[alsa-devel] [PATCH v2 2/2] ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller
Takashi Iwai
tiwai at suse.de
Thu Jul 3 08:31:08 CEST 2014
At Thu, 3 Jul 2014 13:02:04 +0800,
mengdong.lin at intel.com wrote:
>
> From: Mengdong Lin <mengdong.lin at 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 at 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
>
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