[PATCH 09/12] hwrng: bcm2835-rng: Add Broadcom MIPS I/O accessors

Florian Fainelli f.fainelli at gmail.com
Wed Nov 1 18:04:05 PDT 2017


Broadcom MIPS HW is always strapped to match the system-wide endian such
that all I/O access to this RNG block is done with the native CPU
endian, account for that.

Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
---
 drivers/char/hw_random/bcm2835-rng.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 500275d55044..650e0033c273 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -44,13 +44,22 @@ static inline struct bcm2835_rng_priv *to_rng_priv(struct hwrng *rng)
 
 static inline u32 rng_readl(struct bcm2835_rng_priv *priv, u32 offset)
 {
-	return readl(priv->base + offset);
+	/* MIPS chips strapped for BE will automagically configure the
+	 * peripheral registers for CPU-native byte order.
+	 */
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		return __raw_readl(priv->base + offset);
+	else
+		return readl(priv->base + offset);
 }
 
 static inline void rng_writel(struct bcm2835_rng_priv *priv, u32 val,
 			      u32 offset)
 {
-	writel(val, priv->base + offset);
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		__raw_writel(val, priv->base + offset);
+	else
+		writel(val, priv->base + offset);
 }
 
 static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max,
-- 
2.9.3




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