coreboot-kgpe-d16/src/device/resource_allocator_common.c

61 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
#include <device/device.h>
struct pick_largest_state {
struct resource *last;
const struct device *result_dev;
struct resource *result;
int seen_last;
};
static void pick_largest_resource(void *gp, struct device *dev,
struct resource *resource)
{
struct pick_largest_state *state = gp;
struct resource *last;
last = state->last;
/* Be certain to pick the successor to last. */
if (resource == last) {
state->seen_last = 1;
return;
}
if (resource->flags & IORESOURCE_FIXED)
return; /* Skip it. */
if (last && ((last->align < resource->align) ||
((last->align == resource->align) &&
(last->size < resource->size)) ||
((last->align == resource->align) &&
(last->size == resource->size) && (!state->seen_last)))) {
return;
}
if (!state->result ||
(state->result->align < resource->align) ||
((state->result->align == resource->align) &&
(state->result->size < resource->size))) {
state->result_dev = dev;
state->result = resource;
}
}
const struct device *largest_resource(struct bus *bus,
struct resource **result_res,
unsigned long type_mask,
unsigned long type)
{
struct pick_largest_state state;
state.last = *result_res;
state.result_dev = NULL;
state.result = NULL;
state.seen_last = 0;
search_bus_resources(bus, type_mask, type, pick_largest_resource,
&state);
*result_res = state.result;
return state.result_dev;
}