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-rw-r--r--MAINTAINERS1
-rw-r--r--drivers/cpufreq/Kconfig.arm11
-rw-r--r--drivers/cpufreq/Makefile1
-rw-r--r--drivers/cpufreq/brcmstb-avs-cpufreq.c736
4 files changed, 749 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 9379aca4bec4..d0ca1198d8ab 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2744,6 +2744,7 @@ M: bcm-kernel-feedback-list@broadcom.com
L: linux-pm@vger.kernel.org
S: Maintained
F: Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt
+F: drivers/cpufreq/brcmstb*
BROADCOM SPECIFIC AMBA DRIVER (BCMA)
M: Rafał Miłecki <zajec5@gmail.com>
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index fdbc630272b3..04f7862eacd3 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -12,6 +12,17 @@ config ARM_BIG_LITTLE_CPUFREQ
help
This enables the Generic CPUfreq driver for ARM big.LITTLE platforms.
+config ARM_BRCMSTB_AVS_CPUFREQ
+ tristate "Broadcom STB AVS CPUfreq driver"
+ depends on ARCH_BRCMSTB || COMPILE_TEST
+ default y
+ help
+ Some Broadcom STB SoCs use a co-processor running proprietary firmware
+ ("AVS") to handle voltage and frequency scaling. This driver provides
+ a standard CPUfreq interface to to the firmware.
+
+ Say Y, if you have a Broadcom SoC with AVS support for DFS or DVFS.
+
config ARM_DT_BL_CPUFREQ
tristate "Generic probing via DT for ARM big LITTLE CPUfreq driver"
depends on ARM_BIG_LITTLE_CPUFREQ && OF
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 7dde82179d62..1e46c3918e7a 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_ARM_BIG_LITTLE_CPUFREQ) += arm_big_little.o
# LITTLE drivers, so that it is probed last.
obj-$(CONFIG_ARM_DT_BL_CPUFREQ) += arm_big_little_dt.o
+obj-$(CONFIG_ARM_BRCMSTB_AVS_CPUFREQ) += brcmstb-avs-cpufreq.o
obj-$(CONFIG_ARCH_DAVINCI) += davinci-cpufreq.o
obj-$(CONFIG_UX500_SOC_DB8500) += dbx500-cpufreq.o
obj-$(CONFIG_ARM_EXYNOS5440_CPUFREQ) += exynos5440-cpufreq.o
diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c
new file mode 100644
index 000000000000..4415fa051283
--- /dev/null
+++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c
@@ -0,0 +1,736 @@
+/*
+ * 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_kzalloc(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;
+
+ return brcm_avs_get_pmap(priv, &priv->pmap);
+}
+
+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);
+ platform_set_drvdata(pdev, NULL);
+
+ 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;
+ }
+
+ ret = cpufreq_table_validate_and_show(policy, freq_table);
+ if (ret) {
+ dev_err(dev, "invalid frequency table: %d\n", ret);
+ return ret;
+ }
+
+ /* 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\n",
+ pmap.p1, pmap.p2, ndiv, pdiv, mdiv_p0, mdiv_p1, mdiv_p2,
+ mdiv_p3, mdiv_p4);
+}
+
+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);
+
+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);
+ platform_set_drvdata(pdev, NULL);
+
+ 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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