summaryrefslogtreecommitdiffstats
path: root/drivers/net/can/mscan/mpc5xxx_can.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/can/mscan/mpc5xxx_can.c')
-rw-r--r--drivers/net/can/mscan/mpc5xxx_can.c248
1 files changed, 205 insertions, 43 deletions
diff --git a/drivers/net/can/mscan/mpc5xxx_can.c b/drivers/net/can/mscan/mpc5xxx_can.c
index 1de6f6349b1..03e7c48465a 100644
--- a/drivers/net/can/mscan/mpc5xxx_can.c
+++ b/drivers/net/can/mscan/mpc5xxx_can.c
@@ -29,6 +29,7 @@
#include <linux/can/dev.h>
#include <linux/of_platform.h>
#include <sysdev/fsl_soc.h>
+#include <linux/clk.h>
#include <linux/io.h>
#include <asm/mpc52xx.h>
@@ -36,22 +37,21 @@
#define DRV_NAME "mpc5xxx_can"
-static struct of_device_id mpc52xx_cdm_ids[] __devinitdata = {
+struct mpc5xxx_can_data {
+ unsigned int type;
+ u32 (*get_clock)(struct of_device *ofdev, const char *clock_name,
+ int *mscan_clksrc);
+};
+
+#ifdef CONFIG_PPC_MPC52xx
+static struct of_device_id __devinitdata mpc52xx_cdm_ids[] = {
{ .compatible = "fsl,mpc5200-cdm", },
{}
};
-/*
- * Get frequency of the MSCAN clock source
- *
- * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock (IP_CLK)
- * can be selected. According to the MPC5200 user's manual, the oscillator
- * clock is the better choice as it has less jitter but due to a hardware
- * bug, it can not be selected for the old MPC5200 Rev. A chips.
- */
-
-static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
- int clock_src)
+static u32 __devinit mpc52xx_can_get_clock(struct of_device *ofdev,
+ const char *clock_name,
+ int *mscan_clksrc)
{
unsigned int pvr;
struct mpc52xx_cdm __iomem *cdm;
@@ -61,21 +61,33 @@ static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
pvr = mfspr(SPRN_PVR);
- freq = mpc5xxx_get_bus_frequency(of->node);
+ /*
+ * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
+ * (IP_CLK) can be selected as MSCAN clock source. According to
+ * the MPC5200 user's manual, the oscillator clock is the better
+ * choice as it has less jitter. For this reason, it is selected
+ * by default. Unfortunately, it can not be selected for the old
+ * MPC5200 Rev. A chips due to a hardware bug (check errata).
+ */
+ if (clock_name && strcmp(clock_name, "ip") == 0)
+ *mscan_clksrc = MSCAN_CLKSRC_BUS;
+ else
+ *mscan_clksrc = MSCAN_CLKSRC_XTAL;
+
+ freq = mpc5xxx_get_bus_frequency(ofdev->node);
if (!freq)
return 0;
- if (clock_src == MSCAN_CLKSRC_BUS || pvr == 0x80822011)
+ if (*mscan_clksrc == MSCAN_CLKSRC_BUS || pvr == 0x80822011)
return freq;
/* Determine SYS_XTAL_IN frequency from the clock domain settings */
np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids);
if (!np_cdm) {
- dev_err(&of->dev, "can't get clock node!\n");
+ dev_err(&ofdev->dev, "can't get clock node!\n");
return 0;
}
cdm = of_iomap(np_cdm, 0);
- of_node_put(np_cdm);
if (in_8(&cdm->ipb_clk_sel) & 0x1)
freq *= 2;
@@ -84,26 +96,174 @@ static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
freq *= (val & (1 << 5)) ? 8 : 4;
freq /= (val & (1 << 6)) ? 12 : 16;
+ of_node_put(np_cdm);
iounmap(cdm);
return freq;
}
+#else /* !CONFIG_PPC_MPC52xx */
+static u32 __devinit mpc52xx_can_get_clock(struct of_device *ofdev,
+ const char *clock_name,
+ int *mscan_clksrc)
+{
+ return 0;
+}
+#endif /* CONFIG_PPC_MPC52xx */
+
+#ifdef CONFIG_PPC_MPC512x
+struct mpc512x_clockctl {
+ u32 spmr; /* System PLL Mode Reg */
+ u32 sccr[2]; /* System Clk Ctrl Reg 1 & 2 */
+ u32 scfr1; /* System Clk Freq Reg 1 */
+ u32 scfr2; /* System Clk Freq Reg 2 */
+ u32 reserved;
+ u32 bcr; /* Bread Crumb Reg */
+ u32 pccr[12]; /* PSC Clk Ctrl Reg 0-11 */
+ u32 spccr; /* SPDIF Clk Ctrl Reg */
+ u32 cccr; /* CFM Clk Ctrl Reg */
+ u32 dccr; /* DIU Clk Cnfg Reg */
+ u32 mccr[4]; /* MSCAN Clk Ctrl Reg 1-3 */
+};
+
+static struct of_device_id __devinitdata mpc512x_clock_ids[] = {
+ { .compatible = "fsl,mpc5121-clock", },
+ {}
+};
+
+static u32 __devinit mpc512x_can_get_clock(struct of_device *ofdev,
+ const char *clock_name,
+ int *mscan_clksrc)
+{
+ struct mpc512x_clockctl __iomem *clockctl;
+ struct device_node *np_clock;
+ struct clk *sys_clk, *ref_clk;
+ int plen, clockidx, clocksrc = -1;
+ u32 sys_freq, val, clockdiv = 1, freq = 0;
+ const u32 *pval;
+
+ np_clock = of_find_matching_node(NULL, mpc512x_clock_ids);
+ if (!np_clock) {
+ dev_err(&ofdev->dev, "couldn't find clock node\n");
+ return -ENODEV;
+ }
+ clockctl = of_iomap(np_clock, 0);
+ if (!clockctl) {
+ dev_err(&ofdev->dev, "couldn't map clock registers\n");
+ return 0;
+ }
+
+ /* Determine the MSCAN device index from the physical address */
+ pval = of_get_property(ofdev->node, "reg", &plen);
+ BUG_ON(!pval || plen < sizeof(*pval));
+ clockidx = (*pval & 0x80) ? 1 : 0;
+ if (*pval & 0x2000)
+ clockidx += 2;
+
+ /*
+ * Clock source and divider selection: 3 different clock sources
+ * can be selected: "ip", "ref" or "sys". For the latter two, a
+ * clock divider can be defined as well. If the clock source is
+ * not specified by the device tree, we first try to find an
+ * optimal CAN source clock based on the system clock. If that
+ * is not posslible, the reference clock will be used.
+ */
+ if (clock_name && !strcmp(clock_name, "ip")) {
+ *mscan_clksrc = MSCAN_CLKSRC_IPS;
+ freq = mpc5xxx_get_bus_frequency(ofdev->node);
+ } else {
+ *mscan_clksrc = MSCAN_CLKSRC_BUS;
+
+ pval = of_get_property(ofdev->node,
+ "fsl,mscan-clock-divider", &plen);
+ if (pval && plen == sizeof(*pval))
+ clockdiv = *pval;
+ if (!clockdiv)
+ clockdiv = 1;
+
+ if (!clock_name || !strcmp(clock_name, "sys")) {
+ sys_clk = clk_get(&ofdev->dev, "sys_clk");
+ if (!sys_clk) {
+ dev_err(&ofdev->dev, "couldn't get sys_clk\n");
+ goto exit_unmap;
+ }
+ /* Get and round up/down sys clock rate */
+ sys_freq = 1000000 *
+ ((clk_get_rate(sys_clk) + 499999) / 1000000);
+
+ if (!clock_name) {
+ /* A multiple of 16 MHz would be optimal */
+ if ((sys_freq % 16000000) == 0) {
+ clocksrc = 0;
+ clockdiv = sys_freq / 16000000;
+ freq = sys_freq / clockdiv;
+ }
+ } else {
+ clocksrc = 0;
+ freq = sys_freq / clockdiv;
+ }
+ }
+
+ if (clocksrc < 0) {
+ ref_clk = clk_get(&ofdev->dev, "ref_clk");
+ if (!ref_clk) {
+ dev_err(&ofdev->dev, "couldn't get ref_clk\n");
+ goto exit_unmap;
+ }
+ clocksrc = 1;
+ freq = clk_get_rate(ref_clk) / clockdiv;
+ }
+ }
+
+ /* Disable clock */
+ out_be32(&clockctl->mccr[clockidx], 0x0);
+ if (clocksrc >= 0) {
+ /* Set source and divider */
+ val = (clocksrc << 14) | ((clockdiv - 1) << 17);
+ out_be32(&clockctl->mccr[clockidx], val);
+ /* Enable clock */
+ out_be32(&clockctl->mccr[clockidx], val | 0x10000);
+ }
+
+ /* Enable MSCAN clock domain */
+ val = in_be32(&clockctl->sccr[1]);
+ if (!(val & (1 << 25)))
+ out_be32(&clockctl->sccr[1], val | (1 << 25));
+
+ dev_dbg(&ofdev->dev, "using '%s' with frequency divider %d\n",
+ *mscan_clksrc == MSCAN_CLKSRC_IPS ? "ips_clk" :
+ clocksrc == 1 ? "ref_clk" : "sys_clk", clockdiv);
+
+exit_unmap:
+ of_node_put(np_clock);
+ iounmap(clockctl);
+
+ return freq;
+}
+#else /* !CONFIG_PPC_MPC512x */
+static u32 __devinit mpc512x_can_get_clock(struct of_device *ofdev,
+ const char *clock_name,
+ int *mscan_clksrc)
+{
+ return 0;
+}
+#endif /* CONFIG_PPC_MPC512x */
static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
const struct of_device_id *id)
{
+ struct mpc5xxx_can_data *data = (struct mpc5xxx_can_data *)id->data;
struct device_node *np = ofdev->node;
struct net_device *dev;
struct mscan_priv *priv;
void __iomem *base;
- const char *clk_src;
- int err, irq, clock_src;
+ const char *clock_name = NULL;
+ int irq, mscan_clksrc = 0;
+ int err = -ENOMEM;
- base = of_iomap(ofdev->node, 0);
+ base = of_iomap(np, 0);
if (!base) {
dev_err(&ofdev->dev, "couldn't ioremap\n");
- err = -ENOMEM;
- goto exit_release_mem;
+ return err;
}
irq = irq_of_parse_and_map(np, 0);
@@ -114,37 +274,27 @@ static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
}
dev = alloc_mscandev();
- if (!dev) {
- err = -ENOMEM;
+ if (!dev)
goto exit_dispose_irq;
- }
priv = netdev_priv(dev);
priv->reg_base = base;
dev->irq = irq;
- /*
- * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
- * (IP_CLK) can be selected as MSCAN clock source. According to
- * the MPC5200 user's manual, the oscillator clock is the better
- * choice as it has less jitter. For this reason, it is selected
- * by default.
- */
- clk_src = of_get_property(np, "fsl,mscan-clock-source", NULL);
- if (clk_src && strcmp(clk_src, "ip") == 0)
- clock_src = MSCAN_CLKSRC_BUS;
- else
- clock_src = MSCAN_CLKSRC_XTAL;
- priv->can.clock.freq = mpc52xx_can_clock_freq(ofdev, clock_src);
+ clock_name = of_get_property(np, "fsl,mscan-clock-source", NULL);
+
+ BUG_ON(!data);
+ priv->type = data->type;
+ priv->can.clock.freq = data->get_clock(ofdev, clock_name,
+ &mscan_clksrc);
if (!priv->can.clock.freq) {
- dev_err(&ofdev->dev, "couldn't get MSCAN clock frequency\n");
- err = -ENODEV;
+ dev_err(&ofdev->dev, "couldn't get MSCAN clock properties\n");
goto exit_free_mscan;
}
SET_NETDEV_DEV(dev, &ofdev->dev);
- err = register_mscandev(dev, clock_src);
+ err = register_mscandev(dev, mscan_clksrc);
if (err) {
dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
DRV_NAME, err);
@@ -164,7 +314,7 @@ exit_dispose_irq:
irq_dispose_mapping(irq);
exit_unmap_mem:
iounmap(base);
-exit_release_mem:
+
return err;
}
@@ -225,8 +375,20 @@ static int mpc5xxx_can_resume(struct of_device *ofdev)
}
#endif
+static struct mpc5xxx_can_data __devinitdata mpc5200_can_data = {
+ .type = MSCAN_TYPE_MPC5200,
+ .get_clock = mpc52xx_can_get_clock,
+};
+
+static struct mpc5xxx_can_data __devinitdata mpc5121_can_data = {
+ .type = MSCAN_TYPE_MPC5121,
+ .get_clock = mpc512x_can_get_clock,
+};
+
static struct of_device_id __devinitdata mpc5xxx_can_table[] = {
- {.compatible = "fsl,mpc5200-mscan"},
+ { .compatible = "fsl,mpc5200-mscan", .data = &mpc5200_can_data, },
+ /* Note that only MPC5121 Rev. 2 (and later) is supported */
+ { .compatible = "fsl,mpc5121-mscan", .data = &mpc5121_can_data, },
{},
};
@@ -255,5 +417,5 @@ static void __exit mpc5xxx_can_exit(void)
module_exit(mpc5xxx_can_exit);
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
-MODULE_DESCRIPTION("Freescale MPC5200 CAN driver");
+MODULE_DESCRIPTION("Freescale MPC5xxx CAN driver");
MODULE_LICENSE("GPL v2");