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 1de6f6349b16..03e7c48465a2 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");