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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.c128
1 files changed, 111 insertions, 17 deletions
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index 294ced3cc22..12430be6448 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -37,48 +37,126 @@
#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))
+#define DCAN_RAM_INIT_BIT (1 << 3)
+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
* registers can be aligned to a 16-bit boundary or 32-bit boundary etc.
* Handle the same by providing a common read/write interface.
*/
-static u16 c_can_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv,
+static u16 c_can_plat_read_reg_aligned_to_16bit(const struct c_can_priv *priv,
enum reg index)
{
return readw(priv->base + priv->regs[index]);
}
-static void c_can_plat_write_reg_aligned_to_16bit(struct c_can_priv *priv,
+static void c_can_plat_write_reg_aligned_to_16bit(const struct c_can_priv *priv,
enum reg index, u16 val)
{
writew(val, priv->base + priv->regs[index]);
}
-static u16 c_can_plat_read_reg_aligned_to_32bit(struct c_can_priv *priv,
+static u16 c_can_plat_read_reg_aligned_to_32bit(const struct c_can_priv *priv,
enum reg index)
{
return readw(priv->base + 2 * priv->regs[index]);
}
-static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
+static void c_can_plat_write_reg_aligned_to_32bit(const struct c_can_priv *priv,
enum reg index, u16 val)
{
writew(val, priv->base + 2 * priv->regs[index]);
}
-static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+static void c_can_hw_raminit_wait_ti(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_ti(const struct c_can_priv *priv, bool enable)
+{
+ 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_ti(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_ti(priv, ctrl, mask);
+ }
+ spin_unlock(&raminit_lock);
+}
+
+static u32 c_can_plat_read_reg32(const struct c_can_priv *priv, enum reg index)
{
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);
+ val = priv->read_reg(priv, index);
+ val |= ((u32) priv->read_reg(priv, index + 1)) << 16;
+
+ return val;
+}
+
+static void c_can_plat_write_reg32(const struct c_can_priv *priv, enum reg index,
+ u32 val)
+{
+ priv->write_reg(priv, index + 1, val >> 16);
+ priv->write_reg(priv, index, val);
+}
+
+static u32 d_can_plat_read_reg32(const struct c_can_priv *priv, enum reg index)
+{
+ return readl(priv->base + priv->regs[index]);
+}
+
+static void d_can_plat_write_reg32(const struct c_can_priv *priv, enum reg index,
+ u32 val)
+{
+ writel(val, priv->base + priv->regs[index]);
+}
+
+static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask)
+{
+ while (priv->read_reg32(priv, C_CAN_FUNCTION_REG) & mask)
+ udelay(1);
+}
+
+static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+{
+ u32 ctrl;
+
+ ctrl = priv->read_reg32(priv, C_CAN_FUNCTION_REG);
+ ctrl &= ~DCAN_RAM_INIT_BIT;
+ priv->write_reg32(priv, C_CAN_FUNCTION_REG, ctrl);
+ c_can_hw_raminit_wait(priv, ctrl);
+
+ if (enable) {
+ ctrl |= DCAN_RAM_INIT_BIT;
+ priv->write_reg32(priv, C_CAN_FUNCTION_REG, ctrl);
+ c_can_hw_raminit_wait(priv, ctrl);
+ }
}
static struct platform_device_id c_can_id_table[] = {
@@ -174,11 +252,15 @@ static int c_can_plat_probe(struct platform_device *pdev)
case IORESOURCE_MEM_32BIT:
priv->read_reg = c_can_plat_read_reg_aligned_to_32bit;
priv->write_reg = c_can_plat_write_reg_aligned_to_32bit;
+ priv->read_reg32 = c_can_plat_read_reg32;
+ priv->write_reg32 = c_can_plat_write_reg32;
break;
case IORESOURCE_MEM_16BIT:
default:
priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+ priv->read_reg32 = c_can_plat_read_reg32;
+ priv->write_reg32 = c_can_plat_write_reg32;
break;
}
break;
@@ -187,6 +269,8 @@ static int c_can_plat_probe(struct platform_device *pdev)
priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+ priv->read_reg32 = d_can_plat_read_reg32;
+ priv->write_reg32 = d_can_plat_write_reg32;
if (pdev->dev.of_node)
priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
@@ -194,11 +278,21 @@ static int c_can_plat_probe(struct platform_device *pdev)
priv->instance = pdev->id;
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- priv->raminit_ctrlreg = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(priv->raminit_ctrlreg) || (int)priv->instance < 0)
+ /* Not all D_CAN modules have a separate register for the D_CAN
+ * RAM initialization. Use default RAM init bit in D_CAN module
+ * if not specified in DT.
+ */
+ if (!res) {
+ priv->raminit = c_can_hw_raminit;
+ break;
+ }
+
+ priv->raminit_ctrlreg = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (IS_ERR(priv->raminit_ctrlreg) || priv->instance < 0)
dev_info(&pdev->dev, "control memory is not used for raminit\n");
else
- priv->raminit = c_can_hw_raminit;
+ priv->raminit = c_can_hw_raminit_ti;
break;
default:
ret = -EINVAL;
@@ -322,7 +416,7 @@ static struct platform_driver c_can_plat_driver = {
.driver = {
.name = KBUILD_MODNAME,
.owner = THIS_MODULE,
- .of_match_table = of_match_ptr(c_can_of_table),
+ .of_match_table = c_can_of_table,
},
.probe = c_can_plat_probe,
.remove = c_can_plat_remove,