On Mon, 8 Jan 2024, Hans de Goede wrote:
> From: Johannes Stezenbach <js@xxxxxxxxx>
>
> For the Bay Trail or Cherry Trail SoC to enter the S0i3 power-level
> at s2idle suspend requires most of the hw-blocks / devices in the SoC
> to be in D3 when entering s2idle suspend.
>
> If some devices are not in D3 then the SoC will stay in a higher
> power state, consuming much more power from the battery then in S0i3.
>
> Use the new acpi_s2idle_dev_ops and acpi_register_lps0_dev()
> functionality to register a new s2idle check function which checks that
> all hardware blocks in the South complex (controlled by the PMC)
> are in a state that allows the SoC to enter S0i3 and prints an error
> message for any device in D0.
>
> Some blocks are not used on lower-featured versions of the SoC and
> these blocks will always report being in D0 on SoCs were they are
> not used. A false-positive mask is used to identify these blocks
> and for blocks in this mask the error is turned into a debug message
> to avoid false-positive error messages.
>
> Note the pmc_atom code is enabled by CONFIG_X86_INTEL_LPSS which
> already depends on ACPI.
>
> Signed-off-by: Johannes Stezenbach <js@xxxxxxxxx>
> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
> [hdegoede: Use acpi_s2idle_dev_ops, ignore fused off blocks, PMIC I2C]
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> Changes in v3:
> - Reword commit message
> - Drop confusing /* Low Part */ and /* High Part */ comments
>
> Changes in v2:
> - Drop duplicated "pmc_atom: " prefix from pr_err() / pr_dbg() messages
> ---
> drivers/platform/x86/pmc_atom.c | 64 +++++++++++++++++++++++++++++++++
> 1 file changed, 64 insertions(+)
>
> diff --git a/drivers/platform/x86/pmc_atom.c b/drivers/platform/x86/pmc_atom.c
> index 93a6414c6611..ec60b734b9cb 100644
> --- a/drivers/platform/x86/pmc_atom.c
> +++ b/drivers/platform/x86/pmc_atom.c
> @@ -6,6 +6,7 @@
>
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +#include <linux/acpi.h>
> #include <linux/debugfs.h>
> #include <linux/device.h>
> #include <linux/dmi.h>
> @@ -17,6 +18,7 @@
> #include <linux/platform_device.h>
> #include <linux/pci.h>
> #include <linux/seq_file.h>
> +#include <linux/suspend.h>
>
> struct pmc_bit_map {
> const char *name;
> @@ -448,6 +450,64 @@ static int pmc_setup_clks(struct pci_dev *pdev, void __iomem *pmc_regmap,
> return 0;
> }
>
> +#ifdef CONFIG_SUSPEND
> +static void pmc_dev_state_check(u32 sts, const struct pmc_bit_map *sts_map,
> + u32 fd, const struct pmc_bit_map *fd_map,
> + u32 sts_possible_false_pos)
> +{
> + int index;
> +
> + for (index = 0; sts_map[index].name; index++) {
> + if (!(fd_map[index].bit_mask & fd) &&
> + !(sts_map[index].bit_mask & sts)) {
> + if (sts_map[index].bit_mask & sts_possible_false_pos)
> + pm_pr_dbg("%s is in D0 prior to s2idle\n",
> + sts_map[index].name);
> + else
> + pr_err("%s is in D0 prior to s2idle\n",
> + sts_map[index].name);
> + }
> + }
> +}
> +
> +static void pmc_s2idle_check(void)
> +{
> + struct pmc_dev *pmc = &pmc_device;
> + const struct pmc_reg_map *m = pmc->map;
> + u32 func_dis, func_dis_2;
> + u32 d3_sts_0, d3_sts_1;
> + u32 false_pos_sts_0, false_pos_sts_1;
> +
> + func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
> + func_dis_2 = pmc_reg_read(pmc, PMC_FUNC_DIS_2);
> + d3_sts_0 = pmc_reg_read(pmc, PMC_D3_STS_0);
> + d3_sts_1 = pmc_reg_read(pmc, PMC_D3_STS_1);
> +
> + /*
> + * Some blocks are not used on lower-featured versions of the SoC and
> + * always report D0, add these to false_pos mask to log at debug level.
> + */
> + if (m->d3_sts_1 == byt_d3_sts_1_map) {
> + /* Bay Trail */
> + false_pos_sts_0 = BIT_GBE | BIT_SATA | BIT_PCIE_PORT0 |
> + BIT_PCIE_PORT1 | BIT_PCIE_PORT2 | BIT_PCIE_PORT3 |
> + BIT_LPSS2_F5_I2C5;
> + false_pos_sts_1 = BIT_SMB | BIT_USH_SS_PHY | BIT_DFX;
> + } else {
> + /* Cherry Trail */
> + false_pos_sts_0 = BIT_GBE | BIT_SATA | BIT_LPSS2_F7_I2C7;
> + false_pos_sts_1 = BIT_SMB | BIT_STS_ISH;
> + }
> +
> + pmc_dev_state_check(d3_sts_0, m->d3_sts_0, func_dis, m->func_dis, false_pos_sts_0);
> + pmc_dev_state_check(d3_sts_1, m->d3_sts_1, func_dis_2, m->func_dis_2, false_pos_sts_1);
> +}
> +
> +static struct acpi_s2idle_dev_ops pmc_s2idle_ops = {
> + .check = pmc_s2idle_check,
> +};
> +#endif
> +
> static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
> {
> struct pmc_dev *pmc = &pmc_device;
> @@ -485,6 +545,10 @@ static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
> dev_warn(&pdev->dev, "platform clocks register failed: %d\n",
> ret);
>
> +#ifdef CONFIG_SUSPEND
> + acpi_register_lps0_dev(&pmc_s2idle_ops);
> +#endif
I'm sorry I missed this in v2, this could have also used #else +
dummy function.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
--
i.
