diff options
Diffstat (limited to 'arch/arm/mach-mx37/system.c')
-rw-r--r-- | arch/arm/mach-mx37/system.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/arm/mach-mx37/system.c b/arch/arm/mach-mx37/system.c new file mode 100644 index 000000000000..d40549b29ddc --- /dev/null +++ b/arch/arm/mach-mx37/system.c @@ -0,0 +1,192 @@ +/* + * Copyright 2007-2009 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 + */ +#define DEBUG +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <mach/hardware.h> +#include <asm/proc-fns.h> +#include <asm/system.h> +#include <asm/cacheflush.h> +#include <mach/clock.h> +#include "crm_regs.h" + +/*! + * @defgroup MSL_MX37 i.MX37 Machine Specific Layer (MSL) + */ + +/*! + * @file mach-mx37/system.c + * @brief This file contains idle and reset functions. + * + * @ingroup MSL_MX37 + */ + +extern int mxc_jtag_enabled; +extern int low_bus_freq_mode; + +static struct clk *pll1_main; +static struct clk *pll1_sw_clk; +static struct clk *lp_apm_clk; +static struct clk *gpc_dvfs_clk; + +/* set cpu low power mode before WFI instruction */ +void mxc_cpu_lp_set(enum mxc_cpu_pwr_mode mode) +{ + u32 plat_lpc, gpc_pgr, arm_srpgcr, empgcr0, empgcr1, ccm_clpcr; + /* always allow platform to issue a deep sleep mode request */ + plat_lpc = __raw_readl(MXC_ARM1176_PLAT_LPC) & + ~(MXC_ARM1176_PLAT_LPC_DSM); + + ccm_clpcr = __raw_readl(MXC_CCM_CLPCR) & ~(MXC_CCM_CLPCR_LPM_MASK); + gpc_pgr = __raw_readl(MXC_GPC_PGR) & ~(MXC_GPC_PGR_ARMPG_MASK); + arm_srpgcr = __raw_readl(MXC_SRPGC_ARM_SRPGCR) & ~(MXC_SRPGCR_PCR); + empgcr0 = __raw_readl(MXC_EMPGC0_ARM_EMPGCR) & ~(MXC_EMPGCR_PCR); + empgcr1 = __raw_readl(MXC_EMPGC1_ARM_EMPGCR) & ~(MXC_EMPGCR_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_ARM1176_PLAT_LPC_DSM; + if (mode == WAIT_UNCLOCKED_POWER_OFF) + ccm_clpcr |= (0x1 << MXC_CCM_CLPCR_LPM_OFFSET); + 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; + } + + gpc_pgr |= (0x1 << MXC_GPC_PGR_ARMPG_OFFSET); + arm_srpgcr |= MXC_SRPGCR_PCR; + empgcr0 |= MXC_EMPGCR_PCR; + empgcr1 |= MXC_EMPGCR_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_ARM1176_PLAT_LPC); + __raw_writel(ccm_clpcr, MXC_CCM_CLPCR); + __raw_writel(gpc_pgr, MXC_GPC_PGR); + __raw_writel(arm_srpgcr, MXC_SRPGC_ARM_SRPGCR); + if ((mxc_cpu_is_rev(CHIP_REV_1_0)) != 1) + __raw_writel(empgcr0, MXC_EMPGC0_ARM_EMPGCR); + + __raw_writel(empgcr1, MXC_EMPGC1_ARM_EMPGCR); + + flush_cache_all(); + + 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); + if (low_bus_freq_mode) { + if (pll1_sw_clk == NULL) + pll1_sw_clk = clk_get(NULL, "pll1_sw_clk"); + if (lp_apm_clk == NULL) + lp_apm_clk = clk_get(NULL, "lp_apm"); + if (pll1_main == NULL) + pll1_main = clk_get(NULL, "pll1_main_clk"); + + /* Move the ARM to run off the 24MHz clock. Shutdown the PLL1 */ + /* Change the source of pll1_sw_clk to be the step_clk */ + clk_set_parent(pll1_sw_clk, lp_apm_clk); + } +} + +void mxc_pg_enable(struct platform_device *pdev) +{ + if (pdev == NULL) + return; + + if (strcmp(pdev->name, "mxc_ipu") == 0) { + __raw_writel(MXC_PGCR_PCR, MXC_PGC_IPU_PGCR); + __raw_writel(MXC_PGSR_PSR, MXC_PGC_IPU_PGSR); + } else if (strcmp(pdev->name, "mxc_vpu") == 0) { + __raw_writel(MXC_PGCR_PCR, MXC_PGC_VPU_PGCR); + __raw_writel(MXC_PGSR_PSR, MXC_PGC_VPU_PGSR); + } +} + +EXPORT_SYMBOL(mxc_pg_enable); + +void mxc_pg_disable(struct platform_device *pdev) +{ + if (pdev == NULL) + return; + + if (strcmp(pdev->name, "mxc_ipu") == 0) { + __raw_writel(0x0, MXC_PGC_IPU_PGCR); + if (__raw_readl(MXC_PGC_IPU_PGSR) & MXC_PGSR_PSR) + dev_dbg(&pdev->dev, "power gating successful\n"); + __raw_writel(MXC_PGSR_PSR, MXC_PGC_IPU_PGSR); + } else if (strcmp(pdev->name, "mxc_vpu") == 0) { + __raw_writel(0x0, MXC_PGC_VPU_PGCR); + if (__raw_readl(MXC_PGC_VPU_PGSR) & MXC_PGSR_PSR) + dev_dbg(&pdev->dev, "power gating successful\n"); + __raw_writel(MXC_PGSR_PSR, MXC_PGC_VPU_PGSR); + } +} + +EXPORT_SYMBOL(mxc_pg_disable); + +/* 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)) { + mxc_cpu_lp_set(arch_idle_mode); + cpu_do_idle(); + /* gpc clock is needed for SRPG */ + clk_disable(gpc_dvfs_clk); + if (low_bus_freq_mode) { + /* Move ARM back to PLL from step clk. */ + /* Move the PLL1 back to the pll1_main_clk */ + clk_set_parent(pll1_sw_clk, pll1_main); + } + } +} + +/* + * This function resets the system. It is called by machine_restart(). + * + * @param mode indicates different kinds of resets + */ +void arch_reset(char mode) +{ + /* Assert SRS signal */ + mxc_wd_reset(); +} |