@@ -12,6 +12,9 @@ Required properties:
Optional properties:
- ti,hwmods : Must be "d_can<n>" or "c_can<n>", n being the
instance number
+- syscon-raminit : Handle to system control region that contains the
+ RAMINIT register, register offset to the RAMINIT
+ register and the CAN instance number (0 offset).
Note: "ti,hwmods" field is used to fetch the base address and irq
resources from TI, omap hwmod data base during device registration.
@@ -183,6 +183,13 @@ struct c_can_driver_data {
bool raminit_pulse; /* If set, sets and clears START bit (pulse) */
};
+/* Out of band RAMINIT register access via syscon regmap */
+struct c_can_raminit {
+ struct regmap *syscon; /* for raminit ctrl. reg. access */
+ unsigned int reg; /* register index within syscon */
+ struct raminit_bits bits;
+};
+
/* c_can private data structure */
struct c_can_priv {
struct can_priv can; /* must be the first member */
@@ -200,8 +207,7 @@ struct c_can_priv {
const u16 *regs;
void *priv; /* for board-specific data */
enum c_can_dev_id type;
- u32 __iomem *raminit_ctrlreg;
- int instance;
+ struct c_can_raminit raminit_sys; /* RAMINIT via syscon regmap */
void (*raminit) (const struct c_can_priv *priv, bool enable);
u32 comm_rcv_high;
u32 rxmasked;
@@ -32,14 +32,13 @@
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
#include <linux/can/dev.h>
#include "c_can.h"
-#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);
/*
@@ -72,48 +71,57 @@ static void c_can_plat_write_reg_aligned_to_32bit(const struct c_can_priv *priv,
writew(val, priv->base + 2 * priv->regs[index]);
}
-static void c_can_hw_raminit_wait_ti(const struct c_can_priv *priv, u32 mask,
- u32 val)
+static void c_can_hw_raminit_wait_syscon(const struct c_can_priv *priv,
+ u32 mask, u32 val)
{
+ const struct c_can_raminit *raminit = &priv->raminit_sys;
int timeout = 0;
+ u32 ctrl = 0;
/* We look only at the bits of our instance. */
val &= mask;
- while ((readl(priv->raminit_ctrlreg) & mask) != val) {
+ do {
udelay(1);
timeout++;
+ regmap_read(raminit->syscon, raminit->reg, &ctrl);
if (timeout == 1000) {
dev_err(&priv->dev->dev, "%s: time out\n", __func__);
break;
}
- }
+ } while ((ctrl & mask) != val);
}
-static void c_can_hw_raminit_ti(const struct c_can_priv *priv, bool enable)
+static void c_can_hw_raminit_syscon(const struct c_can_priv *priv, bool enable)
{
- u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
- u32 ctrl;
+ const struct c_can_raminit *raminit = &priv->raminit_sys;
+ u32 ctrl = 0;
+ u32 mask;
spin_lock(&raminit_lock);
- ctrl = readl(priv->raminit_ctrlreg);
+ mask = 1 << raminit->bits.start | 1 << raminit->bits.done;
+ regmap_read(raminit->syscon, raminit->reg, &ctrl);
+
/* 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.
+ * NOTE: DONE must be written with 1 to clear it.
*/
- 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, mask, ctrl);
+ ctrl &= ~(1 << raminit->bits.start);
+ ctrl |= 1 << raminit->bits.done;
+ regmap_write(raminit->syscon, raminit->reg, ctrl);
+
+ ctrl &= ~(1 << raminit->bits.done);
+ c_can_hw_raminit_wait_syscon(priv, mask, ctrl);
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, mask, ctrl);
+ ctrl |= 1 << raminit->bits.start;
+ regmap_write(raminit->syscon, raminit->reg, ctrl);
+
+ ctrl |= 1 << raminit->bits.done;
+ c_can_hw_raminit_wait_syscon(priv, mask, ctrl);
}
spin_unlock(&raminit_lock);
}
@@ -207,10 +215,11 @@ static int c_can_plat_probe(struct platform_device *pdev)
struct net_device *dev;
struct c_can_priv *priv;
const struct of_device_id *match;
- struct resource *mem, *res;
+ struct resource *mem;
int irq;
struct clk *clk;
const struct c_can_driver_data *drvdata;
+ struct device_node *np = pdev->dev.of_node;
match = of_match_device(c_can_of_table, &pdev->dev);
if (match) {
@@ -278,27 +287,49 @@ static int c_can_plat_probe(struct platform_device *pdev)
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");
- else
- priv->instance = pdev->id;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- /* 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.
+ /* Check if we need custom RAMINIT via syscon. Mostly for TI
+ * platforms. Only supported with DT boot.
*/
- if (!res) {
+ if (np && of_property_read_bool(np, "syscon-raminit")) {
+ u32 id;
+ struct c_can_raminit *raminit = &priv->raminit_sys;
+
+ ret = -EINVAL;
+ raminit->syscon = syscon_regmap_lookup_by_phandle(np,
+ "syscon-raminit");
+ if (IS_ERR(raminit->syscon)) {
+ /* can fail with -EPROBE_DEFER */
+ ret = PTR_ERR(raminit->syscon);
+ free_c_can_dev(dev);
+ return ret;
+ }
+
+ if (of_property_read_u32_index(np, "syscon-raminit", 1,
+ &raminit->reg)) {
+ dev_err(&pdev->dev,
+ "couldn't get the RAMINIT reg. offset!\n");
+ goto exit_free_device;
+ }
+
+ if (of_property_read_u32_index(np, "syscon-raminit", 2,
+ &id)) {
+ dev_err(&pdev->dev,
+ "couldn't get the CAN instance ID\n");
+ goto exit_free_device;
+ }
+
+ if (id >= drvdata->raminit_num) {
+ dev_err(&pdev->dev,
+ "Invalid CAN instance ID\n");
+ goto exit_free_device;
+ }
+
+ raminit->bits = drvdata->raminit_bits[id];
+
+ priv->raminit = c_can_hw_raminit_syscon;
+ } else {
priv->raminit = c_can_hw_raminit;
- break;
}
-
- priv->raminit_ctrlreg = devm_ioremap(&pdev->dev, res->start,
- resource_size(res));
- if (!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_ti;
break;
default:
ret = -EINVAL;