| /* |
| * CAN bus driver for the Freescale MPC5xxx embedded CPU. |
| * |
| * Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>, |
| * Varma Electronics Oy |
| * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> |
| * Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the version 2 of the GNU General Public License |
| * as published by the Free Software Foundation |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/platform_device.h> |
| #include <linux/netdevice.h> |
| #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> |
| |
| #include "mscan.h" |
| |
| #define DRV_NAME "mpc5xxx_can" |
| |
| struct mpc5xxx_can_data { |
| unsigned int type; |
| u32 (*get_clock)(struct platform_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", }, |
| {} |
| }; |
| |
| static u32 __devinit mpc52xx_can_get_clock(struct platform_device *ofdev, |
| const char *clock_name, |
| int *mscan_clksrc) |
| { |
| unsigned int pvr; |
| struct mpc52xx_cdm __iomem *cdm; |
| struct device_node *np_cdm; |
| unsigned int freq; |
| u32 val; |
| |
| pvr = mfspr(SPRN_PVR); |
| |
| /* |
| * 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->dev.of_node); |
| if (!freq) |
| return 0; |
| |
| 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(&ofdev->dev, "can't get clock node!\n"); |
| return 0; |
| } |
| cdm = of_iomap(np_cdm, 0); |
| |
| if (in_8(&cdm->ipb_clk_sel) & 0x1) |
| freq *= 2; |
| val = in_be32(&cdm->rstcfg); |
| |
| 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 platform_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 platform_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 0; |
| } |
| clockctl = of_iomap(np_clock, 0); |
| if (!clockctl) { |
| dev_err(&ofdev->dev, "couldn't map clock registers\n"); |
| goto exit_put; |
| } |
| |
| /* Determine the MSCAN device index from the physical address */ |
| pval = of_get_property(ofdev->dev.of_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->dev.of_node); |
| } else { |
| *mscan_clksrc = MSCAN_CLKSRC_BUS; |
| |
| pval = of_get_property(ofdev->dev.of_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: |
| iounmap(clockctl); |
| exit_put: |
| of_node_put(np_clock); |
| return freq; |
| } |
| #else /* !CONFIG_PPC_MPC512x */ |
| static u32 __devinit mpc512x_can_get_clock(struct platform_device *ofdev, |
| const char *clock_name, |
| int *mscan_clksrc) |
| { |
| return 0; |
| } |
| #endif /* CONFIG_PPC_MPC512x */ |
| |
| static struct of_device_id mpc5xxx_can_table[]; |
| static int __devinit mpc5xxx_can_probe(struct platform_device *ofdev) |
| { |
| const struct of_device_id *match; |
| const struct mpc5xxx_can_data *data; |
| struct device_node *np = ofdev->dev.of_node; |
| struct net_device *dev; |
| struct mscan_priv *priv; |
| void __iomem *base; |
| const char *clock_name = NULL; |
| int irq, mscan_clksrc = 0; |
| int err = -ENOMEM; |
| |
| match = of_match_device(mpc5xxx_can_table, &ofdev->dev); |
| if (!match) |
| return -EINVAL; |
| data = match->data; |
| |
| base = of_iomap(np, 0); |
| if (!base) { |
| dev_err(&ofdev->dev, "couldn't ioremap\n"); |
| return err; |
| } |
| |
| irq = irq_of_parse_and_map(np, 0); |
| if (!irq) { |
| dev_err(&ofdev->dev, "no irq found\n"); |
| err = -ENODEV; |
| goto exit_unmap_mem; |
| } |
| |
| dev = alloc_mscandev(); |
| if (!dev) |
| goto exit_dispose_irq; |
| |
| priv = netdev_priv(dev); |
| priv->reg_base = base; |
| dev->irq = irq; |
| |
| 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 properties\n"); |
| goto exit_free_mscan; |
| } |
| |
| SET_NETDEV_DEV(dev, &ofdev->dev); |
| |
| err = register_mscandev(dev, mscan_clksrc); |
| if (err) { |
| dev_err(&ofdev->dev, "registering %s failed (err=%d)\n", |
| DRV_NAME, err); |
| goto exit_free_mscan; |
| } |
| |
| dev_set_drvdata(&ofdev->dev, dev); |
| |
| dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n", |
| priv->reg_base, dev->irq, priv->can.clock.freq); |
| |
| return 0; |
| |
| exit_free_mscan: |
| free_candev(dev); |
| exit_dispose_irq: |
| irq_dispose_mapping(irq); |
| exit_unmap_mem: |
| iounmap(base); |
| |
| return err; |
| } |
| |
| static int __devexit mpc5xxx_can_remove(struct platform_device *ofdev) |
| { |
| struct net_device *dev = dev_get_drvdata(&ofdev->dev); |
| struct mscan_priv *priv = netdev_priv(dev); |
| |
| dev_set_drvdata(&ofdev->dev, NULL); |
| |
| unregister_mscandev(dev); |
| iounmap(priv->reg_base); |
| irq_dispose_mapping(dev->irq); |
| free_candev(dev); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static struct mscan_regs saved_regs; |
| static int mpc5xxx_can_suspend(struct platform_device *ofdev, pm_message_t state) |
| { |
| struct net_device *dev = dev_get_drvdata(&ofdev->dev); |
| struct mscan_priv *priv = netdev_priv(dev); |
| struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; |
| |
| _memcpy_fromio(&saved_regs, regs, sizeof(*regs)); |
| |
| return 0; |
| } |
| |
| static int mpc5xxx_can_resume(struct platform_device *ofdev) |
| { |
| struct net_device *dev = dev_get_drvdata(&ofdev->dev); |
| struct mscan_priv *priv = netdev_priv(dev); |
| struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; |
| |
| regs->canctl0 |= MSCAN_INITRQ; |
| while (!(regs->canctl1 & MSCAN_INITAK)) |
| udelay(10); |
| |
| regs->canctl1 = saved_regs.canctl1; |
| regs->canbtr0 = saved_regs.canbtr0; |
| regs->canbtr1 = saved_regs.canbtr1; |
| regs->canidac = saved_regs.canidac; |
| |
| /* restore masks, buffers etc. */ |
| _memcpy_toio(®s->canidar1_0, (void *)&saved_regs.canidar1_0, |
| sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0)); |
| |
| regs->canctl0 &= ~MSCAN_INITRQ; |
| regs->cantbsel = saved_regs.cantbsel; |
| regs->canrier = saved_regs.canrier; |
| regs->cantier = saved_regs.cantier; |
| regs->canctl0 = saved_regs.canctl0; |
| |
| return 0; |
| } |
| #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", .data = &mpc5200_can_data, }, |
| /* Note that only MPC5121 Rev. 2 (and later) is supported */ |
| { .compatible = "fsl,mpc5121-mscan", .data = &mpc5121_can_data, }, |
| {}, |
| }; |
| |
| static struct platform_driver mpc5xxx_can_driver = { |
| .driver = { |
| .name = "mpc5xxx_can", |
| .owner = THIS_MODULE, |
| .of_match_table = mpc5xxx_can_table, |
| }, |
| .probe = mpc5xxx_can_probe, |
| .remove = __devexit_p(mpc5xxx_can_remove), |
| #ifdef CONFIG_PM |
| .suspend = mpc5xxx_can_suspend, |
| .resume = mpc5xxx_can_resume, |
| #endif |
| }; |
| |
| module_platform_driver(mpc5xxx_can_driver); |
| |
| MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); |
| MODULE_DESCRIPTION("Freescale MPC5xxx CAN driver"); |
| MODULE_LICENSE("GPL v2"); |