[PATCH] ARM: tegra: only run PL310 init on systems with one

Stephen Warren
2014-02-18T23:51:58Z

From: Stephen Warren <swarren@nvidia.com>

Fix tegra_init_cache() to check whether the system has a PL310 cache
before touching the PL310 registers. This prevents access to non-existent
registers on Tegra114 and later.

Note for stable kernels:
In <= v3.12, the file to patch is arch/arm/mach-tegra/common.c.

Cc: <stable@vger.kernel.org> # v3.9+
Signed-off-by: Stephen Warren <swarren@nvidia.com>
---
Another fix for 3.14

arch/arm/mach-tegra/tegra.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/arch/arm/mach-tegra/tegra.c b/arch/arm/mach-tegra/tegra.c
index 303a285d80fd..6191603379e1 100644
--- a/arch/arm/mach-tegra/tegra.c
+++ b/arch/arm/mach-tegra/tegra.c
@@ -73,10 +73,20 @@ u32 tegra_uart_config[3] = {
static void __init tegra_init_cache(void)
{
#ifdef CONFIG_CACHE_L2X0
+ static const struct of_device_id pl310_ids[] __initconst = {
+ { .compatible = "arm,pl310-cache", },
+ {}
+ };
+
+ struct device_node *np;
int ret;
void __iomem *p = IO_ADDRESS(TEGRA_ARM_PERIF_BASE) + 0x3000;
u32 aux_ctrl, cache_type;

+ np = of_find_matching_node(NULL, pl310_ids);
+ if (!np)
+ return;
+
cache_type = readl(p + L2X0_CACHE_TYPE);
aux_ctrl = (cache_type & 0x700) << (17-8);
aux_ctrl |= 0x7C400001;
--
1.8.1.5