[Intel-gfx] [PATCH 1/1] drm/i915: Export LMEM max memory bandwidth via sysfs

[Gupta, Anshuman]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of
> Himal Prasad Ghimiray
> Sent: Monday, November 21, 2022 3:32 PM
> To: intel-gfx at lists.freedesktop.org
> Subject: [Intel-gfx] [PATCH 1/1] drm/i915: Export LMEM max memory
> bandwidth via sysfs
> 
> Export lmem maximum memory bandwidth to the userspace via sysfs
> 
> (v2)
> Add TODO comment to have client parts specific condition (Anshuman)
> Remove prelim prefix from the sysfs node name (Aravind)
> 
> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_reg.h   |  2 ++
>  drivers/gpu/drm/i915/i915_sysfs.c | 28 ++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h
> b/drivers/gpu/drm/i915/i915_reg.h index 8e1892d147741..1d59b84b86ad2
> 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -6606,6 +6606,8 @@
>  #define	    POWER_SETUP_I1_WATTS		REG_BIT(31)
>  #define	    POWER_SETUP_I1_SHIFT		6	/* 10.6 fixed
> point format */
>  #define	    POWER_SETUP_I1_DATA_MASK
> 	REG_GENMASK(15, 0)
> +#define	  PCODE_MEMORY_CONFIG			0x70
Please use DG1_ prefix as this mbox started from DG1 onwards.
 And  please try to follow the ascending order for commands attest for the new command we are adding.
> +#define
> MEMORY_CONFIG_SUBCOMMAND_READ_MAX_BANDWIDTH 0x0
Here as well use DG1_ prefix.
>  #define GEN12_PCODE_READ_SAGV_BLOCK_TIME_US	0x23
>  #define   XEHP_PCODE_FREQUENCY_CONFIG		0x6e	/* xehpsdv,
> pvc */
>  /* XEHP_PCODE_FREQUENCY_CONFIG sub-commands (param1) */ diff --git
> a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c
> index 595e8b5749907..69df2012bd10e 100644
> --- a/drivers/gpu/drm/i915/i915_sysfs.c
> +++ b/drivers/gpu/drm/i915/i915_sysfs.c
> @@ -37,7 +37,10 @@
> 
>  #include "i915_drv.h"
>  #include "i915_sysfs.h"
> +#include "i915_reg.h"
>  #include "intel_pm.h"
> +#include "intel_pcode.h"
> +
> 
>  struct drm_i915_private *kdev_minor_to_i915(struct device *kdev)  { @@ -
> 231,11 +234,36 @@ static void i915_setup_error_capture(struct device
> *kdev) {}  static void i915_teardown_error_capture(struct device *kdev) {}
> #endif
> 
> +static ssize_t
> +lmem_max_bw_Mbps_show(struct device *dev, struct device_attribute
> +*attr, char *buff) {
> +	struct drm_i915_private *i915 = kdev_minor_to_i915(dev);
> +	u32 val;
> +	int err;
> +
> +	err = snb_pcode_read_p(&i915->uncore,
> PCODE_MEMORY_CONFIG,
> +
> MEMORY_CONFIG_SUBCOMMAND_READ_MAX_BANDWIDTH,
> +			       0x0, &val);
> +	if (err)
> +		return err;
> +
> +	return sysfs_emit(buff, "%u\n", val);
> +}
> +
> +static DEVICE_ATTR_RO(lmem_max_bw_Mbps);
> +
>  void i915_setup_sysfs(struct drm_i915_private *dev_priv)  {
>  	struct device *kdev = dev_priv->drm.primary->kdev;
>  	int ret;
> 
> +	/*TODO: Need to add client Parts condition check. */
Nit use space after '/*'
/* TODO: Need to add client parts specific conditional check */ would be good.
BR,
Anshuman Gupta.

> +	if (IS_DG1(dev_priv) || IS_DG2(dev_priv)) {
> +		ret = sysfs_create_file(&kdev->kobj,
> &dev_attr_lmem_max_bw_Mbps.attr);
> +		if (ret)
> +			drm_err(&dev_priv->drm, "Setting up sysfs to read
> max B/W failed\n");
> +	}
> +
>  	if (HAS_L3_DPF(dev_priv)) {
>  		ret = device_create_bin_file(kdev, &dpf_attrs);
>  		if (ret)
> --
> 2.25.1