diff options
Diffstat (limited to 'drivers/soc')
| -rw-r--r-- | drivers/soc/tegra/pmc.c | 74 |
1 files changed, 59 insertions, 15 deletions
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c index c9b1baae5d8a..1f78e8497fde 100644 --- a/drivers/soc/tegra/pmc.c +++ b/drivers/soc/tegra/pmc.c @@ -324,6 +324,7 @@ static const char * const tegra210_reset_sources[] = { * @pctl_dev: pin controller exposed by the PMC * @domain: IRQ domain provided by the PMC * @irq: chip implementation for the IRQ domain + * @clk_nb: pclk clock changes handler */ struct tegra_pmc { struct device *dev; @@ -359,6 +360,8 @@ struct tegra_pmc { struct irq_domain *domain; struct irq_chip irq; + + struct notifier_block clk_nb; }; static struct tegra_pmc *pmc = &(struct tegra_pmc) { @@ -1207,7 +1210,7 @@ static int tegra_io_pad_prepare(struct tegra_pmc *pmc, enum tegra_io_pad id, return err; if (pmc->clk) { - rate = clk_get_rate(pmc->clk); + rate = pmc->rate; if (!rate) { dev_err(pmc->dev, "failed to get clock rate\n"); return -ENODEV; @@ -1448,6 +1451,7 @@ void tegra_pmc_set_suspend_mode(enum tegra_suspend_mode mode) void tegra_pmc_enter_suspend_mode(enum tegra_suspend_mode mode) { unsigned long long rate = 0; + u64 ticks; u32 value; switch (mode) { @@ -1456,7 +1460,7 @@ void tegra_pmc_enter_suspend_mode(enum tegra_suspend_mode mode) break; case TEGRA_SUSPEND_LP2: - rate = clk_get_rate(pmc->clk); + rate = pmc->rate; break; default: @@ -1466,21 +1470,15 @@ void tegra_pmc_enter_suspend_mode(enum tegra_suspend_mode mode) if (WARN_ON_ONCE(rate == 0)) rate = 100000000; - if (rate != pmc->rate) { - u64 ticks; - - ticks = pmc->cpu_good_time * rate + USEC_PER_SEC - 1; - do_div(ticks, USEC_PER_SEC); - tegra_pmc_writel(pmc, ticks, PMC_CPUPWRGOOD_TIMER); + ticks = pmc->cpu_good_time * rate + USEC_PER_SEC - 1; + do_div(ticks, USEC_PER_SEC); + tegra_pmc_writel(pmc, ticks, PMC_CPUPWRGOOD_TIMER); - ticks = pmc->cpu_off_time * rate + USEC_PER_SEC - 1; - do_div(ticks, USEC_PER_SEC); - tegra_pmc_writel(pmc, ticks, PMC_CPUPWROFF_TIMER); + ticks = pmc->cpu_off_time * rate + USEC_PER_SEC - 1; + do_div(ticks, USEC_PER_SEC); + tegra_pmc_writel(pmc, ticks, PMC_CPUPWROFF_TIMER); - wmb(); - - pmc->rate = rate; - } + wmb(); value = tegra_pmc_readl(pmc, PMC_CNTRL); value &= ~PMC_CNTRL_SIDE_EFFECT_LP0; @@ -2140,6 +2138,33 @@ static int tegra_pmc_irq_init(struct tegra_pmc *pmc) return 0; } +static int tegra_pmc_clk_notify_cb(struct notifier_block *nb, + unsigned long action, void *ptr) +{ + struct tegra_pmc *pmc = container_of(nb, struct tegra_pmc, clk_nb); + struct clk_notifier_data *data = ptr; + + switch (action) { + case PRE_RATE_CHANGE: + mutex_lock(&pmc->powergates_lock); + break; + + case POST_RATE_CHANGE: + pmc->rate = data->new_rate; + /* fall through */ + + case ABORT_RATE_CHANGE: + mutex_unlock(&pmc->powergates_lock); + break; + + default: + WARN_ON_ONCE(1); + return notifier_from_errno(-EINVAL); + } + + return NOTIFY_OK; +} + static int tegra_pmc_probe(struct platform_device *pdev) { void __iomem *base; @@ -2203,6 +2228,23 @@ static int tegra_pmc_probe(struct platform_device *pdev) pmc->clk = NULL; } + /* + * PCLK clock rate can't be retrieved using CLK API because it + * causes lockup if CPU enters LP2 idle state from some other + * CLK notifier, hence we're caching the rate's value locally. + */ + if (pmc->clk) { + pmc->clk_nb.notifier_call = tegra_pmc_clk_notify_cb; + err = clk_notifier_register(pmc->clk, &pmc->clk_nb); + if (err) { + dev_err(&pdev->dev, + "failed to register clk notifier\n"); + return err; + } + + pmc->rate = clk_get_rate(pmc->clk); + } + pmc->dev = &pdev->dev; tegra_pmc_init(pmc); @@ -2254,6 +2296,8 @@ cleanup_debugfs: cleanup_sysfs: device_remove_file(&pdev->dev, &dev_attr_reset_reason); device_remove_file(&pdev->dev, &dev_attr_reset_level); + clk_notifier_unregister(pmc->clk, &pmc->clk_nb); + return err; } |