| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Markus Mayer | 2848 | 99.79% | 5 | 62.50% |
| Viresh Kumar | 3 | 0.11% | 1 | 12.50% |
| Kees Cook | 2 | 0.07% | 1 | 12.50% |
| Wei Yongjun | 1 | 0.04% | 1 | 12.50% |
| Total | 2854 | 8 |
/* * CPU frequency scaling for Broadcom SoCs with AVS firmware that * supports DVS or DVFS * * Copyright (c) 2016 Broadcom * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation version 2. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ /* * "AVS" is the name of a firmware developed at Broadcom. It derives * its name from the technique called "Adaptive Voltage Scaling". * Adaptive voltage scaling was the original purpose of this firmware. * The AVS firmware still supports "AVS mode", where all it does is * adaptive voltage scaling. However, on some newer Broadcom SoCs, the * AVS Firmware, despite its unchanged name, also supports DFS mode and * DVFS mode. * * In the context of this document and the related driver, "AVS" by * itself always means the Broadcom firmware and never refers to the * technique called "Adaptive Voltage Scaling". * * The Broadcom STB AVS CPUfreq driver provides voltage and frequency * scaling on Broadcom SoCs using AVS firmware with support for DFS and * DVFS. The AVS firmware is running on its own co-processor. The * driver supports both uniprocessor (UP) and symmetric multiprocessor * (SMP) systems which share clock and voltage across all CPUs. * * Actual voltage and frequency scaling is done solely by the AVS * firmware. This driver does not change frequency or voltage itself. * It provides a standard CPUfreq interface to the rest of the kernel * and to userland. It interfaces with the AVS firmware to effect the * requested changes and to report back the current system status in a * way that is expected by existing tools. */ #include <linux/cpufreq.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of_address.h> #include <linux/platform_device.h> #include <linux/semaphore.h> /* Max number of arguments AVS calls take */ #define AVS_MAX_CMD_ARGS 4 /* * This macro is used to generate AVS parameter register offsets. For * x >= AVS_MAX_CMD_ARGS, it returns 0 to protect against accidental memory * access outside of the parameter range. (Offset 0 is the first parameter.) */ #define AVS_PARAM_MULT(x) ((x) < AVS_MAX_CMD_ARGS ? (x) : 0) /* AVS Mailbox Register offsets */ #define AVS_MBOX_COMMAND 0x00 #define AVS_MBOX_STATUS 0x04 #define AVS_MBOX_VOLTAGE0 0x08 #define AVS_MBOX_TEMP0 0x0c #define AVS_MBOX_PV0 0x10 #define AVS_MBOX_MV0 0x14 #define AVS_MBOX_PARAM(x) (0x18 + AVS_PARAM_MULT(x) * sizeof(u32)) #define AVS_MBOX_REVISION 0x28 #define AVS_MBOX_PSTATE 0x2c #define AVS_MBOX_HEARTBEAT 0x30 #define AVS_MBOX_MAGIC 0x34 #define AVS_MBOX_SIGMA_HVT 0x38 #define AVS_MBOX_SIGMA_SVT 0x3c #define AVS_MBOX_VOLTAGE1 0x40 #define AVS_MBOX_TEMP1 0x44 #define AVS_MBOX_PV1 0x48 #define AVS_MBOX_MV1 0x4c #define AVS_MBOX_FREQUENCY 0x50 /* AVS Commands */ #define AVS_CMD_AVAILABLE 0x00 #define AVS_CMD_DISABLE 0x10 #define AVS_CMD_ENABLE 0x11 #define AVS_CMD_S2_ENTER 0x12 #define AVS_CMD_S2_EXIT 0x13 #define AVS_CMD_BBM_ENTER 0x14 #define AVS_CMD_BBM_EXIT 0x15 #define AVS_CMD_S3_ENTER 0x16 #define AVS_CMD_S3_EXIT 0x17 #define AVS_CMD_BALANCE 0x18 /* PMAP and P-STATE commands */ #define AVS_CMD_GET_PMAP 0x30 #define AVS_CMD_SET_PMAP 0x31 #define AVS_CMD_GET_PSTATE 0x40 #define AVS_CMD_SET_PSTATE 0x41 /* Different modes AVS supports (for GET_PMAP/SET_PMAP) */ #define AVS_MODE_AVS 0x0 #define AVS_MODE_DFS 0x1 #define AVS_MODE_DVS 0x2 #define AVS_MODE_DVFS 0x3 /* * PMAP parameter p1 * unused:31-24, mdiv_p0:23-16, unused:15-14, pdiv:13-10 , ndiv_int:9-0 */ #define NDIV_INT_SHIFT 0 #define NDIV_INT_MASK 0x3ff #define PDIV_SHIFT 10 #define PDIV_MASK 0xf #define MDIV_P0_SHIFT 16 #define MDIV_P0_MASK 0xff /* * PMAP parameter p2 * mdiv_p4:31-24, mdiv_p3:23-16, mdiv_p2:15:8, mdiv_p1:7:0 */ #define MDIV_P1_SHIFT 0 #define MDIV_P1_MASK 0xff #define MDIV_P2_SHIFT 8 #define MDIV_P2_MASK 0xff #define MDIV_P3_SHIFT 16 #define MDIV_P3_MASK 0xff #define MDIV_P4_SHIFT 24 #define MDIV_P4_MASK 0xff /* Different P-STATES AVS supports (for GET_PSTATE/SET_PSTATE) */ #define AVS_PSTATE_P0 0x0 #define AVS_PSTATE_P1 0x1 #define AVS_PSTATE_P2 0x2 #define AVS_PSTATE_P3 0x3 #define AVS_PSTATE_P4 0x4 #define AVS_PSTATE_MAX AVS_PSTATE_P4 /* CPU L2 Interrupt Controller Registers */ #define AVS_CPU_L2_SET0 0x04 #define AVS_CPU_L2_INT_MASK BIT(31) /* AVS Command Status Values */ #define AVS_STATUS_CLEAR 0x00 /* Command/notification accepted */ #define AVS_STATUS_SUCCESS 0xf0 /* Command/notification rejected */ #define AVS_STATUS_FAILURE 0xff /* Invalid command/notification (unknown) */ #define AVS_STATUS_INVALID 0xf1 /* Non-AVS modes are not supported */ #define AVS_STATUS_NO_SUPP 0xf2 /* Cannot set P-State until P-Map supplied */ #define AVS_STATUS_NO_MAP 0xf3 /* Cannot change P-Map after initial P-Map set */ #define AVS_STATUS_MAP_SET 0xf4 /* Max AVS status; higher numbers are used for debugging */ #define AVS_STATUS_MAX 0xff /* Other AVS related constants */ #define AVS_LOOP_LIMIT 10000 #define AVS_TIMEOUT 300 /* in ms; expected completion is < 10ms */ #define AVS_FIRMWARE_MAGIC 0xa11600d1 #define BRCM_AVS_CPUFREQ_PREFIX "brcmstb-avs" #define BRCM_AVS_CPUFREQ_NAME BRCM_AVS_CPUFREQ_PREFIX "-cpufreq" #define BRCM_AVS_CPU_DATA "brcm,avs-cpu-data-mem" #define BRCM_AVS_CPU_INTR "brcm,avs-cpu-l2-intr" #define BRCM_AVS_HOST_INTR "sw_intr" struct pmap { unsigned int mode; unsigned int p1; unsigned int p2; unsigned int state; }; struct private_data { void __iomem *base; void __iomem *avs_intr_base; struct device *dev; struct completion done; struct semaphore sem; struct pmap pmap; }; static void __iomem *__map_region(const char *name) { struct device_node *np; void __iomem *ptr; np = of_find_compatible_node(NULL, NULL, name); if (!np) return NULL; ptr = of_iomap(np, 0); of_node_put(np); return ptr; } static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send, u32 args[]) { unsigned long time_left = msecs_to_jiffies(AVS_TIMEOUT); void __iomem *base = priv->base; unsigned int i; int ret; u32 val; ret = down_interruptible(&priv->sem); if (ret) return ret; /* * Make sure no other command is currently running: cmd is 0 if AVS * co-processor is idle. Due to the guard above, we should almost never * have to wait here. */ for (i = 0, val = 1; val != 0 && i < AVS_LOOP_LIMIT; i++) val = readl(base + AVS_MBOX_COMMAND); /* Give the caller a chance to retry if AVS is busy. */ if (i == AVS_LOOP_LIMIT) { ret = -EAGAIN; goto out; } /* Clear status before we begin. */ writel(AVS_STATUS_CLEAR, base + AVS_MBOX_STATUS); /* We need to send arguments for this command. */ if (args && is_send) { for (i = 0; i < AVS_MAX_CMD_ARGS; i++) writel(args[i], base + AVS_MBOX_PARAM(i)); } /* Protect from spurious interrupts. */ reinit_completion(&priv->done); /* Now issue the command & tell firmware to wake up to process it. */ writel(cmd, base + AVS_MBOX_COMMAND); writel(AVS_CPU_L2_INT_MASK, priv->avs_intr_base + AVS_CPU_L2_SET0); /* Wait for AVS co-processor to finish processing the command. */ time_left = wait_for_completion_timeout(&priv->done, time_left); /* * If the AVS status is not in the expected range, it means AVS didn't * complete our command in time, and we return an error. Also, if there * is no "time left", we timed out waiting for the interrupt. */ val = readl(base + AVS_MBOX_STATUS); if (time_left == 0 || val == 0 || val > AVS_STATUS_MAX) { dev_err(priv->dev, "AVS command %#x didn't complete in time\n", cmd); dev_err(priv->dev, " Time left: %u ms, AVS status: %#x\n", jiffies_to_msecs(time_left), val); ret = -ETIMEDOUT; goto out; } /* This command returned arguments, so we read them back. */ if (args && !is_send) { for (i = 0; i < AVS_MAX_CMD_ARGS; i++) args[i] = readl(base + AVS_MBOX_PARAM(i)); } /* Clear status to tell AVS co-processor we are done. */ writel(AVS_STATUS_CLEAR, base + AVS_MBOX_STATUS); /* Convert firmware errors to errno's as much as possible. */ switch (val) { case AVS_STATUS_INVALID: ret = -EINVAL; break; case AVS_STATUS_NO_SUPP: ret = -ENOTSUPP; break; case AVS_STATUS_NO_MAP: ret = -ENOENT; break; case AVS_STATUS_MAP_SET: ret = -EEXIST; break; case AVS_STATUS_FAILURE: ret = -EIO; break; } out: up(&priv->sem); return ret; } static irqreturn_t irq_handler(int irq, void *data) { struct private_data *priv = data; /* AVS command completed execution. Wake up __issue_avs_command(). */ complete(&priv->done); return IRQ_HANDLED; } static char *brcm_avs_mode_to_string(unsigned int mode) { switch (mode) { case AVS_MODE_AVS: return "AVS"; case AVS_MODE_DFS: return "DFS"; case AVS_MODE_DVS: return "DVS"; case AVS_MODE_DVFS: return "DVFS"; } return NULL; } static void brcm_avs_parse_p1(u32 p1, unsigned int *mdiv_p0, unsigned int *pdiv, unsigned int *ndiv) { *mdiv_p0 = (p1 >> MDIV_P0_SHIFT) & MDIV_P0_MASK; *pdiv = (p1 >> PDIV_SHIFT) & PDIV_MASK; *ndiv = (p1 >> NDIV_INT_SHIFT) & NDIV_INT_MASK; } static void brcm_avs_parse_p2(u32 p2, unsigned int *mdiv_p1, unsigned int *mdiv_p2, unsigned int *mdiv_p3, unsigned int *mdiv_p4) { *mdiv_p4 = (p2 >> MDIV_P4_SHIFT) & MDIV_P4_MASK; *mdiv_p3 = (p2 >> MDIV_P3_SHIFT) & MDIV_P3_MASK; *mdiv_p2 = (p2 >> MDIV_P2_SHIFT) & MDIV_P2_MASK; *mdiv_p1 = (p2 >> MDIV_P1_SHIFT) & MDIV_P1_MASK; } static int brcm_avs_get_pmap(struct private_data *priv, struct pmap *pmap) { u32 args[AVS_MAX_CMD_ARGS]; int ret; ret = __issue_avs_command(priv, AVS_CMD_GET_PMAP, false, args); if (ret || !pmap) return ret; pmap->mode = args[0]; pmap->p1 = args[1]; pmap->p2 = args[2]; pmap->state = args[3]; return 0; } static int brcm_avs_set_pmap(struct private_data *priv, struct pmap *pmap) { u32 args[AVS_MAX_CMD_ARGS]; args[0] = pmap->mode; args[1] = pmap->p1; args[2] = pmap->p2; args[3] = pmap->state; return __issue_avs_command(priv, AVS_CMD_SET_PMAP, true, args); } static int brcm_avs_get_pstate(struct private_data *priv, unsigned int *pstate) { u32 args[AVS_MAX_CMD_ARGS]; int ret; ret = __issue_avs_command(priv, AVS_CMD_GET_PSTATE, false, args); if (ret) return ret; *pstate = args[0]; return 0; } static int brcm_avs_set_pstate(struct private_data *priv, unsigned int pstate) { u32 args[AVS_MAX_CMD_ARGS]; args[0] = pstate; return __issue_avs_command(priv, AVS_CMD_SET_PSTATE, true, args); } static unsigned long brcm_avs_get_voltage(void __iomem *base) { return readl(base + AVS_MBOX_VOLTAGE1); } static unsigned long brcm_avs_get_frequency(void __iomem *base) { return readl(base + AVS_MBOX_FREQUENCY) * 1000; /* in kHz */ } /* * We determine which frequencies are supported by cycling through all P-states * and reading back what frequency we are running at for each P-state. */ static struct cpufreq_frequency_table * brcm_avs_get_freq_table(struct device *dev, struct private_data *priv) { struct cpufreq_frequency_table *table; unsigned int pstate; int i, ret; /* Remember P-state for later */ ret = brcm_avs_get_pstate(priv, &pstate); if (ret) return ERR_PTR(ret); table = devm_kcalloc(dev, AVS_PSTATE_MAX + 1, sizeof(*table), GFP_KERNEL); if (!table) return ERR_PTR(-ENOMEM); for (i = AVS_PSTATE_P0; i <= AVS_PSTATE_MAX; i++) { ret = brcm_avs_set_pstate(priv, i); if (ret) return ERR_PTR(ret); table[i].frequency = brcm_avs_get_frequency(priv->base); table[i].driver_data = i; } table[i].frequency = CPUFREQ_TABLE_END; /* Restore P-state */ ret = brcm_avs_set_pstate(priv, pstate); if (ret) return ERR_PTR(ret); return table; } /* * To ensure the right firmware is running we need to * - check the MAGIC matches what we expect * - brcm_avs_get_pmap() doesn't return -ENOTSUPP or -EINVAL * We need to set up our interrupt handling before calling brcm_avs_get_pmap()! */ static bool brcm_avs_is_firmware_loaded(struct private_data *priv) { u32 magic; int rc; rc = brcm_avs_get_pmap(priv, NULL); magic = readl(priv->base + AVS_MBOX_MAGIC); return (magic == AVS_FIRMWARE_MAGIC) && (rc != -ENOTSUPP) && (rc != -EINVAL); } static unsigned int brcm_avs_cpufreq_get(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); struct private_data *priv = policy->driver_data; return brcm_avs_get_frequency(priv->base); } static int brcm_avs_target_index(struct cpufreq_policy *policy, unsigned int index) { return brcm_avs_set_pstate(policy->driver_data, policy->freq_table[index].driver_data); } static int brcm_avs_suspend(struct cpufreq_policy *policy) { struct private_data *priv = policy->driver_data; int ret; ret = brcm_avs_get_pmap(priv, &priv->pmap); if (ret) return ret; /* * We can't use the P-state returned by brcm_avs_get_pmap(), since * that's the initial P-state from when the P-map was downloaded to the * AVS co-processor, not necessarily the P-state we are running at now. * So, we get the current P-state explicitly. */ return brcm_avs_get_pstate(priv, &priv->pmap.state); } static int brcm_avs_resume(struct cpufreq_policy *policy) { struct private_data *priv = policy->driver_data; int ret; ret = brcm_avs_set_pmap(priv, &priv->pmap); if (ret == -EEXIST) { struct platform_device *pdev = cpufreq_get_driver_data(); struct device *dev = &pdev->dev; dev_warn(dev, "PMAP was already set\n"); ret = 0; } return ret; } /* * All initialization code that we only want to execute once goes here. Setup * code that can be re-tried on every core (if it failed before) can go into * brcm_avs_cpufreq_init(). */ static int brcm_avs_prepare_init(struct platform_device *pdev) { struct private_data *priv; struct device *dev; int host_irq, ret; dev = &pdev->dev; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->dev = dev; sema_init(&priv->sem, 1); init_completion(&priv->done); platform_set_drvdata(pdev, priv); priv->base = __map_region(BRCM_AVS_CPU_DATA); if (!priv->base) { dev_err(dev, "Couldn't find property %s in device tree.\n", BRCM_AVS_CPU_DATA); return -ENOENT; } priv->avs_intr_base = __map_region(BRCM_AVS_CPU_INTR); if (!priv->avs_intr_base) { dev_err(dev, "Couldn't find property %s in device tree.\n", BRCM_AVS_CPU_INTR); ret = -ENOENT; goto unmap_base; } host_irq = platform_get_irq_byname(pdev, BRCM_AVS_HOST_INTR); if (host_irq < 0) { dev_err(dev, "Couldn't find interrupt %s -- %d\n", BRCM_AVS_HOST_INTR, host_irq); ret = host_irq; goto unmap_intr_base; } ret = devm_request_irq(dev, host_irq, irq_handler, IRQF_TRIGGER_RISING, BRCM_AVS_HOST_INTR, priv); if (ret) { dev_err(dev, "IRQ request failed: %s (%d) -- %d\n", BRCM_AVS_HOST_INTR, host_irq, ret); goto unmap_intr_base; } if (brcm_avs_is_firmware_loaded(priv)) return 0; dev_err(dev, "AVS firmware is not loaded or doesn't support DVFS\n"); ret = -ENODEV; unmap_intr_base: iounmap(priv->avs_intr_base); unmap_base: iounmap(priv->base); return ret; } static int brcm_avs_cpufreq_init(struct cpufreq_policy *policy) { struct cpufreq_frequency_table *freq_table; struct platform_device *pdev; struct private_data *priv; struct device *dev; int ret; pdev = cpufreq_get_driver_data(); priv = platform_get_drvdata(pdev); policy->driver_data = priv; dev = &pdev->dev; freq_table = brcm_avs_get_freq_table(dev, priv); if (IS_ERR(freq_table)) { ret = PTR_ERR(freq_table); dev_err(dev, "Couldn't determine frequency table (%d).\n", ret); return ret; } policy->freq_table = freq_table; /* All cores share the same clock and thus the same policy. */ cpumask_setall(policy->cpus); ret = __issue_avs_command(priv, AVS_CMD_ENABLE, false, NULL); if (!ret) { unsigned int pstate; ret = brcm_avs_get_pstate(priv, &pstate); if (!ret) { policy->cur = freq_table[pstate].frequency; dev_info(dev, "registered\n"); return 0; } } dev_err(dev, "couldn't initialize driver (%d)\n", ret); return ret; } static ssize_t show_brcm_avs_pstate(struct cpufreq_policy *policy, char *buf) { struct private_data *priv = policy->driver_data; unsigned int pstate; if (brcm_avs_get_pstate(priv, &pstate)) return sprintf(buf, "<unknown>\n"); return sprintf(buf, "%u\n", pstate); } static ssize_t show_brcm_avs_mode(struct cpufreq_policy *policy, char *buf) { struct private_data *priv = policy->driver_data; struct pmap pmap; if (brcm_avs_get_pmap(priv, &pmap)) return sprintf(buf, "<unknown>\n"); return sprintf(buf, "%s %u\n", brcm_avs_mode_to_string(pmap.mode), pmap.mode); } static ssize_t show_brcm_avs_pmap(struct cpufreq_policy *policy, char *buf) { unsigned int mdiv_p0, mdiv_p1, mdiv_p2, mdiv_p3, mdiv_p4; struct private_data *priv = policy->driver_data; unsigned int ndiv, pdiv; struct pmap pmap; if (brcm_avs_get_pmap(priv, &pmap)) return sprintf(buf, "<unknown>\n"); brcm_avs_parse_p1(pmap.p1, &mdiv_p0, &pdiv, &ndiv); brcm_avs_parse_p2(pmap.p2, &mdiv_p1, &mdiv_p2, &mdiv_p3, &mdiv_p4); return sprintf(buf, "0x%08x 0x%08x %u %u %u %u %u %u %u %u %u\n", pmap.p1, pmap.p2, ndiv, pdiv, mdiv_p0, mdiv_p1, mdiv_p2, mdiv_p3, mdiv_p4, pmap.mode, pmap.state); } static ssize_t show_brcm_avs_voltage(struct cpufreq_policy *policy, char *buf) { struct private_data *priv = policy->driver_data; return sprintf(buf, "0x%08lx\n", brcm_avs_get_voltage(priv->base)); } static ssize_t show_brcm_avs_frequency(struct cpufreq_policy *policy, char *buf) { struct private_data *priv = policy->driver_data; return sprintf(buf, "0x%08lx\n", brcm_avs_get_frequency(priv->base)); } cpufreq_freq_attr_ro(brcm_avs_pstate); cpufreq_freq_attr_ro(brcm_avs_mode); cpufreq_freq_attr_ro(brcm_avs_pmap); cpufreq_freq_attr_ro(brcm_avs_voltage); cpufreq_freq_attr_ro(brcm_avs_frequency); static struct freq_attr *brcm_avs_cpufreq_attr[] = { &cpufreq_freq_attr_scaling_available_freqs, &brcm_avs_pstate, &brcm_avs_mode, &brcm_avs_pmap, &brcm_avs_voltage, &brcm_avs_frequency, NULL }; static struct cpufreq_driver brcm_avs_driver = { .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = brcm_avs_target_index, .get = brcm_avs_cpufreq_get, .suspend = brcm_avs_suspend, .resume = brcm_avs_resume, .init = brcm_avs_cpufreq_init, .attr = brcm_avs_cpufreq_attr, .name = BRCM_AVS_CPUFREQ_PREFIX, }; static int brcm_avs_cpufreq_probe(struct platform_device *pdev) { int ret; ret = brcm_avs_prepare_init(pdev); if (ret) return ret; brcm_avs_driver.driver_data = pdev; return cpufreq_register_driver(&brcm_avs_driver); } static int brcm_avs_cpufreq_remove(struct platform_device *pdev) { struct private_data *priv; int ret; ret = cpufreq_unregister_driver(&brcm_avs_driver); if (ret) return ret; priv = platform_get_drvdata(pdev); iounmap(priv->base); iounmap(priv->avs_intr_base); return 0; } static const struct of_device_id brcm_avs_cpufreq_match[] = { { .compatible = BRCM_AVS_CPU_DATA }, { } }; MODULE_DEVICE_TABLE(of, brcm_avs_cpufreq_match); static struct platform_driver brcm_avs_cpufreq_platdrv = { .driver = { .name = BRCM_AVS_CPUFREQ_NAME, .of_match_table = brcm_avs_cpufreq_match, }, .probe = brcm_avs_cpufreq_probe, .remove = brcm_avs_cpufreq_remove, }; module_platform_driver(brcm_avs_cpufreq_platdrv); MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>"); MODULE_DESCRIPTION("CPUfreq driver for Broadcom STB AVS"); MODULE_LICENSE("GPL");
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