cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

xen_drm_front_cfg.c (1854B)

      1// SPDX-License-Identifier: GPL-2.0 OR MIT
      2
      3/*
      4 *  Xen para-virtual DRM device
      5 *
      6 * Copyright (C) 2016-2018 EPAM Systems Inc.
      7 *
      8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
      9 */
     10
     11#include <linux/device.h>
     12
     13#include <drm/drm_print.h>
     14
     15#include <xen/interface/io/displif.h>
     16#include <xen/xenbus.h>
     17
     18#include "xen_drm_front.h"
     19#include "xen_drm_front_cfg.h"
     20
     21static int cfg_connector(struct xen_drm_front_info *front_info,
     22			 struct xen_drm_front_cfg_connector *connector,
     23			 const char *path, int index)
     24{
     25	char *connector_path;
     26
     27	connector_path = devm_kasprintf(&front_info->xb_dev->dev,
     28					GFP_KERNEL, "%s/%d", path, index);
     29	if (!connector_path)
     30		return -ENOMEM;
     31
     32	if (xenbus_scanf(XBT_NIL, connector_path, XENDISPL_FIELD_RESOLUTION,
     33			 "%d" XENDISPL_RESOLUTION_SEPARATOR "%d",
     34			 &connector->width, &connector->height) < 0) {
     35		/* either no entry configured or wrong resolution set */
     36		connector->width = 0;
     37		connector->height = 0;
     38		return -EINVAL;
     39	}
     40
     41	connector->xenstore_path = connector_path;
     42
     43	DRM_INFO("Connector %s: resolution %dx%d\n",
     44		 connector_path, connector->width, connector->height);
     45	return 0;
     46}
     47
     48int xen_drm_front_cfg_card(struct xen_drm_front_info *front_info,
     49			   struct xen_drm_front_cfg *cfg)
     50{
     51	struct xenbus_device *xb_dev = front_info->xb_dev;
     52	int ret, i;
     53
     54	if (xenbus_read_unsigned(front_info->xb_dev->nodename,
     55				 XENDISPL_FIELD_BE_ALLOC, 0)) {
     56		DRM_INFO("Backend can provide display buffers\n");
     57		cfg->be_alloc = true;
     58	}
     59
     60	cfg->num_connectors = 0;
     61	for (i = 0; i < ARRAY_SIZE(cfg->connectors); i++) {
     62		ret = cfg_connector(front_info, &cfg->connectors[i],
     63				    xb_dev->nodename, i);
     64		if (ret < 0)
     65			break;
     66		cfg->num_connectors++;
     67	}
     68
     69	if (!cfg->num_connectors) {
     70		DRM_ERROR("No connector(s) configured at %s\n",
     71			  xb_dev->nodename);
     72		return -ENODEV;
     73	}
     74
     75	return 0;
     76}
     77