[PATCH 5/5] can: flexcan: add mcf5441x support

Angelo Dureghello
2021-06-08T20:46:39Z

Add flexcan support for NXP ColdFire mcf5441x family.

This flexcan module is quite similar to imx6 flexcan module, but
with some exceptions:

- 3 separate interrupt sources, MB, BOFF and ERR,
- implements 16 mb only,
- m68k architecture is not supporting devicetrees, so a
platform data check/case has been added,
- ColdFire is m68k, so big-endian cpu, with a little-endian flexcan
module.

Signed-off-by: Angelo Dureghello <angelo@kernel-space.org>
---
drivers/net/can/flexcan.c | 80 +++++++++++++++++++++++++++++++--------
1 file changed, 65 insertions(+), 15 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 57f3635ad8d7..af95273327cd 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -28,6 +28,7 @@
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
+#include <linux/platform_data/flexcan-mcf.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
@@ -205,6 +206,10 @@

#define FLEXCAN_TIMEOUT_US (250)

+#define FLEXCAN_OFFS_INT_BOFF 1
+#define FLEXCAN_OFFS_INT_ERR 3
+#define FLEXCAN_MB_CNT_MCF 16
+
/* FLEXCAN hardware feature flags
*
* Below is some version info we got:
@@ -246,6 +251,8 @@
#define FLEXCAN_QUIRK_SUPPORT_ECC BIT(10)
/* Setup stop mode with SCU firmware to support wakeup */
#define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW BIT(11)
+/* Setup for flexcan module as in mcf, 16 mb, 3 separate interrupts */
+#define FLEXCAN_QUIRK_SETUP_MCF BIT(12)

/* Structure of the message buffer */
struct flexcan_mb {
@@ -371,6 +378,12 @@ struct flexcan_priv {
void (*write)(u32 val, void __iomem *addr);
};

+static const struct flexcan_devtype_data fsl_mcf_devtype_data = {
+ .quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
+ FLEXCAN_QUIRK_BROKEN_PERR_STATE |
+ FLEXCAN_QUIRK_SETUP_MCF,
+};
+
static const struct flexcan_devtype_data fsl_p1010_devtype_data = {
.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
FLEXCAN_QUIRK_BROKEN_PERR_STATE |
@@ -637,13 +650,17 @@ static int flexcan_clks_enable(const struct flexcan_priv *priv)
{
int err;

- err = clk_prepare_enable(priv->clk_ipg);
- if (err)
- return err;
+ if (priv->clk_ipg) {
+ err = clk_prepare_enable(priv->clk_ipg);
+ if (err)
+ return err;
+ }

- err = clk_prepare_enable(priv->clk_per);
- if (err)
- clk_disable_unprepare(priv->clk_ipg);
+ if (priv->clk_per) {
+ err = clk_prepare_enable(priv->clk_per);
+ if (err)
+ clk_disable_unprepare(priv->clk_ipg);
+ }

return err;
}
@@ -1401,8 +1418,13 @@ static int flexcan_rx_offload_setup(struct net_device *dev)
priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
else
priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
- priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
- (sizeof(priv->regs->mb[1]) / priv->mb_size);
+
+ if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SETUP_MCF) {
+ priv->mb_count = FLEXCAN_MB_CNT_MCF;
+ } else {
+ priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
+ (sizeof(priv->regs->mb[1]) / priv->mb_size);
+ }

if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
priv->tx_mb_reserved =
@@ -1774,6 +1796,18 @@ static int flexcan_open(struct net_device *dev)
if (err)
goto out_can_rx_offload_disable;

+ if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SETUP_MCF) {
+ err = request_irq(dev->irq + FLEXCAN_OFFS_INT_BOFF,
+ flexcan_irq, IRQF_SHARED, dev->name, dev);
+ if (err)
+ goto out_can_rx_offload_disable;
+
+ err = request_irq(dev->irq + FLEXCAN_OFFS_INT_ERR,
+ flexcan_irq, IRQF_SHARED, dev->name, dev);
+ if (err)
+ goto out_can_rx_offload_disable;
+ }
+
flexcan_chip_interrupts_enable(dev);

can_led_event(dev, CAN_LED_EVENT_OPEN);
@@ -2047,7 +2081,9 @@ static int flexcan_probe(struct platform_device *pdev)
struct regulator *reg_xceiver;
struct clk *clk_ipg = NULL, *clk_per = NULL;
struct flexcan_regs __iomem *regs;
+ struct mcf_flexcan_platform_data *pdata;
int err, irq;
+ bool big_endian_module;
u8 clk_src = 1;
u32 clock_freq = 0;

@@ -2059,11 +2095,17 @@ static int flexcan_probe(struct platform_device *pdev)
else if (IS_ERR(reg_xceiver))
return PTR_ERR(reg_xceiver);

- if (pdev->dev.of_node) {
- of_property_read_u32(pdev->dev.of_node,
- "clock-frequency", &clock_freq);
- of_property_read_u8(pdev->dev.of_node,
- "fsl,clk-source", &clk_src);
+ pdata = dev_get_platdata(&pdev->dev);
+ if (pdata) {
+ clock_freq = pdata->clock_frequency;
+ clk_src = pdata->clk_src;
+ } else {
+ if (pdev->dev.of_node) {
+ of_property_read_u32(pdev->dev.of_node,
+ "clock-frequency", &clock_freq);
+ of_property_read_u8(pdev->dev.of_node,
+ "fsl,clk-source", &clk_src);
+ }
}

if (!clock_freq) {
@@ -2091,6 +2133,11 @@ static int flexcan_probe(struct platform_device *pdev)

devtype_data = of_device_get_match_data(&pdev->dev);

+ if (pdata && !devtype_data) {
+ devtype_data =
+ (struct flexcan_devtype_data *)&fsl_mcf_devtype_data;
+ }
+
if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
!(devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)) {
dev_err(&pdev->dev, "CAN-FD mode doesn't work with FIFO mode!\n");
@@ -2110,8 +2157,11 @@ static int flexcan_probe(struct platform_device *pdev)

priv = netdev_priv(dev);

- if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
- devtype_data->quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
+ big_endian_module = pdata ? pdata->big_endian :
+ of_property_read_bool(pdev->dev.of_node, "big-endian");
+
+ if (big_endian_module ||
+ (devtype_data->quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN)) {
priv->read = flexcan_read_be;
priv->write = flexcan_write_be;
} else {
--
2.31.1