diff options
Diffstat (limited to 'arch/arm/mach-imx/busfreq_lpddr2.c')
| -rw-r--r-- | arch/arm/mach-imx/busfreq_lpddr2.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/busfreq_lpddr2.c b/arch/arm/mach-imx/busfreq_lpddr2.c new file mode 100644 index 000000000000..2ef1806bbc35 --- /dev/null +++ b/arch/arm/mach-imx/busfreq_lpddr2.c @@ -0,0 +1,373 @@ +/* + * Copyright (C) 2011-2016 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2017 NXP. + */ + +/* + * 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 + */ + +/*! + * @file busfreq_lpddr2.c + * + * @brief iMX6 LPDDR2 frequency change specific file. + * + * @ingroup PM + */ +#include <asm/cacheflush.h> +#include <asm/fncpy.h> +#include <asm/io.h> +#include <asm/mach/map.h> +#include <asm/mach-types.h> +#include <asm/tlb.h> +#include <linux/busfreq-imx.h> +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/cpumask.h> +#include <linux/delay.h> +#include <linux/genalloc.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip/arm-gic.h> +#include <linux/kernel.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/proc_fs.h> +#include <linux/sched.h> +#include <linux/smp.h> +#include <linux/slab.h> + +#include "common.h" +#include "hardware.h" + +static struct device *busfreq_dev; +static int curr_ddr_rate; +static DEFINE_SPINLOCK(freq_lock); + +void (*mx6_change_lpddr2_freq)(u32 ddr_freq, int bus_freq_mode) = NULL; + +extern unsigned int ddr_normal_rate; +extern void mx6_lpddr2_freq_change(u32 freq, int bus_freq_mode); +extern void imx6_up_lpddr2_freq_change(u32 freq, int bus_freq_mode); +extern void imx6sll_lpddr2_freq_change(u32 freq, int bus_freq_mode); +extern unsigned long save_ttbr1(void); +extern void restore_ttbr1(unsigned long ttbr1); +extern void mx6q_lpddr2_freq_change(u32 freq, void *ddr_settings); +extern unsigned long ddr_freq_change_iram_base; +extern unsigned long imx6_lpddr2_freq_change_start asm("imx6_lpddr2_freq_change_start"); +extern unsigned long imx6_lpddr2_freq_change_end asm("imx6_lpddr2_freq_change_end"); +extern unsigned long mx6q_lpddr2_freq_change_start asm("mx6q_lpddr2_freq_change_start"); +extern unsigned long mx6q_lpddr2_freq_change_end asm("mx6q_lpddr2_freq_change_end"); +extern unsigned long iram_tlb_phys_addr; + +struct mmdc_settings_info { + u32 size; + void *settings; + int freq; +} __aligned(8); +static struct mmdc_settings_info *mmdc_settings_info; +void (*mx6_change_lpddr2_freq_smp)(u32 ddr_freq, struct mmdc_settings_info + *mmdc_settings_info) = NULL; + +static int mmdc_settings_size; +static unsigned long (*mmdc_settings)[2]; +static unsigned long (*iram_mmdc_settings)[2]; +static unsigned long *iram_settings_size; +static unsigned long *iram_ddr_freq_chage; +unsigned long mmdc_timing_settings[][2] = { + {0x0C, 0x0}, /* mmdc_mdcfg0 */ + {0x10, 0x0}, /* mmdc_mdcfg1 */ + {0x14, 0x0}, /* mmdc_mdcfg2 */ + {0x18, 0x0}, /* mmdc_mdmisc */ + {0x38, 0x0}, /* mmdc_mdcfg3lp */ +}; + +#ifdef CONFIG_SMP +volatile u32 *wait_for_lpddr2_freq_update; +static unsigned int online_cpus; +static u32 *irqs_used; +void (*wfe_change_lpddr2_freq)(u32 cpuid, u32 *ddr_freq_change_done); +extern void wfe_smp_freq_change(u32 cpuid, u32 *ddr_freq_change_done); +extern unsigned long wfe_smp_freq_change_start asm("wfe_smp_freq_change_start"); +extern unsigned long wfe_smp_freq_change_end asm("wfe_smp_freq_change_end"); +extern void __iomem *imx_scu_base; +static void __iomem *gic_dist_base; +#endif + +#ifdef CONFIG_SMP +static irqreturn_t wait_in_wfe_irq(int irq, void *dev_id) +{ + u32 me; + + me = smp_processor_id(); +#ifdef CONFIG_LOCAL_TIMERS + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &me); +#endif + wfe_change_lpddr2_freq(0xff << (me * 8), + (u32 *)ddr_freq_change_iram_base); +#ifdef CONFIG_LOCAL_TIMERS + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &me); +#endif + return IRQ_HANDLED; +} +#endif + +/* change the DDR frequency. */ +int update_lpddr2_freq(int ddr_rate) +{ + unsigned long ttbr1, flags; + int mode = get_bus_freq_mode(); + + if (ddr_rate == curr_ddr_rate) + return 0; + + printk(KERN_DEBUG "\nBus freq set to %d start...\n", ddr_rate); + + spin_lock_irqsave(&freq_lock, flags); + /* + * Flush the TLB, to ensure no TLB maintenance occurs + * when DDR is in self-refresh. + */ + ttbr1 = save_ttbr1(); + + /* Now change DDR frequency. */ + if (cpu_is_imx6sl()) + mx6_change_lpddr2_freq(ddr_rate, + (mode == BUS_FREQ_LOW || mode == BUS_FREQ_ULTRA_LOW) ? 1 : 0); + else + mx6_change_lpddr2_freq(ddr_rate, + (mode == BUS_FREQ_LOW || mode == BUS_FREQ_AUDIO) ? 1 : 0); + + restore_ttbr1(ttbr1); + + curr_ddr_rate = ddr_rate; + spin_unlock_irqrestore(&freq_lock, flags); + + printk(KERN_DEBUG "\nBus freq set to %d done...\n", ddr_rate); + + return 0; +} + +int init_mmdc_lpddr2_settings(struct platform_device *busfreq_pdev) +{ + unsigned long ddr_code_size; + busfreq_dev = &busfreq_pdev->dev; + + ddr_code_size = SZ_4K; + + if (cpu_is_imx6sl()) + mx6_change_lpddr2_freq = (void *)fncpy( + (void *)ddr_freq_change_iram_base, + &mx6_lpddr2_freq_change, ddr_code_size); + if (cpu_is_imx6sx() || cpu_is_imx6ul() || cpu_is_imx6ull()) + mx6_change_lpddr2_freq = (void *)fncpy( + (void *)ddr_freq_change_iram_base, + &imx6_up_lpddr2_freq_change, ddr_code_size); + if (cpu_is_imx6sll()) + mx6_change_lpddr2_freq = (void *)fncpy( + (void *)ddr_freq_change_iram_base, + &imx6sll_lpddr2_freq_change, ddr_code_size); + + curr_ddr_rate = ddr_normal_rate; + + return 0; +} + +int update_lpddr2_freq_smp(int ddr_rate) +{ + unsigned long ttbr1; + int i, me = 0; +#ifdef CONFIG_SMP + int cpu = 0; + u32 reg = 0; +#endif + + if (ddr_rate == curr_ddr_rate) + return 0; + + printk(KERN_DEBUG "Bus freq set to %d start...\n", ddr_rate); + + for (i=0; i < mmdc_settings_size; i++) { + iram_mmdc_settings[i][0] = mmdc_settings[i][0]; + iram_mmdc_settings[i][1] = mmdc_settings[i][1]; + } + + mmdc_settings_info->size = mmdc_settings_size; + mmdc_settings_info->settings = iram_mmdc_settings; + mmdc_settings_info->freq = curr_ddr_rate; + + /* ensure that all Cores are in WFE. */ + local_irq_disable(); + +#ifdef CONFIG_SMP + me = smp_processor_id(); + + /* Make sure all the online cores are active */ + while (1) { + bool not_exited_busfreq = false; + for_each_online_cpu(cpu) { + reg = __raw_readl(imx_scu_base + 0x08); + if (reg & (0x02 << (cpu * 8))) + not_exited_busfreq = true; + } + if (!not_exited_busfreq) + break; + } + + wmb(); + *wait_for_lpddr2_freq_update = 1; + dsb(); + online_cpus = readl_relaxed(imx_scu_base + 0x08); + for_each_online_cpu(cpu) { + *((char *)(&online_cpus) + (u8)cpu) = 0x02; + if (cpu != me) { + reg = 1 << (irqs_used[cpu] % 32); + writel_relaxed(reg, gic_dist_base + GIC_DIST_PENDING_SET + + (irqs_used[cpu] / 32) * 4); + } + } + + /* Wait for the other active CPUs to idle */ + while (1) { + reg = 0; + reg = readl_relaxed(imx_scu_base + 0x08); + reg |= (0x02 << (me * 8)); + if (reg == online_cpus) + break; + } +#endif + + /* Ensure iram_tlb_phys_addr is flushed to DDR. */ + __cpuc_flush_dcache_area(&iram_tlb_phys_addr, + sizeof(iram_tlb_phys_addr)); + outer_clean_range(__pa(&iram_tlb_phys_addr), + __pa(&iram_tlb_phys_addr + 1)); + /* + * Flush the TLB, to ensure no TLB maintenance occurs + * when DDR is in self-refresh. + */ + ttbr1 = save_ttbr1(); + + curr_ddr_rate = ddr_rate; + + /* Now change DDR frequency. */ + mx6_change_lpddr2_freq_smp(ddr_rate, mmdc_settings_info); + + restore_ttbr1(ttbr1); + +#ifdef CONFIG_SMP + wmb(); + /* DDR frequency change is done . */ + *wait_for_lpddr2_freq_update = 0; + dsb(); + /* wake up all the cores. */ + sev(); +#endif + + local_irq_enable(); + + printk(KERN_DEBUG "Bus freq set to %d done! cpu=%d\n", ddr_rate, me); + + return 0; +} + +int init_mmdc_lpddr2_settings_mx6q(struct platform_device *busfreq_pdev) +{ + struct device *dev = &busfreq_pdev->dev; + unsigned long ddr_code_size = 0; + unsigned long wfe_code_size = 0; + struct device_node *node; + void __iomem *mmdc_base; + int i; +#ifdef CONFIG_SMP + struct irq_data *d; + u32 cpu; + int err; +#endif + + node = of_find_compatible_node(NULL, NULL, "fsl,imx6q-mmdc"); + if (!node) { + printk(KERN_ERR "failed to find mmdc device tree data!\n"); + return -EINVAL; + } + + mmdc_base = of_iomap(node, 0); + if (!mmdc_base) { + dev_err(dev, "unable to map mmdc registers\n"); + return -EINVAL; + } + + mmdc_settings_size = ARRAY_SIZE(mmdc_timing_settings); + mmdc_settings = kmalloc((mmdc_settings_size * 8), GFP_KERNEL); + memcpy(mmdc_settings, mmdc_timing_settings, + sizeof(mmdc_timing_settings)); + +#ifdef CONFIG_SMP + node = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-gic"); + if (!node) { + printk(KERN_ERR "failed to find imx6q-a9-gic device tree data!\n"); + return -EINVAL; + } + + gic_dist_base = of_iomap(node, 0); + WARN(!gic_dist_base, "unable to map gic dist registers\n"); + + irqs_used = devm_kzalloc(dev, sizeof(u32) * num_present_cpus(), + GFP_KERNEL); + + for_each_online_cpu(cpu) { + int irq = platform_get_irq(busfreq_pdev, cpu); + err = request_irq(irq, wait_in_wfe_irq, IRQF_PERCPU, + "mmdc_1", NULL); + if (err) { + dev_err(dev, + "Busfreq:request_irq failed %d, err = %d\n", + irq, err); + return err; + } + err = irq_set_affinity(irq, cpumask_of(cpu)); + if (err) { + dev_err(dev, + "Busfreq: Cannot set irq affinity irq=%d,\n", + irq); + return err; + } + d = irq_get_irq_data(irq); + irqs_used[cpu] = d->hwirq + 32; + } + + /* Stoange_iram_basee the variable used to communicate between cores in + * a non-cacheable IRAM area */ + wait_for_lpddr2_freq_update = (u32 *)ddr_freq_change_iram_base; + wfe_code_size = (&wfe_smp_freq_change_end - &wfe_smp_freq_change_start) *4; + + wfe_change_lpddr2_freq = (void *)fncpy((void *)ddr_freq_change_iram_base + 0x8, + &wfe_smp_freq_change, wfe_code_size); +#endif + iram_settings_size = (void *)ddr_freq_change_iram_base + wfe_code_size + 0x8; + iram_mmdc_settings = (void *)iram_settings_size + sizeof(*mmdc_settings_info); + iram_ddr_freq_chage = (void *)iram_mmdc_settings + (mmdc_settings_size * 8) + 0x8; + mmdc_settings_info = (struct mmdc_settings_info *)iram_settings_size; + + ddr_code_size = (&mx6q_lpddr2_freq_change_end -&mx6q_lpddr2_freq_change_start) *4; + + mx6_change_lpddr2_freq_smp = (void *)fncpy(iram_ddr_freq_chage, + &mx6q_lpddr2_freq_change, ddr_code_size); + + /* save initial mmdc boot timing settings */ + for (i=0; i < mmdc_settings_size; i++) + mmdc_settings[i][1] = readl_relaxed(mmdc_base + + mmdc_settings[i][0]); + + curr_ddr_rate = ddr_normal_rate; + + return 0; +} |