kasagar <srinidhi.kasagar@xxxxxxxxxxxxxx>
Cc: Rabin Vincent <rabin.vincent@xxxxxxxxxxxxxx>
Cc: Adrian Bunk <adrian.bunk@xxxxxxxxxx>
Cc: Rob Herring <robherring2@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Tested-by: Robert Marklund <robert.marklund@xxxxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm/include/asm/hardware/cache-l2x0.h | 9 +++++++--
arch/arm/mm/cache-l2x0.c | 21 +++++++++++++++++++++
2 files changed, 28 insertions(+), 2 deletions(-)

--- a/arch/arm/include/asm/hardware/cache-l2x0.h
+++ b/arch/arm/include/asm/hardware/cache-l2x0.h
@@ -45,8 +45,13 @@
#define L2X0_CLEAN_INV_LINE_PA 0x7F0
#define L2X0_CLEAN_INV_LINE_IDX 0x7F8
#define L2X0_CLEAN_INV_WAY 0x7FC
-#define L2X0_LOCKDOWN_WAY_D 0x900
-#define L2X0_LOCKDOWN_WAY_I 0x904
+/*
+ * The lockdown registers repeat 8 times for L310, the L210 has only one
+ * D and one I lockdown register at 0x0900 and 0x0904.
+ */
+#define L2X0_LOCKDOWN_WAY_D_BASE 0x900
+#define L2X0_LOCKDOWN_WAY_I_BASE 0x904
+#define L2X0_LOCKDOWN_STRIDE 0x08
#define L2X0_TEST_OPERATION 0xF00
#define L2X0_LINE_DATA 0xF10
#define L2X0_LINE_TAG 0xF30
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -277,6 +277,25 @@ static void l2x0_disable(void)
spin_unlock_irqrestore(&l2x0_lock, flags);
}

+static void __init l2x0_unlock(__u32 cache_id)
+{
+ int lockregs;
+ int i;
+
+ if (cache_id == L2X0_CACHE_ID_PART_L310)
+ lockregs = 8;
+ else
+ /* L210 and unknown types */
+ lockregs = 1;
+
+ for (i = 0; i < lockregs; i++) {
+ writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_D_BASE +
+ i * L2X0_LOCKDOWN_STRIDE);
+ writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_I_BASE +
+ i * L2X0_LOCKDOWN_STRIDE);
+ }
+}
+
void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
{
__u32 aux;
@@ -328,6 +347,8 @@ void __init l2x0_init(void __iomem *base
* accessing the below registers will fault.
*/
if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
+ /* Make sure that I&D is not locked down when starting */
+ l2x0_unlock(cache_id);

/* l2x0 controller is disabled */
writel_relaxed(aux, l2x0_base + L2X0_AUX_CTRL);


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