Re: [PATCH v2] platform/x86: amd-pmc: Export Idlemask values based on the APU

From: Shyam Sundar S K
Date: Thu Sep 16 2021 - 09:01:12 EST


+Mario

On 9/16/2021 6:10 PM, Sanket Goswami wrote:
> IdleMask is the metric used by the PM firmware to know the status of each
> of the Hardware IP blocks monitored by the PM firmware.
>
> Knowing this value is key to get the information of s2idle suspend/resume
> status. This value is mapped to PMC scratch registers, retrieve them
> accordingly based on the CPU family and the underlying firmware support.
>
> Co-developed-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
> Signed-off-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
> ---
> Changes in v2:
> - Add separate routine amd_pmc_idlemask_read to get the value.
> - Address review comments from Mario.
>
> drivers/platform/x86/amd-pmc.c | 76 ++++++++++++++++++++++++++++++++++
> 1 file changed, 76 insertions(+)
>
> diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c
> index 3481479a2942..0c970f613e09 100644
> --- a/drivers/platform/x86/amd-pmc.c
> +++ b/drivers/platform/x86/amd-pmc.c
> @@ -29,6 +29,10 @@
> #define AMD_PMC_REGISTER_RESPONSE 0x980
> #define AMD_PMC_REGISTER_ARGUMENT 0x9BC
>
> +/* PMC Scratch Registers */
> +#define AMD_PMC_SCRATCH_REG_CZN 0x94
> +#define AMD_PMC_SCRATCH_REG_YC 0xD14
> +
> /* Base address of SMU for mapping physical address to virtual address */
> #define AMD_PMC_SMU_INDEX_ADDRESS 0xB8
> #define AMD_PMC_SMU_INDEX_DATA 0xBC
> @@ -110,6 +114,10 @@ struct amd_pmc_dev {
> u32 base_addr;
> u32 cpu_id;
> u32 active_ips;
> +/* SMU version information */
> + u16 major;
> + u16 minor;
> + u16 rev;
> struct device *dev;
> struct mutex lock; /* generic mutex lock */
> #if IS_ENABLED(CONFIG_DEBUG_FS)
> @@ -201,6 +209,66 @@ static int s0ix_stats_show(struct seq_file *s, void *unused)
> }
> DEFINE_SHOW_ATTRIBUTE(s0ix_stats);
>
> +static int amd_pmc_get_smu_version(struct amd_pmc_dev *dev)
> +{
> + int rc;
> + u32 val;
> +
> + rc = amd_pmc_send_cmd(dev, 0, &val, SMU_MSG_GETSMUVERSION, 1);
> + if (rc)
> + return rc;
> +
> + dev->major = (val >> 16) & GENMASK(15, 0);
> + dev->minor = (val >> 8) & GENMASK(7, 0);
> + dev->rev = (val >> 0) & GENMASK(7, 0);
> +
> + dev_dbg(dev->dev, "SMU version is %u.%u.%u\n", dev->major, dev->minor, dev->rev);
> +
> + return 0;
> +}
> +
> +static int amd_pmc_idlemask_read(struct amd_pmc_dev *pdev, struct device *dev,
> + struct seq_file *s)
> +{
> + u32 val;
> +
> + switch (pdev->cpu_id) {
> + case AMD_CPU_ID_CZN:
> + val = amd_pmc_reg_read(pdev, AMD_PMC_SCRATCH_REG_CZN);
> + break;
> + case AMD_CPU_ID_YC:
> + val = amd_pmc_reg_read(pdev, AMD_PMC_SCRATCH_REG_YC);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (dev)
> + dev_dbg(pdev->dev, "SMU idlemask s0i3: 0x%x\n", val);
> +
> + if (s)
> + seq_printf(s, "SMU idlemask : 0x%x\n", val);
> +
> + return 0;
> +}
> +
> +static int amd_pmc_idlemask_show(struct seq_file *s, void *unused)
> +{
> + struct amd_pmc_dev *dev = s->private;
> + int rc;
> +
> + if (dev->major > 56 || (dev->major >= 55 && dev->minor >= 37)) {
> + rc = amd_pmc_idlemask_read(dev, NULL, s);
> + if (rc)
> + return rc;
> + } else {
> + seq_puts(s, "Unsupported SMU version for Idlemask\n");
> + }
> +
> + return 0;
> +}
> +DEFINE_SHOW_ATTRIBUTE(amd_pmc_idlemask);
> +
> static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
> {
> debugfs_remove_recursive(dev->dbgfs_dir);
> @@ -213,6 +281,8 @@ static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
> &smu_fw_info_fops);
> debugfs_create_file("s0ix_stats", 0644, dev->dbgfs_dir, dev,
> &s0ix_stats_fops);
> + debugfs_create_file("amd_pmc_idlemask", 0644, dev->dbgfs_dir, dev,
> + &amd_pmc_idlemask_fops);
> }
> #else
> static inline void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
> @@ -349,6 +419,8 @@ static int __maybe_unused amd_pmc_suspend(struct device *dev)
> amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_RESET, 0);
> amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_START, 0);
>
> + /* Dump the IdleMask before we send hint to SMU */
> + amd_pmc_idlemask_read(pdev, dev, NULL);
> msg = amd_pmc_get_os_hint(pdev);
> rc = amd_pmc_send_cmd(pdev, 1, NULL, msg, 0);
> if (rc)
> @@ -371,6 +443,9 @@ static int __maybe_unused amd_pmc_resume(struct device *dev)
> if (rc)
> dev_err(pdev->dev, "resume failed\n");
>
> + /* Dump the IdleMask to see the blockers */
> + amd_pmc_idlemask_read(pdev, dev, NULL);
> +
> return 0;
> }
>
> @@ -457,6 +532,7 @@ static int amd_pmc_probe(struct platform_device *pdev)
> if (err)
> dev_err(dev->dev, "SMU debugging info not supported on this platform\n");
>
> + amd_pmc_get_smu_version(dev);
> platform_set_drvdata(pdev, dev);
> amd_pmc_dbgfs_register(dev);
> return 0;
>

Looks good to me.

Acked-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>