diff --git a/Documentation/devicetree/bindings/net/can/c_can.txt b/Documentation/devicetree/bindings/net/can/c_can.txt index 8f1ae81228e3..a3ca3ee53546 100644 --- a/Documentation/devicetree/bindings/net/can/c_can.txt +++ b/Documentation/devicetree/bindings/net/can/c_can.txt @@ -12,6 +12,9 @@ Required properties: Optional properties: - ti,hwmods : Must be "d_can" or "c_can", 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. diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h index 3f111f4f0f6e..28a73d14ea8d 100644 --- a/drivers/net/can/c_can/c_can.h +++ b/drivers/net/can/c_can/c_can.h @@ -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; diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c index 44c293926f78..1fbfa1d59c29 100644 --- a/drivers/net/can/c_can/c_can_platform.c +++ b/drivers/net/can/c_can/c_can_platform.c @@ -32,14 +32,13 @@ #include #include #include +#include +#include #include #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) { - priv->raminit = c_can_hw_raminit; - break; - } + if (np && of_property_read_bool(np, "syscon-raminit")) { + u32 id; + struct c_can_raminit *raminit = &priv->raminit_sys; - 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; + 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; default: ret = -EINVAL;