initial_commit

1 files changed, 284 insertions, 0 deletions

diff --git a/arch/arm/mach-mx5/system.c b/arch/arm/mach-mx5/system.c
new file mode 100755
index 00000000..70667446
--- /dev/null
+++ b/arch/arm/mach-mx5/system.c
@@ -0,0 +1,284 @@
+/*
+ * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <mach/hardware.h>
+#include "crm_regs.h"
+
+/* set cpu low power mode before WFI instruction. This function is called
+  * mx5 because it can be used for mx50, mx51, and mx53.*/
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <asm/io.h>
+#include <mach/common.h>
+#include <mach/hardware.h>
+#include <mach/clock.h>
+#include <asm/proc-fns.h>
+#include <asm/system.h>
+#include "crm_regs.h"
+
+/*!
+ * @defgroup MSL_MX51 i.MX51 Machine Specific Layer (MSL)
+ */
+
+/*!
+ * @file mach-mx51/system.c
+ * @brief This file contains idle and reset functions.
+ *
+ * @ingroup MSL_MX51
+ */
+
+extern int mxc_jtag_enabled;
+extern int iram_ready;
+extern int dvfs_core_is_active;
+extern void __iomem *ccm_base;
+extern void __iomem *databahn_base;
+extern int low_bus_freq_mode;
+extern void (*wait_in_iram)(void *ccm_addr, void *databahn_addr);
+extern void mx50_wait(u32 ccm_base, u32 databahn_addr);
+extern void stop_dvfs(void);
+extern void *wait_in_iram_base;
+extern void __iomem *apll_base;
+
+static struct clk *gpc_dvfs_clk;
+static struct regulator *vpll;
+static struct clk *pll1_sw_clk;
+static struct clk *osc;
+static struct clk *pll1_main_clk;
+static struct clk *ddr_clk ;
+static int dvfs_core_paused;
+
+/* set cpu low power mode before WFI instruction */
+void mxc_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
+{
+	u32 plat_lpc, arm_srpgcr, ccm_clpcr;
+	u32 empgc0, empgc1;
+	int stop_mode = 0;
+
+	/* always allow platform to issue a deep sleep mode request */
+	plat_lpc = __raw_readl(MXC_CORTEXA8_PLAT_LPC) &
+	    ~(MXC_CORTEXA8_PLAT_LPC_DSM);
+	ccm_clpcr = __raw_readl(MXC_CCM_CLPCR) & ~(MXC_CCM_CLPCR_LPM_MASK);
+	arm_srpgcr = __raw_readl(MXC_SRPG_ARM_SRPGCR) & ~(MXC_SRPGCR_PCR);
+	empgc0 = __raw_readl(MXC_SRPG_EMPGC0_SRPGCR) & ~(MXC_SRPGCR_PCR);
+	empgc1 = __raw_readl(MXC_SRPG_EMPGC1_SRPGCR) & ~(MXC_SRPGCR_PCR);
+
+	switch (mode) {
+	case WAIT_CLOCKED:
+		break;
+	case WAIT_UNCLOCKED:
+		ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET;
+		break;
+	case WAIT_UNCLOCKED_POWER_OFF:
+	case STOP_POWER_OFF:
+		plat_lpc |= MXC_CORTEXA8_PLAT_LPC_DSM
+			    | MXC_CORTEXA8_PLAT_LPC_DBG_DSM;
+		if (mode == WAIT_UNCLOCKED_POWER_OFF) {
+			ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET;
+			ccm_clpcr &= ~MXC_CCM_CLPCR_VSTBY;
+			ccm_clpcr &= ~MXC_CCM_CLPCR_SBYOS;
+			stop_mode = 0;
+		} else {
+			ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET;
+			ccm_clpcr |= 0x3 << MXC_CCM_CLPCR_STBY_COUNT_OFFSET;
+			ccm_clpcr |= MXC_CCM_CLPCR_VSTBY;
+			ccm_clpcr |= MXC_CCM_CLPCR_SBYOS;
+			stop_mode = 1;
+		}
+		arm_srpgcr |= MXC_SRPGCR_PCR;
+
+		if (tzic_enable_wake(1) != 0)
+			return;
+		break;
+	case STOP_POWER_ON:
+		ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET;
+		break;
+	default:
+		printk(KERN_WARNING "UNKNOWN cpu power mode: %d\n", mode);
+		return;
+	}
+
+	__raw_writel(plat_lpc, MXC_CORTEXA8_PLAT_LPC);
+	__raw_writel(ccm_clpcr, MXC_CCM_CLPCR);
+	__raw_writel(arm_srpgcr, MXC_SRPG_ARM_SRPGCR);
+
+	/* Enable NEON SRPG for all but MX50TO1.0. */
+	if (mx50_revision() != IMX_CHIP_REVISION_1_0)
+		__raw_writel(arm_srpgcr, MXC_SRPG_NEON_SRPGCR);
+
+	if (stop_mode) {
+		empgc0 |= MXC_SRPGCR_PCR;
+		empgc1 |= MXC_SRPGCR_PCR;
+
+		__raw_writel(empgc0, MXC_SRPG_EMPGC0_SRPGCR);
+		__raw_writel(empgc1, MXC_SRPG_EMPGC1_SRPGCR);
+	}
+}
+
+/* To change the idle power mode, need to set arch_idle_mode to a different
+ * power mode as in enum mxc_cpu_pwr_mode.
+ * May allow dynamically changing the idle mode.
+ */
+static int arch_idle_mode = WAIT_UNCLOCKED_POWER_OFF;
+/*!
+ * This function puts the CPU into idle mode. It is called by default_idle()
+ * in process.c file.
+ */
+void arch_idle(void)
+{
+	if (likely(!mxc_jtag_enabled)) {
+		if (ddr_clk == NULL)
+			ddr_clk = clk_get(NULL, "ddr_clk");
+		if (gpc_dvfs_clk == NULL)
+			gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs_clk");
+		/* gpc clock is needed for SRPG */
+		clk_enable(gpc_dvfs_clk);
+		mxc_cpu_lp_set(arch_idle_mode);
+
+		if (cpu_is_mx50() && (clk_get_usecount(ddr_clk) == 0)) {
+			memcpy(wait_in_iram_base, mx50_wait, SZ_4K);
+			wait_in_iram = (void *)wait_in_iram_base;
+			if (low_bus_freq_mode) {
+				u32 reg, cpu_podf;
+
+				reg = __raw_readl(apll_base + 0x50);
+				reg = 0x120490;
+				__raw_writel(reg, apll_base + 0x50);
+				reg = __raw_readl(apll_base + 0x80);
+				reg |= 1;
+				__raw_writel(reg, apll_base + 0x80);
+
+				/* Move ARM to be sourced from 24MHz XTAL.
+				 * when ARM is in WFI.
+				 */
+				if (pll1_sw_clk == NULL)
+					pll1_sw_clk = clk_get(NULL,
+							"pll1_sw_clk");
+				if (osc == NULL)
+					osc = clk_get(NULL, "lp_apm");
+				if (pll1_main_clk == NULL)
+					pll1_main_clk = clk_get(NULL,
+							"pll1_main_clk");
+
+				clk_set_parent(pll1_sw_clk, osc);
+				/* Set the ARM-PODF divider to 1. */
+				cpu_podf = __raw_readl(MXC_CCM_CACRR);
+				__raw_writel(0x01, MXC_CCM_CACRR);
+
+				wait_in_iram(ccm_base, databahn_base);
+
+				/* Set the ARM-POD divider back
+				 * to the original.
+				 */
+				__raw_writel(cpu_podf, MXC_CCM_CACRR);
+				clk_set_parent(pll1_sw_clk, pll1_main_clk);
+			} else
+				wait_in_iram(ccm_base, databahn_base);
+		} else
+			cpu_do_idle();
+		clk_disable(gpc_dvfs_clk);
+		clk_put(ddr_clk);
+	}
+}
+
+static int __mxs_reset_block(void __iomem *hwreg, int just_enable)
+{
+	u32 c;
+	int timeout;
+
+	/* the process of software reset of IP block is done
+	   in several steps:
+
+	   - clear SFTRST and wait for block is enabled;
+	   - clear clock gating (CLKGATE bit);
+	   - set the SFTRST again and wait for block is in reset;
+	   - clear SFTRST and wait for reset completion.
+	 */
+	c = __raw_readl(hwreg);
+	c &= ~(1 << 31);	/* clear SFTRST */
+	__raw_writel(c, hwreg);
+	for (timeout = 1000000; timeout > 0; timeout--)
+		/* still in SFTRST state ? */
+		if ((__raw_readl(hwreg) & (1 << 31)) == 0)
+			break;
+	if (timeout <= 0) {
+		printk(KERN_ERR "%s(%p): timeout when enabling\n",
+		       __func__, hwreg);
+		return -ETIME;
+	}
+
+	c = __raw_readl(hwreg);
+	c &= ~(1 << 30);	/* clear CLKGATE */
+	__raw_writel(c, hwreg);
+
+	if (!just_enable) {
+		c = __raw_readl(hwreg);
+		c |= (1 << 31);	/* now again set SFTRST */
+		__raw_writel(c, hwreg);
+		for (timeout = 1000000; timeout > 0; timeout--)
+			/* poll until CLKGATE set */
+			if (__raw_readl(hwreg) & (1 << 30))
+				break;
+		if (timeout <= 0) {
+			printk(KERN_ERR "%s(%p): timeout when resetting\n",
+			       __func__, hwreg);
+			return -ETIME;
+		}
+
+		c = __raw_readl(hwreg);
+		c &= ~(1 << 31);	/* clear SFTRST */
+		__raw_writel(c, hwreg);
+		for (timeout = 1000000; timeout > 0; timeout--)
+			/* still in SFTRST state ? */
+			if ((__raw_readl(hwreg) & (1 << 31)) == 0)
+				break;
+		if (timeout <= 0) {
+			printk(KERN_ERR "%s(%p): timeout when enabling "
+			       "after reset\n", __func__, hwreg);
+			return -ETIME;
+		}
+
+		c = __raw_readl(hwreg);
+		c &= ~(1 << 30);	/* clear CLKGATE */
+		__raw_writel(c, hwreg);
+	}
+	for (timeout = 1000000; timeout > 0; timeout--)
+		/* still in SFTRST state ? */
+		if ((__raw_readl(hwreg) & (1 << 30)) == 0)
+			break;
+
+	if (timeout <= 0) {
+		printk(KERN_ERR "%s(%p): timeout when unclockgating\n",
+		       __func__, hwreg);
+		return -ETIME;
+	}
+
+	return 0;
+}
+
+int mxs_reset_block(void __iomem *hwreg, int just_enable)
+{
+	int try = 10;
+	int r;
+
+	while (try--) {
+		r = __mxs_reset_block(hwreg, just_enable);
+		if (!r)
+			break;
+		pr_debug("%s: try %d failed\n", __func__, 10 - try);
+	}
+	return r;
+}