Commit fcb0c4b0 authored by Sahitya Tummala's avatar Sahitya Tummala Committed by Martin K. Petersen

scsi: ufs: Add sysfs node to dynamically control clock scaling

Provide an option to enable/disable clock scaling during runtime.
Write 1/0 to "clkscale_enable" sysfs node to enable/disable clock
scaling.
Signed-off-by: default avatarSahitya Tummala <stummala@codeaurora.org>
Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent b427411a
......@@ -230,6 +230,9 @@ static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba);
static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba);
static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
static void ufshcd_resume_clkscaling(struct ufs_hba *hba);
static void ufshcd_suspend_clkscaling(struct ufs_hba *hba);
static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up);
static irqreturn_t ufshcd_intr(int irq, void *__hba);
static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
struct ufs_pa_layer_attr *desired_pwr_mode);
......@@ -713,16 +716,58 @@ static bool ufshcd_is_unipro_pa_params_tuning_req(struct ufs_hba *hba)
static void ufshcd_suspend_clkscaling(struct ufs_hba *hba)
{
if (ufshcd_is_clkscaling_enabled(hba)) {
devfreq_suspend_device(hba->devfreq);
hba->clk_scaling.window_start_t = 0;
}
if (!ufshcd_is_clkscaling_supported(hba))
return;
devfreq_suspend_device(hba->devfreq);
hba->clk_scaling.window_start_t = 0;
}
static void ufshcd_resume_clkscaling(struct ufs_hba *hba)
{
if (ufshcd_is_clkscaling_enabled(hba))
devfreq_resume_device(hba->devfreq);
devfreq_resume_device(hba->devfreq);
}
static ssize_t ufshcd_clkscale_enable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ufs_hba *hba = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%d\n", hba->clk_scaling.is_allowed);
}
static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct ufs_hba *hba = dev_get_drvdata(dev);
u32 value;
int err;
if (kstrtou32(buf, 0, &value))
return -EINVAL;
value = !!value;
if (value == hba->clk_scaling.is_allowed)
goto out;
pm_runtime_get_sync(hba->dev);
ufshcd_hold(hba, false);
if (value) {
ufshcd_resume_clkscaling(hba);
} else {
ufshcd_suspend_clkscaling(hba);
err = ufshcd_scale_clks(hba, true);
if (err)
dev_err(hba->dev, "%s: failed to scale clocks up %d\n",
__func__, err);
}
hba->clk_scaling.is_allowed = value;
ufshcd_release(hba);
pm_runtime_put_sync(hba->dev);
out:
return count;
}
static void ufshcd_ungate_work(struct work_struct *work)
......@@ -758,7 +803,8 @@ static void ufshcd_ungate_work(struct work_struct *work)
hba->clk_gating.is_suspended = false;
}
unblock_reqs:
ufshcd_resume_clkscaling(hba);
if (hba->clk_scaling.is_allowed)
ufshcd_resume_clkscaling(hba);
scsi_unblock_requests(hba->host);
}
......@@ -1046,7 +1092,7 @@ static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
/* Must be called with host lock acquired */
static void ufshcd_clk_scaling_start_busy(struct ufs_hba *hba)
{
if (!ufshcd_is_clkscaling_enabled(hba))
if (!ufshcd_is_clkscaling_supported(hba))
return;
if (!hba->clk_scaling.is_busy_started) {
......@@ -1059,7 +1105,7 @@ static void ufshcd_clk_scaling_update_busy(struct ufs_hba *hba)
{
struct ufs_clk_scaling *scaling = &hba->clk_scaling;
if (!ufshcd_is_clkscaling_enabled(hba))
if (!ufshcd_is_clkscaling_supported(hba))
return;
if (!hba->outstanding_reqs && scaling->is_busy_started) {
......@@ -5526,12 +5572,15 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
pm_runtime_put_sync(hba->dev);
}
/* Resume devfreq after UFS device is detected */
if (ufshcd_is_clkscaling_supported(hba)) {
ufshcd_resume_clkscaling(hba);
hba->clk_scaling.is_allowed = true;
}
if (!hba->is_init_prefetch)
hba->is_init_prefetch = true;
/* Resume devfreq after UFS device is detected */
ufshcd_resume_clkscaling(hba);
out:
/*
* If we failed to initialize the device or the device is not
......@@ -6484,7 +6533,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
ufshcd_urgent_bkops(hba);
hba->clk_gating.is_suspended = false;
ufshcd_resume_clkscaling(hba);
if (hba->clk_scaling.is_allowed)
ufshcd_resume_clkscaling(hba);
/* Schedule clock gating in case of no access to UFS device yet */
ufshcd_release(hba);
......@@ -6702,6 +6752,8 @@ void ufshcd_remove(struct ufs_hba *hba)
ufshcd_hba_stop(hba, true);
ufshcd_exit_clk_gating(hba);
if (ufshcd_is_clkscaling_supported(hba))
device_remove_file(hba->dev, &hba->clk_scaling.enable_attr);
ufshcd_hba_exit(hba);
}
EXPORT_SYMBOL_GPL(ufshcd_remove);
......@@ -6835,7 +6887,7 @@ static int ufshcd_devfreq_target(struct device *dev,
bool release_clk_hold = false;
unsigned long irq_flags;
if (!ufshcd_is_clkscaling_enabled(hba))
if (!ufshcd_is_clkscaling_supported(hba))
return -EINVAL;
spin_lock_irqsave(hba->host->host_lock, irq_flags);
......@@ -6883,7 +6935,7 @@ static int ufshcd_devfreq_get_dev_status(struct device *dev,
struct ufs_clk_scaling *scaling = &hba->clk_scaling;
unsigned long flags;
if (!ufshcd_is_clkscaling_enabled(hba))
if (!ufshcd_is_clkscaling_supported(hba))
return -EINVAL;
memset(stat, 0, sizeof(*stat));
......@@ -6919,6 +6971,16 @@ static struct devfreq_dev_profile ufs_devfreq_profile = {
.target = ufshcd_devfreq_target,
.get_dev_status = ufshcd_devfreq_get_dev_status,
};
static void ufshcd_clkscaling_init_sysfs(struct ufs_hba *hba)
{
hba->clk_scaling.enable_attr.show = ufshcd_clkscale_enable_show;
hba->clk_scaling.enable_attr.store = ufshcd_clkscale_enable_store;
sysfs_attr_init(&hba->clk_scaling.enable_attr.attr);
hba->clk_scaling.enable_attr.attr.name = "clkscale_enable";
hba->clk_scaling.enable_attr.attr.mode = 0644;
if (device_create_file(hba->dev, &hba->clk_scaling.enable_attr))
dev_err(hba->dev, "Failed to create sysfs for clkscale_enable\n");
}
/**
* ufshcd_init - Driver initialization routine
......@@ -7045,7 +7107,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
goto out_remove_scsi_host;
}
if (ufshcd_is_clkscaling_enabled(hba)) {
if (ufshcd_is_clkscaling_supported(hba)) {
hba->devfreq = devm_devfreq_add_device(dev, &ufs_devfreq_profile,
"simple_ondemand", NULL);
if (IS_ERR(hba->devfreq)) {
......@@ -7056,6 +7118,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
}
/* Suspend devfreq until the UFS device is detected */
ufshcd_suspend_clkscaling(hba);
ufshcd_clkscaling_init_sysfs(hba);
}
/* Hold auto suspend until async scan completes */
......
......@@ -342,6 +342,8 @@ struct ufs_clk_scaling {
bool is_busy_started;
unsigned long tot_busy_t;
unsigned long window_start_t;
struct device_attribute enable_attr;
bool is_allowed;
};
/**
......@@ -580,7 +582,7 @@ static inline bool ufshcd_can_hibern8_during_gating(struct ufs_hba *hba)
{
return hba->caps & UFSHCD_CAP_HIBERN8_WITH_CLK_GATING;
}
static inline int ufshcd_is_clkscaling_enabled(struct ufs_hba *hba)
static inline int ufshcd_is_clkscaling_supported(struct ufs_hba *hba)
{
return hba->caps & UFSHCD_CAP_CLK_SCALING;
}
......
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