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SubjectRe: [PATCH V2 04/12] clk: tegra: add support for peripheral clock suspend and resume
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On 5/29/19 4:30 PM, Stephen Boyd wrote:
> Quoting Sowjanya Komatineni (2019-05-28 16:08:48)
>> This patch implements peripheral clock context save and restore
>> to support system suspend and resume operation.
> Again, why?
Will add more in commit in next version of this series.
>> diff --git a/drivers/clk/tegra/clk.c b/drivers/clk/tegra/clk.c
>> index 6f2862eddad7..08b788766564 100644
>> --- a/drivers/clk/tegra/clk.c
>> +++ b/drivers/clk/tegra/clk.c
>> @@ -81,6 +81,10 @@ static struct clk **clks;
>> static int clk_num;
>> static struct clk_onecell_data clk_data;
>>
>> +#ifdef CONFIG_PM_SLEEP
>> +static u32 *periph_ctx;
>> +#endif
> Please move this into the ifdef below.
>
WIll fix in V3
>> +
>> /* Handlers for SoC-specific reset lines */
>> static int (*special_reset_assert)(unsigned long);
>> static int (*special_reset_deassert)(unsigned long);
>> @@ -210,6 +214,65 @@ const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
>> }
>> }
>>
>> +#ifdef CONFIG_PM_SLEEP
>> +void tegra_clk_periph_suspend(void __iomem *clk_base)
>> +{
>> + int i, idx;
>> +
>> + idx = 0;
>> + for (i = 0; i < periph_banks; i++, idx++)
>> + periph_ctx[idx] =
>> + readl_relaxed(clk_base + periph_regs[i].rst_reg);
>> +
>> + for (i = 0; i < periph_banks; i++, idx++)
>> + periph_ctx[idx] =
>> + readl_relaxed(clk_base + periph_regs[i].enb_reg);
>> +}
>> +
>> +void tegra_clk_periph_force_on(u32 *clks_on, int count, void __iomem *clk_base)
>> +{
>> + int i;
>> +
>> + WARN_ON(count != periph_banks);
>> +
>> + for (i = 0; i < count; i++)
>> + writel_relaxed(clks_on[i], clk_base + periph_regs[i].enb_reg);
>> +}
>> +
>> +void tegra_clk_periph_resume(void __iomem *clk_base)
>> +{
>> + int i, idx;
>> +
>> + idx = 0;
>> + for (i = 0; i < periph_banks; i++, idx++)
>> + writel_relaxed(periph_ctx[idx],
>> + clk_base + periph_regs[i].rst_reg);
>> +
>> + /* ensure all resets have propagated */
>> + fence_udelay(2, clk_base);
>> + tegra_read_chipid();
>> +
>> + for (i = 0; i < periph_banks; i++, idx++)
>> + writel_relaxed(periph_ctx[idx],
>> + clk_base + periph_regs[i].enb_reg);
>> +
>> + /* ensure all enables have propagated */
>> + fence_udelay(2, clk_base);
>> + tegra_read_chipid();
>> +}
>> +
>> +static int tegra_clk_suspend_ctx_init(int banks)
>> +{
>> + int err = 0;
>> +
>> + periph_ctx = kzalloc(2 * banks * sizeof(*periph_ctx), GFP_KERNEL);
> Is this kcalloc(2 * banks, sizeof(*periph_ctx)... ?
Will fix in V3
>> + if (!periph_ctx)
>> + err = -ENOMEM;
>> +
>> + return err;
>> +}
>> +#endif
>> +
>> struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
>> {
>> clk_base = regs;
>> @@ -226,11 +289,20 @@ struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
>> periph_banks = banks;
>>
>> clks = kcalloc(num, sizeof(struct clk *), GFP_KERNEL);
>> - if (!clks)
>> + if (!clks) {
>> kfree(periph_clk_enb_refcnt);
>> + return NULL;
>> + }
>>
>> clk_num = num;
>>
>> +#ifdef CONFIG_PM_SLEEP
> Can you use if (IS_ENABLED(CONFIG_PM_SLEEP)) here?
Will fix in V3
>
>> + if (tegra_clk_suspend_ctx_init(banks)) {
>> + kfree(periph_clk_enb_refcnt);
>> + kfree(clks);
>> + return NULL;
>> + }
>> +#endif
>> return clks;
>> }
>>

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