[PATCH v2 09/12] hwrng: bcm2835-rng: Add Broadcom MIPS I/O accessors

From: Florian Fainelli
Date: Tue Nov 07 2017 - 19:47:19 EST


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@xxxxxxxxx>
---
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 3a607472687d..6dd8f48701b5 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