Re: [alsa-devel] [PATCH v2 2/2] ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller

At Thu, 3 Jul 2014 13:02:04 +0800, mengdong.lin@intel.com wrote:

From: Mengdong Lin mengdong.lin@intel.com

For HSW/BDW display HD-A controller, hda_set_bclk() is defined to set BCLK by programming the M/N values as per the core display clock (CDCLK) queried from i915 display driver.

And the audio driver will also set BCLK in azx_first_init() since the display driver can turn off the shared power in boot phase if only eDP is connected and M/N values will be lost and must be reprogrammed.

Signed-off-by: Mengdong Lin mengdong.lin@intel.com

diff --git a/sound/pci/hda/hda_i915.c b/sound/pci/hda/hda_i915.c index e9e8a4a..8b4940b 100644 --- a/sound/pci/hda/hda_i915.c +++ b/sound/pci/hda/hda_i915.c @@ -20,10 +20,20 @@ #include <linux/module.h> #include <sound/core.h> #include <drm/i915_powerwell.h> +#include "hda_priv.h" #include "hda_i915.h"

+/* Intel HSW/BDW display HDA controller Extended Mode registers.

• • EM4 (M value) and EM5 (N Value) are used to convert CDClk (Core Display
• • Clock) to 24MHz BCLK: BCLK = CDCLK * M / N
• • The values will be lost when the display power well is disabled.
• */

+#define ICH6_REG_EM4 0x100c +#define ICH6_REG_EM5 0x1010

static int (*get_power)(void); static int (*put_power)(void); +static int (*get_cdclk)(void);

int hda_display_power(bool enable) { @@ -38,6 +48,43 @@ int hda_display_power(bool enable) return put_power(); }

+void haswell_set_bclk(struct azx *chip) +{

• int cdclk_freq;
• unsigned int bclk_m, bclk_n;
• if (!get_cdclk)

• return;
  

• cdclk_freq = get_cdclk();
• switch (cdclk_freq) {
• case 337500:

• bclk_m = 16;
  

• bclk_n = 225;
  

• break;
  

• case 450000:
• default: /* default CDCLK 450MHz */

• bclk_m = 4;
  

• bclk_n = 75;
  

• break;
  

• case 540000:

• bclk_m = 4;
  

• bclk_n = 90;
  

• break;
  

• case 675000:

• bclk_m = 8;
  

• bclk_n = 225;
  

• break;
  

• }
• azx_writew(chip, EM4, bclk_m);
• azx_writew(chip, EM5, bclk_n);

+}

int hda_i915_init(void) { int err = 0; @@ -55,6 +102,10 @@ int hda_i915_init(void) return -ENODEV; }

• get_cdclk = symbol_request(i915_get_cdclk_freq);

• if (!get_cdclk) /* may have abnormal BCLK and audio playback rate */

• pr_warn("hda-i915: get_cdclk symbol get fail\n");
  

• pr_debug("HDA driver get symbol successfully from i915 module\n");

  return err;

@@ -70,6 +121,10 @@ int hda_i915_exit(void) symbol_put(i915_release_power_well); put_power = NULL; }

• if (get_cdclk) {

• symbol_put(i915_get_cdclk_freq);
  

• get_cdclk = NULL;
  

• }

  return 0;

} diff --git a/sound/pci/hda/hda_i915.h b/sound/pci/hda/hda_i915.h index bfd835f..9237340 100644 --- a/sound/pci/hda/hda_i915.h +++ b/sound/pci/hda/hda_i915.h @@ -18,6 +18,7 @@

#ifdef CONFIG_SND_HDA_I915 int hda_display_power(bool enable); +void haswell_set_bclk(struct azx *chip); int hda_i915_init(void); int hda_i915_exit(void); #else

Define a dummy function for !CONFIG_SND_HDA_I915, too. Otherwise the build will break.

I'll be off for today and pick up the revised patch later.

thanks,

Takashi

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 25753db..b6b4e71 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -62,9 +62,9 @@ #include <linux/vga_switcheroo.h> #include <linux/firmware.h> #include "hda_codec.h" -#include "hda_i915.h" #include "hda_controller.h" #include "hda_priv.h" +#include "hda_i915.h"

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; @@ -288,21 +288,8 @@ static char *driver_short_names[] = { [AZX_DRIVER_GENERIC] = "HD-Audio Generic", };

-/* Intel HSW/BDW display HDA controller Extended Mode registers.

• • EM4 (M value) and EM5 (N Value) are used to convert CDClk (Core Display
• • Clock) to 24MHz BCLK: BCLK = CDCLK * M / N
• • The values will be lost when the display power well is disabled.
• */

-#define ICH6_REG_EM4 0x100c -#define ICH6_REG_EM5 0x1010

struct hda_intel { struct azx chip;

• /* HSW/BDW display HDA controller to restore BCLK from CDCLK */
• unsigned int bclk_m;
• unsigned int bclk_n;

};

@@ -598,22 +585,6 @@ static int param_set_xint(const char *val, const struct kernel_param *kp) #define azx_del_card_list(chip) /* NOP */ #endif /* CONFIG_PM */

-static void haswell_save_bclk(struct azx *chip) -{

• struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
• hda->bclk_m = azx_readw(chip, EM4);
• hda->bclk_n = azx_readw(chip, EM5);

-}

-static void haswell_restore_bclk(struct azx *chip) -{

• struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
• azx_writew(chip, EM4, hda->bclk_m);
• azx_writew(chip, EM5, hda->bclk_n);

-}

#if defined(CONFIG_PM_SLEEP) || defined(SUPPORT_VGA_SWITCHEROO) /*

• power management

@@ -641,12 +612,6 @@ static int azx_suspend(struct device *dev) chip->irq = -1; }

• /* Save BCLK M/N values before they become invalid in D3.

• * Will test if display power well can be released now.
  

• */
  

• if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

• haswell_save_bclk(chip);
  

• if (chip->msi) pci_disable_msi(chip->pci); pci_disable_device(pci);

@@ -668,7 +633,7 @@ static int azx_resume(struct device *dev)

if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) { hda_display_power(true);

• haswell_restore_bclk(chip);
  

• haswell_set_bclk(chip);
  

  } pci_set_power_state(pci, PCI_D0); pci_restore_state(pci);

@@ -713,10 +678,9 @@ static int azx_runtime_suspend(struct device *dev) azx_stop_chip(chip); azx_enter_link_reset(chip); azx_clear_irq_pending(chip);

• if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {

• haswell_save_bclk(chip);
  

• if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) hda_display_power(false);

• }

• return 0;

}

@@ -736,7 +700,7 @@ static int azx_runtime_resume(struct device *dev)

if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) { hda_display_power(true);

• haswell_restore_bclk(chip);
  

• haswell_set_bclk(chip);
  

  }

  /* Read STATESTS before controller reset */

@@ -1426,6 +1390,10 @@ static int azx_first_init(struct azx *chip)

/* initialize chip */ azx_init_pci(chip);

• if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

• haswell_set_bclk(chip);
  

• azx_init_chip(chip, (probe_only[dev] & 2) == 0);

  /* codec detection */

-- 1.8.1.2