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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/platforms/52xx/mpc52xx_common.c
Initial import
Diffstat (limited to 'arch/powerpc/platforms/52xx/mpc52xx_common.c')
-rw-r--r--arch/powerpc/platforms/52xx/mpc52xx_common.c344
1 files changed, 344 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_common.c b/arch/powerpc/platforms/52xx/mpc52xx_common.c
new file mode 100644
index 000000000..26993826a
--- /dev/null
+++ b/arch/powerpc/platforms/52xx/mpc52xx_common.c
@@ -0,0 +1,344 @@
+/*
+ *
+ * Utility functions for the Freescale MPC52xx.
+ *
+ * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ */
+
+#undef DEBUG
+
+#include <linux/gpio.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+#include <linux/export.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/mpc52xx.h>
+
+/* MPC5200 device tree match tables */
+static const struct of_device_id mpc52xx_xlb_ids[] __initconst = {
+ { .compatible = "fsl,mpc5200-xlb", },
+ { .compatible = "mpc5200-xlb", },
+ {}
+};
+static const struct of_device_id mpc52xx_bus_ids[] __initconst = {
+ { .compatible = "fsl,mpc5200-immr", },
+ { .compatible = "fsl,mpc5200b-immr", },
+ { .compatible = "simple-bus", },
+
+ /* depreciated matches; shouldn't be used in new device trees */
+ { .compatible = "fsl,lpb", },
+ { .type = "builtin", .compatible = "mpc5200", }, /* efika */
+ { .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
+ {}
+};
+
+/*
+ * This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart().
+ * Permanent mapping is required because mpc52xx_restart() can be called
+ * from interrupt context while node mapping (which calls ioremap())
+ * cannot be used at such point.
+ */
+static DEFINE_SPINLOCK(mpc52xx_lock);
+static struct mpc52xx_gpt __iomem *mpc52xx_wdt;
+static struct mpc52xx_cdm __iomem *mpc52xx_cdm;
+
+/*
+ * Configure the XLB arbiter settings to match what Linux expects.
+ */
+void __init
+mpc5200_setup_xlb_arbiter(void)
+{
+ struct device_node *np;
+ struct mpc52xx_xlb __iomem *xlb;
+
+ np = of_find_matching_node(NULL, mpc52xx_xlb_ids);
+ xlb = of_iomap(np, 0);
+ of_node_put(np);
+ if (!xlb) {
+ printk(KERN_ERR __FILE__ ": "
+ "Error mapping XLB in mpc52xx_setup_cpu(). "
+ "Expect some abnormal behavior\n");
+ return;
+ }
+
+ /* Configure the XLB Arbiter priorities */
+ out_be32(&xlb->master_pri_enable, 0xff);
+ out_be32(&xlb->master_priority, 0x11111111);
+
+ /*
+ * Disable XLB pipelining
+ * (cfr errate 292. We could do this only just before ATA PIO
+ * transaction and re-enable it afterwards ...)
+ * Not needed on MPC5200B.
+ */
+ if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR)
+ out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS);
+
+ iounmap(xlb);
+}
+
+/*
+ * This variable is mapped in mpc52xx_map_common_devices and
+ * used in mpc5200_psc_ac97_gpio_reset().
+ */
+static DEFINE_SPINLOCK(gpio_lock);
+struct mpc52xx_gpio __iomem *simple_gpio;
+struct mpc52xx_gpio_wkup __iomem *wkup_gpio;
+
+/**
+ * mpc52xx_declare_of_platform_devices: register internal devices and children
+ * of the localplus bus to the of_platform
+ * bus.
+ */
+void __init mpc52xx_declare_of_platform_devices(void)
+{
+ /* Find all the 'platform' devices and register them. */
+ if (of_platform_populate(NULL, mpc52xx_bus_ids, NULL, NULL))
+ pr_err(__FILE__ ": Error while populating devices from DT\n");
+}
+
+/*
+ * match tables used by mpc52xx_map_common_devices()
+ */
+static const struct of_device_id mpc52xx_gpt_ids[] __initconst = {
+ { .compatible = "fsl,mpc5200-gpt", },
+ { .compatible = "mpc5200-gpt", }, /* old */
+ {}
+};
+static const struct of_device_id mpc52xx_cdm_ids[] __initconst = {
+ { .compatible = "fsl,mpc5200-cdm", },
+ { .compatible = "mpc5200-cdm", }, /* old */
+ {}
+};
+static const struct of_device_id mpc52xx_gpio_simple[] __initconst = {
+ { .compatible = "fsl,mpc5200-gpio", },
+ {}
+};
+static const struct of_device_id mpc52xx_gpio_wkup[] __initconst = {
+ { .compatible = "fsl,mpc5200-gpio-wkup", },
+ {}
+};
+
+
+/**
+ * mpc52xx_map_common_devices: iomap devices required by common code
+ */
+void __init
+mpc52xx_map_common_devices(void)
+{
+ struct device_node *np;
+
+ /* mpc52xx_wdt is mapped here and used in mpc52xx_restart,
+ * possibly from a interrupt context. wdt is only implement
+ * on a gpt0, so check has-wdt property before mapping.
+ */
+ for_each_matching_node(np, mpc52xx_gpt_ids) {
+ if (of_get_property(np, "fsl,has-wdt", NULL) ||
+ of_get_property(np, "has-wdt", NULL)) {
+ mpc52xx_wdt = of_iomap(np, 0);
+ of_node_put(np);
+ break;
+ }
+ }
+
+ /* Clock Distribution Module, used by PSC clock setting function */
+ np = of_find_matching_node(NULL, mpc52xx_cdm_ids);
+ mpc52xx_cdm = of_iomap(np, 0);
+ of_node_put(np);
+
+ /* simple_gpio registers */
+ np = of_find_matching_node(NULL, mpc52xx_gpio_simple);
+ simple_gpio = of_iomap(np, 0);
+ of_node_put(np);
+
+ /* wkup_gpio registers */
+ np = of_find_matching_node(NULL, mpc52xx_gpio_wkup);
+ wkup_gpio = of_iomap(np, 0);
+ of_node_put(np);
+}
+
+/**
+ * mpc52xx_set_psc_clkdiv: Set clock divider in the CDM for PSC ports
+ *
+ * @psc_id: id of psc port; must be 1,2,3 or 6
+ * @clkdiv: clock divider value to put into CDM PSC register.
+ */
+int mpc52xx_set_psc_clkdiv(int psc_id, int clkdiv)
+{
+ unsigned long flags;
+ u16 __iomem *reg;
+ u32 val;
+ u32 mask;
+ u32 mclken_div;
+
+ if (!mpc52xx_cdm)
+ return -ENODEV;
+
+ mclken_div = 0x8000 | (clkdiv & 0x1FF);
+ switch (psc_id) {
+ case 1: reg = &mpc52xx_cdm->mclken_div_psc1; mask = 0x20; break;
+ case 2: reg = &mpc52xx_cdm->mclken_div_psc2; mask = 0x40; break;
+ case 3: reg = &mpc52xx_cdm->mclken_div_psc3; mask = 0x80; break;
+ case 6: reg = &mpc52xx_cdm->mclken_div_psc6; mask = 0x10; break;
+ default:
+ return -ENODEV;
+ }
+
+ /* Set the rate and enable the clock */
+ spin_lock_irqsave(&mpc52xx_lock, flags);
+ out_be16(reg, mclken_div);
+ val = in_be32(&mpc52xx_cdm->clk_enables);
+ out_be32(&mpc52xx_cdm->clk_enables, val | mask);
+ spin_unlock_irqrestore(&mpc52xx_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(mpc52xx_set_psc_clkdiv);
+
+/**
+ * mpc52xx_get_xtal_freq - Get SYS_XTAL_IN frequency for a device
+ *
+ * @node: device node
+ *
+ * Returns the frequency of the external oscillator clock connected
+ * to the SYS_XTAL_IN pin, or 0 if it cannot be determined.
+ */
+unsigned int mpc52xx_get_xtal_freq(struct device_node *node)
+{
+ u32 val;
+ unsigned int freq;
+
+ if (!mpc52xx_cdm)
+ return 0;
+
+ freq = mpc5xxx_get_bus_frequency(node);
+ if (!freq)
+ return 0;
+
+ if (in_8(&mpc52xx_cdm->ipb_clk_sel) & 0x1)
+ freq *= 2;
+
+ val = in_be32(&mpc52xx_cdm->rstcfg);
+ if (val & (1 << 5))
+ freq *= 8;
+ else
+ freq *= 4;
+ if (val & (1 << 6))
+ freq /= 12;
+ else
+ freq /= 16;
+
+ return freq;
+}
+EXPORT_SYMBOL(mpc52xx_get_xtal_freq);
+
+/**
+ * mpc52xx_restart: ppc_md->restart hook for mpc5200 using the watchdog timer
+ */
+void
+mpc52xx_restart(char *cmd)
+{
+ local_irq_disable();
+
+ /* Turn on the watchdog and wait for it to expire.
+ * It effectively does a reset. */
+ if (mpc52xx_wdt) {
+ out_be32(&mpc52xx_wdt->mode, 0x00000000);
+ out_be32(&mpc52xx_wdt->count, 0x000000ff);
+ out_be32(&mpc52xx_wdt->mode, 0x00009004);
+ } else
+ printk(KERN_ERR __FILE__ ": "
+ "mpc52xx_restart: Can't access wdt. "
+ "Restart impossible, system halted.\n");
+
+ while (1);
+}
+
+#define PSC1_RESET 0x1
+#define PSC1_SYNC 0x4
+#define PSC1_SDATA_OUT 0x1
+#define PSC2_RESET 0x2
+#define PSC2_SYNC (0x4<<4)
+#define PSC2_SDATA_OUT (0x1<<4)
+#define MPC52xx_GPIO_PSC1_MASK 0x7
+#define MPC52xx_GPIO_PSC2_MASK (0x7<<4)
+
+/**
+ * mpc5200_psc_ac97_gpio_reset: Use gpio pins to reset the ac97 bus
+ *
+ * @psc: psc number to reset (only psc 1 and 2 support ac97)
+ */
+int mpc5200_psc_ac97_gpio_reset(int psc_number)
+{
+ unsigned long flags;
+ u32 gpio;
+ u32 mux;
+ int out;
+ int reset;
+ int sync;
+
+ if ((!simple_gpio) || (!wkup_gpio))
+ return -ENODEV;
+
+ switch (psc_number) {
+ case 0:
+ reset = PSC1_RESET; /* AC97_1_RES */
+ sync = PSC1_SYNC; /* AC97_1_SYNC */
+ out = PSC1_SDATA_OUT; /* AC97_1_SDATA_OUT */
+ gpio = MPC52xx_GPIO_PSC1_MASK;
+ break;
+ case 1:
+ reset = PSC2_RESET; /* AC97_2_RES */
+ sync = PSC2_SYNC; /* AC97_2_SYNC */
+ out = PSC2_SDATA_OUT; /* AC97_2_SDATA_OUT */
+ gpio = MPC52xx_GPIO_PSC2_MASK;
+ break;
+ default:
+ pr_err(__FILE__ ": Unable to determine PSC, no ac97 "
+ "cold-reset will be performed\n");
+ return -ENODEV;
+ }
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ /* Reconfiure pin-muxing to gpio */
+ mux = in_be32(&simple_gpio->port_config);
+ out_be32(&simple_gpio->port_config, mux & (~gpio));
+
+ /* enable gpio pins for output */
+ setbits8(&wkup_gpio->wkup_gpioe, reset);
+ setbits32(&simple_gpio->simple_gpioe, sync | out);
+
+ setbits8(&wkup_gpio->wkup_ddr, reset);
+ setbits32(&simple_gpio->simple_ddr, sync | out);
+
+ /* Assert cold reset */
+ clrbits32(&simple_gpio->simple_dvo, sync | out);
+ clrbits8(&wkup_gpio->wkup_dvo, reset);
+
+ /* wait for 1 us */
+ udelay(1);
+
+ /* Deassert reset */
+ setbits8(&wkup_gpio->wkup_dvo, reset);
+
+ /* wait at least 200ns */
+ /* 7 ~= (200ns * timebase) / ns2sec */
+ __delay(7);
+
+ /* Restore pin-muxing */
+ out_be32(&simple_gpio->port_config, mux);
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(mpc5200_psc_ac97_gpio_reset);