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path: root/drivers/net/can/c_can/c_can_platform.c
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Diffstat (limited to 'drivers/net/can/c_can/c_can_platform.c')
-rw-r--r--drivers/net/can/c_can/c_can_platform.c47
1 files changed, 37 insertions, 10 deletions
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index d66ac265269c..806d92753427 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -37,8 +37,10 @@
#include "c_can.h"
-#define CAN_RAMINIT_START_MASK(i) (1 << (i))
-
+#define CAN_RAMINIT_START_MASK(i) (0x001 << (i))
+#define CAN_RAMINIT_DONE_MASK(i) (0x100 << (i))
+#define CAN_RAMINIT_ALL_MASK(i) (0x101 << (i))
+static DEFINE_SPINLOCK(raminit_lock);
/*
* 16-bit c_can registers can be arranged differently in the memory
* architecture of different implementations. For example: 16-bit
@@ -69,16 +71,41 @@ static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
writew(val, priv->base + 2 * priv->regs[index]);
}
+static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask,
+ u32 val)
+{
+ /* We look only at the bits of our instance. */
+ val &= mask;
+ while ((readl(priv->raminit_ctrlreg) & mask) != val)
+ udelay(1);
+}
+
static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
{
- u32 val;
-
- val = readl(priv->raminit_ctrlreg);
- if (enable)
- val |= CAN_RAMINIT_START_MASK(priv->instance);
- else
- val &= ~CAN_RAMINIT_START_MASK(priv->instance);
- writel(val, priv->raminit_ctrlreg);
+ u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
+ u32 ctrl;
+
+ spin_lock(&raminit_lock);
+
+ ctrl = readl(priv->raminit_ctrlreg);
+ /* We clear the done and start bit first. The start bit is
+ * looking at the 0 -> transition, but is not self clearing;
+ * And we clear the init done bit as well.
+ */
+ ctrl &= ~CAN_RAMINIT_START_MASK(priv->instance);
+ ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+ writel(ctrl, priv->raminit_ctrlreg);
+ ctrl &= ~CAN_RAMINIT_DONE_MASK(priv->instance);
+ c_can_hw_raminit_wait(priv, ctrl, mask);
+
+ if (enable) {
+ /* Set start bit and wait for the done bit. */
+ ctrl |= CAN_RAMINIT_START_MASK(priv->instance);
+ writel(ctrl, priv->raminit_ctrlreg);
+ ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+ c_can_hw_raminit_wait(priv, ctrl, mask);
+ }
+ spin_unlock(&raminit_lock);
}
static struct platform_device_id c_can_id_table[] = {