1. 根目录:
2. sound
3. soc
4. intel
5. skylake
6. skl-nhlt.c

/*
 *  skl-nhlt.c - Intel SKL Platform NHLT parsing
 *
 *  Copyright (C) 2015 Intel Corp
 *  Author: Sanjiv Kumar <sanjiv.kumar@intel.com>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 */
#include "skl.h"

/* Unique identification for getting NHLT blobs */
static u8 OSC_UUID[16] = {0x6E, 0x88, 0x9F, 0xA6, 0xEB, 0x6C, 0x94, 0x45,
				0xA4, 0x1F, 0x7B, 0x5D, 0xCE, 0x24, 0xC5, 0x53};

#define DSDT_NHLT_PATH "\\_SB.PCI0.HDAS"

void *skl_nhlt_init(struct device *dev)
{
	acpi_handle handle;
	union acpi_object *obj;
	struct nhlt_resource_desc  *nhlt_ptr = NULL;

	if (ACPI_FAILURE(acpi_get_handle(NULL, DSDT_NHLT_PATH, &handle))) {
		dev_err(dev, "Requested NHLT device not found\n");
		return NULL;
	}

	obj = acpi_evaluate_dsm(handle, OSC_UUID, 1, 1, NULL);
	if (obj && obj->type == ACPI_TYPE_BUFFER) {
		nhlt_ptr = (struct nhlt_resource_desc  *)obj->buffer.pointer;

		return memremap(nhlt_ptr->min_addr, nhlt_ptr->length,
				MEMREMAP_WB);
	}

	dev_err(dev, "device specific method to extract NHLT blob failed\n");
	return NULL;
}

void skl_nhlt_free(void *addr)
{
	memunmap(addr);
}

static struct nhlt_specific_cfg *skl_get_specific_cfg(
		struct device *dev, struct nhlt_fmt *fmt,
		u8 no_ch, u32 rate, u16 bps)
{
	struct nhlt_specific_cfg *sp_config;
	struct wav_fmt *wfmt;
	struct nhlt_fmt_cfg *fmt_config = fmt->fmt_config;
	int i;

	dev_dbg(dev, "Format count =%d\n", fmt->fmt_count);

	for (i = 0; i < fmt->fmt_count; i++) {
		wfmt = &fmt_config->fmt_ext.fmt;
		dev_dbg(dev, "ch=%d fmt=%d s_rate=%d\n", wfmt->channels,
			 wfmt->bits_per_sample, wfmt->samples_per_sec);
		if (wfmt->channels == no_ch && wfmt->samples_per_sec == rate &&
					wfmt->bits_per_sample == bps) {
			sp_config = &fmt_config->config;

			return sp_config;
		}

		fmt_config = (struct nhlt_fmt_cfg *)(fmt_config->config.caps +
						fmt_config->config.size);
	}

	return NULL;
}

static void dump_config(struct device *dev, u32 instance_id, u8 linktype,
		u8 s_fmt, u8 num_channels, u32 s_rate, u8 dirn, u16 bps)
{
	dev_dbg(dev, "Input configuration\n");
	dev_dbg(dev, "ch=%d fmt=%d s_rate=%d\n", num_channels, s_fmt, s_rate);
	dev_dbg(dev, "vbus_id=%d link_type=%d\n", instance_id, linktype);
	dev_dbg(dev, "bits_per_sample=%d\n", bps);
}

static bool skl_check_ep_match(struct device *dev, struct nhlt_endpoint *epnt,
				u32 instance_id, u8 link_type, u8 dirn)
{
	dev_dbg(dev, "vbus_id=%d link_type=%d dir=%d\n",
		epnt->virtual_bus_id, epnt->linktype, epnt->direction);

	if ((epnt->virtual_bus_id == instance_id) &&
			(epnt->linktype == link_type) &&
			(epnt->direction == dirn))
		return true;
	else
		return false;
}

struct nhlt_specific_cfg
*skl_get_ep_blob(struct skl *skl, u32 instance, u8 link_type,
			u8 s_fmt, u8 num_ch, u32 s_rate, u8 dirn)
{
	struct nhlt_fmt *fmt;
	struct nhlt_endpoint *epnt;
	struct hdac_bus *bus = ebus_to_hbus(&skl->ebus);
	struct device *dev = bus->dev;
	struct nhlt_specific_cfg *sp_config;
	struct nhlt_acpi_table *nhlt = (struct nhlt_acpi_table *)skl->nhlt;
	u16 bps = num_ch * s_fmt;
	u8 j;

	dump_config(dev, instance, link_type, s_fmt, num_ch, s_rate, dirn, bps);

	epnt = (struct nhlt_endpoint *)nhlt->desc;

	dev_dbg(dev, "endpoint count =%d\n", nhlt->endpoint_count);

	for (j = 0; j < nhlt->endpoint_count; j++) {
		if (skl_check_ep_match(dev, epnt, instance, link_type, dirn)) {
			fmt = (struct nhlt_fmt *)(epnt->config.caps +
						 epnt->config.size);
			sp_config = skl_get_specific_cfg(dev, fmt, num_ch, s_rate, bps);
			if (sp_config)
				return sp_config;
		}

		epnt = (struct nhlt_endpoint *)((u8 *)epnt + epnt->length);
	}

	return NULL;
}