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Diffstat (limited to 'drivers/cpufreq/brcmstb-avs-cpufreq.c')
-rw-r--r--drivers/cpufreq/brcmstb-avs-cpufreq.c89
1 files changed, 59 insertions, 30 deletions
diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c
index 4f86ce2db34f..3e31e5d28b79 100644
--- a/drivers/cpufreq/brcmstb-avs-cpufreq.c
+++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c
@@ -42,6 +42,7 @@
*/
#include <linux/cpufreq.h>
+#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
@@ -178,6 +179,7 @@ struct private_data {
struct completion done;
struct semaphore sem;
struct pmap pmap;
+ int host_irq;
};
static void __iomem *__map_region(const char *name)
@@ -195,11 +197,36 @@ static void __iomem *__map_region(const char *name)
return ptr;
}
-static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send,
+static unsigned long wait_for_avs_command(struct private_data *priv,
+ unsigned long timeout)
+{
+ unsigned long time_left = 0;
+ u32 val;
+
+ /* Event driven, wait for the command interrupt */
+ if (priv->host_irq >= 0)
+ return wait_for_completion_timeout(&priv->done,
+ msecs_to_jiffies(timeout));
+
+ /* Polling for command completion */
+ do {
+ time_left = timeout;
+ val = readl(priv->base + AVS_MBOX_STATUS);
+ if (val)
+ break;
+
+ usleep_range(1000, 2000);
+ } while (--timeout);
+
+ return time_left;
+}
+
+static int __issue_avs_command(struct private_data *priv, unsigned int cmd,
+ unsigned int num_in, unsigned int num_out,
u32 args[])
{
- unsigned long time_left = msecs_to_jiffies(AVS_TIMEOUT);
void __iomem *base = priv->base;
+ unsigned long time_left;
unsigned int i;
int ret;
u32 val;
@@ -225,11 +252,9 @@ static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send,
/* 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));
- }
+ /* Provide input parameters */
+ for (i = 0; i < num_in; i++)
+ writel(args[i], base + AVS_MBOX_PARAM(i));
/* Protect from spurious interrupts. */
reinit_completion(&priv->done);
@@ -239,7 +264,7 @@ static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send,
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);
+ time_left = wait_for_avs_command(priv, AVS_TIMEOUT);
/*
* If the AVS status is not in the expected range, it means AVS didn't
@@ -256,11 +281,9 @@ static int __issue_avs_command(struct private_data *priv, int cmd, bool is_send,
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));
- }
+ /* Process returned values */
+ for (i = 0; i < num_out; 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);
@@ -338,7 +361,7 @@ 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);
+ ret = __issue_avs_command(priv, AVS_CMD_GET_PMAP, 0, 4, args);
if (ret || !pmap)
return ret;
@@ -359,7 +382,7 @@ static int brcm_avs_set_pmap(struct private_data *priv, struct pmap *pmap)
args[2] = pmap->p2;
args[3] = pmap->state;
- return __issue_avs_command(priv, AVS_CMD_SET_PMAP, true, args);
+ return __issue_avs_command(priv, AVS_CMD_SET_PMAP, 4, 0, args);
}
static int brcm_avs_get_pstate(struct private_data *priv, unsigned int *pstate)
@@ -367,7 +390,7 @@ 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);
+ ret = __issue_avs_command(priv, AVS_CMD_GET_PSTATE, 0, 1, args);
if (ret)
return ret;
*pstate = args[0];
@@ -381,7 +404,8 @@ static int brcm_avs_set_pstate(struct private_data *priv, unsigned int pstate)
args[0] = pstate;
- return __issue_avs_command(priv, AVS_CMD_SET_PSTATE, true, args);
+ return __issue_avs_command(priv, AVS_CMD_SET_PSTATE, 1, 0, args);
+
}
static u32 brcm_avs_get_voltage(void __iomem *base)
@@ -482,7 +506,14 @@ static int brcm_avs_suspend(struct cpufreq_policy *policy)
* 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);
+ ret = brcm_avs_get_pstate(priv, &priv->pmap.state);
+ if (ret)
+ return ret;
+
+ /* This is best effort. Nothing to do if it fails. */
+ (void)__issue_avs_command(priv, AVS_CMD_S2_ENTER, 0, 0, NULL);
+
+ return 0;
}
static int brcm_avs_resume(struct cpufreq_policy *policy)
@@ -490,6 +521,9 @@ static int brcm_avs_resume(struct cpufreq_policy *policy)
struct private_data *priv = policy->driver_data;
int ret;
+ /* This is best effort. Nothing to do if it fails. */
+ (void)__issue_avs_command(priv, AVS_CMD_S2_EXIT, 0, 0, NULL);
+
ret = brcm_avs_set_pmap(priv, &priv->pmap);
if (ret == -EEXIST) {
struct platform_device *pdev = cpufreq_get_driver_data();
@@ -511,7 +545,7 @@ static int brcm_avs_prepare_init(struct platform_device *pdev)
{
struct private_data *priv;
struct device *dev;
- int host_irq, ret;
+ int ret;
dev = &pdev->dev;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -538,19 +572,14 @@ static int brcm_avs_prepare_init(struct platform_device *pdev)
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;
- }
+ priv->host_irq = platform_get_irq_byname(pdev, BRCM_AVS_HOST_INTR);
- ret = devm_request_irq(dev, host_irq, irq_handler, IRQF_TRIGGER_RISING,
+ ret = devm_request_irq(dev, priv->host_irq, irq_handler,
+ IRQF_TRIGGER_RISING,
BRCM_AVS_HOST_INTR, priv);
- if (ret) {
+ if (ret && priv->host_irq >= 0) {
dev_err(dev, "IRQ request failed: %s (%d) -- %d\n",
- BRCM_AVS_HOST_INTR, host_irq, ret);
+ BRCM_AVS_HOST_INTR, priv->host_irq, ret);
goto unmap_intr_base;
}
@@ -593,7 +622,7 @@ static int brcm_avs_cpufreq_init(struct cpufreq_policy *policy)
/* 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);
+ ret = __issue_avs_command(priv, AVS_CMD_ENABLE, 0, 0, NULL);
if (!ret) {
unsigned int pstate;