mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
8bb0daffb0
Now that the omapdss interface has been reworked so that omapdrm can use dispc directly, we have been able to fix the remaining functional kms issues with omapdrm. And in the mean time the PM sequencing and many other of that open issues have been solved. So I think it makes sense to finally move omapdrm out of staging. Signed-off-by: Rob Clark <robdclark@gmail.com>
704 lines
18 KiB
C
704 lines
18 KiB
C
/*
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* tcm-sita.c
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*
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* SImple Tiler Allocator (SiTA): 2D and 1D allocation(reservation) algorithm
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*
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* Authors: Ravi Ramachandra <r.ramachandra@ti.com>,
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* Lajos Molnar <molnar@ti.com>
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*
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* Copyright (C) 2009-2010 Texas Instruments, Inc.
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*
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* This package is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*
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*/
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include "tcm-sita.h"
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#define ALIGN_DOWN(value, align) ((value) & ~((align) - 1))
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/* Individual selection criteria for different scan areas */
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static s32 CR_L2R_T2B = CR_BIAS_HORIZONTAL;
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static s32 CR_R2L_T2B = CR_DIAGONAL_BALANCE;
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/*********************************************
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* TCM API - Sita Implementation
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*********************************************/
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static s32 sita_reserve_2d(struct tcm *tcm, u16 h, u16 w, u8 align,
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struct tcm_area *area);
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static s32 sita_reserve_1d(struct tcm *tcm, u32 slots, struct tcm_area *area);
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static s32 sita_free(struct tcm *tcm, struct tcm_area *area);
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static void sita_deinit(struct tcm *tcm);
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/*********************************************
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* Main Scanner functions
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*********************************************/
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static s32 scan_areas_and_find_fit(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *area);
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static s32 scan_l2r_t2b(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *field, struct tcm_area *area);
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static s32 scan_r2l_t2b(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *field, struct tcm_area *area);
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static s32 scan_r2l_b2t_one_dim(struct tcm *tcm, u32 num_slots,
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struct tcm_area *field, struct tcm_area *area);
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/*********************************************
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* Support Infrastructure Methods
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*********************************************/
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static s32 is_area_free(struct tcm_area ***map, u16 x0, u16 y0, u16 w, u16 h);
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static s32 update_candidate(struct tcm *tcm, u16 x0, u16 y0, u16 w, u16 h,
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struct tcm_area *field, s32 criteria,
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struct score *best);
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static void get_nearness_factor(struct tcm_area *field,
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struct tcm_area *candidate,
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struct nearness_factor *nf);
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static void get_neighbor_stats(struct tcm *tcm, struct tcm_area *area,
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struct neighbor_stats *stat);
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static void fill_area(struct tcm *tcm,
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struct tcm_area *area, struct tcm_area *parent);
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/*********************************************/
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/*********************************************
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* Utility Methods
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*********************************************/
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struct tcm *sita_init(u16 width, u16 height, struct tcm_pt *attr)
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{
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struct tcm *tcm;
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struct sita_pvt *pvt;
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struct tcm_area area = {0};
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s32 i;
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if (width == 0 || height == 0)
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return NULL;
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tcm = kmalloc(sizeof(*tcm), GFP_KERNEL);
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pvt = kmalloc(sizeof(*pvt), GFP_KERNEL);
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if (!tcm || !pvt)
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goto error;
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memset(tcm, 0, sizeof(*tcm));
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memset(pvt, 0, sizeof(*pvt));
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/* Updating the pointers to SiTA implementation APIs */
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tcm->height = height;
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tcm->width = width;
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tcm->reserve_2d = sita_reserve_2d;
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tcm->reserve_1d = sita_reserve_1d;
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tcm->free = sita_free;
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tcm->deinit = sita_deinit;
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tcm->pvt = (void *)pvt;
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spin_lock_init(&(pvt->lock));
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/* Creating tam map */
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pvt->map = kmalloc(sizeof(*pvt->map) * tcm->width, GFP_KERNEL);
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if (!pvt->map)
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goto error;
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for (i = 0; i < tcm->width; i++) {
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pvt->map[i] =
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kmalloc(sizeof(**pvt->map) * tcm->height,
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GFP_KERNEL);
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if (pvt->map[i] == NULL) {
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while (i--)
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kfree(pvt->map[i]);
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kfree(pvt->map);
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goto error;
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}
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}
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if (attr && attr->x <= tcm->width && attr->y <= tcm->height) {
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pvt->div_pt.x = attr->x;
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pvt->div_pt.y = attr->y;
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} else {
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/* Defaulting to 3:1 ratio on width for 2D area split */
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/* Defaulting to 3:1 ratio on height for 2D and 1D split */
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pvt->div_pt.x = (tcm->width * 3) / 4;
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pvt->div_pt.y = (tcm->height * 3) / 4;
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}
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spin_lock(&(pvt->lock));
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assign(&area, 0, 0, width - 1, height - 1);
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fill_area(tcm, &area, NULL);
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spin_unlock(&(pvt->lock));
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return tcm;
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error:
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kfree(tcm);
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kfree(pvt);
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return NULL;
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}
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static void sita_deinit(struct tcm *tcm)
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{
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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struct tcm_area area = {0};
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s32 i;
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area.p1.x = tcm->width - 1;
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area.p1.y = tcm->height - 1;
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spin_lock(&(pvt->lock));
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fill_area(tcm, &area, NULL);
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spin_unlock(&(pvt->lock));
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for (i = 0; i < tcm->height; i++)
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kfree(pvt->map[i]);
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kfree(pvt->map);
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kfree(pvt);
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}
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/**
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* Reserve a 1D area in the container
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*
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* @param num_slots size of 1D area
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* @param area pointer to the area that will be populated with the
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* reserved area
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 sita_reserve_1d(struct tcm *tcm, u32 num_slots,
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struct tcm_area *area)
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{
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s32 ret;
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struct tcm_area field = {0};
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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spin_lock(&(pvt->lock));
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/* Scanning entire container */
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assign(&field, tcm->width - 1, tcm->height - 1, 0, 0);
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ret = scan_r2l_b2t_one_dim(tcm, num_slots, &field, area);
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if (!ret)
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/* update map */
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fill_area(tcm, area, area);
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spin_unlock(&(pvt->lock));
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return ret;
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}
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/**
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* Reserve a 2D area in the container
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*
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* @param w width
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* @param h height
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* @param area pointer to the area that will be populated with the reserved
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* area
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 sita_reserve_2d(struct tcm *tcm, u16 h, u16 w, u8 align,
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struct tcm_area *area)
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{
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s32 ret;
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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/* not supporting more than 64 as alignment */
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if (align > 64)
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return -EINVAL;
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/* we prefer 1, 32 and 64 as alignment */
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align = align <= 1 ? 1 : align <= 32 ? 32 : 64;
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spin_lock(&(pvt->lock));
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ret = scan_areas_and_find_fit(tcm, w, h, align, area);
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if (!ret)
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/* update map */
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fill_area(tcm, area, area);
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spin_unlock(&(pvt->lock));
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return ret;
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}
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/**
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* Unreserve a previously allocated 2D or 1D area
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* @param area area to be freed
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* @return 0 - success
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*/
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static s32 sita_free(struct tcm *tcm, struct tcm_area *area)
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{
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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spin_lock(&(pvt->lock));
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/* check that this is in fact an existing area */
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WARN_ON(pvt->map[area->p0.x][area->p0.y] != area ||
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pvt->map[area->p1.x][area->p1.y] != area);
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/* Clear the contents of the associated tiles in the map */
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fill_area(tcm, area, NULL);
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spin_unlock(&(pvt->lock));
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return 0;
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}
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/**
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* Note: In general the cordinates in the scan field area relevant to the can
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* sweep directions. The scan origin (e.g. top-left corner) will always be
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* the p0 member of the field. Therfore, for a scan from top-left p0.x <= p1.x
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* and p0.y <= p1.y; whereas, for a scan from bottom-right p1.x <= p0.x and p1.y
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* <= p0.y
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*/
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/**
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* Raster scan horizontally right to left from top to bottom to find a place for
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* a 2D area of given size inside a scan field.
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*
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* @param w width of desired area
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* @param h height of desired area
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* @param align desired area alignment
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* @param area pointer to the area that will be set to the best position
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* @param field area to scan (inclusive)
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 scan_r2l_t2b(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *field, struct tcm_area *area)
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{
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s32 x, y;
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s16 start_x, end_x, start_y, end_y, found_x = -1;
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struct tcm_area ***map = ((struct sita_pvt *)tcm->pvt)->map;
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struct score best = {{0}, {0}, {0}, 0};
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start_x = field->p0.x;
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end_x = field->p1.x;
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start_y = field->p0.y;
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end_y = field->p1.y;
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/* check scan area co-ordinates */
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if (field->p0.x < field->p1.x ||
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field->p1.y < field->p0.y)
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return -EINVAL;
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/* check if allocation would fit in scan area */
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if (w > LEN(start_x, end_x) || h > LEN(end_y, start_y))
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return -ENOSPC;
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/* adjust start_x and end_y, as allocation would not fit beyond */
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start_x = ALIGN_DOWN(start_x - w + 1, align); /* - 1 to be inclusive */
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end_y = end_y - h + 1;
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/* check if allocation would still fit in scan area */
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if (start_x < end_x)
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return -ENOSPC;
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/* scan field top-to-bottom, right-to-left */
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for (y = start_y; y <= end_y; y++) {
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for (x = start_x; x >= end_x; x -= align) {
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if (is_area_free(map, x, y, w, h)) {
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found_x = x;
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/* update best candidate */
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if (update_candidate(tcm, x, y, w, h, field,
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CR_R2L_T2B, &best))
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goto done;
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/* change upper x bound */
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end_x = x + 1;
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break;
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} else if (map[x][y] && map[x][y]->is2d) {
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/* step over 2D areas */
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x = ALIGN(map[x][y]->p0.x - w + 1, align);
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}
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}
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/* break if you find a free area shouldering the scan field */
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if (found_x == start_x)
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break;
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}
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if (!best.a.tcm)
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return -ENOSPC;
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done:
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assign(area, best.a.p0.x, best.a.p0.y, best.a.p1.x, best.a.p1.y);
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return 0;
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}
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/**
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* Raster scan horizontally left to right from top to bottom to find a place for
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* a 2D area of given size inside a scan field.
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*
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* @param w width of desired area
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* @param h height of desired area
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* @param align desired area alignment
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* @param area pointer to the area that will be set to the best position
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* @param field area to scan (inclusive)
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 scan_l2r_t2b(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *field, struct tcm_area *area)
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{
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s32 x, y;
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s16 start_x, end_x, start_y, end_y, found_x = -1;
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struct tcm_area ***map = ((struct sita_pvt *)tcm->pvt)->map;
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struct score best = {{0}, {0}, {0}, 0};
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start_x = field->p0.x;
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end_x = field->p1.x;
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start_y = field->p0.y;
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end_y = field->p1.y;
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/* check scan area co-ordinates */
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if (field->p1.x < field->p0.x ||
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field->p1.y < field->p0.y)
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return -EINVAL;
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/* check if allocation would fit in scan area */
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if (w > LEN(end_x, start_x) || h > LEN(end_y, start_y))
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return -ENOSPC;
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start_x = ALIGN(start_x, align);
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/* check if allocation would still fit in scan area */
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if (w > LEN(end_x, start_x))
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return -ENOSPC;
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/* adjust end_x and end_y, as allocation would not fit beyond */
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end_x = end_x - w + 1; /* + 1 to be inclusive */
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end_y = end_y - h + 1;
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/* scan field top-to-bottom, left-to-right */
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for (y = start_y; y <= end_y; y++) {
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for (x = start_x; x <= end_x; x += align) {
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if (is_area_free(map, x, y, w, h)) {
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found_x = x;
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/* update best candidate */
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if (update_candidate(tcm, x, y, w, h, field,
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CR_L2R_T2B, &best))
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goto done;
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/* change upper x bound */
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end_x = x - 1;
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break;
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} else if (map[x][y] && map[x][y]->is2d) {
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/* step over 2D areas */
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x = ALIGN_DOWN(map[x][y]->p1.x, align);
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}
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}
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/* break if you find a free area shouldering the scan field */
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if (found_x == start_x)
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break;
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}
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if (!best.a.tcm)
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return -ENOSPC;
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done:
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assign(area, best.a.p0.x, best.a.p0.y, best.a.p1.x, best.a.p1.y);
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return 0;
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}
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/**
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* Raster scan horizontally right to left from bottom to top to find a place
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* for a 1D area of given size inside a scan field.
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*
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* @param num_slots size of desired area
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* @param align desired area alignment
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* @param area pointer to the area that will be set to the best
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* position
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* @param field area to scan (inclusive)
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 scan_r2l_b2t_one_dim(struct tcm *tcm, u32 num_slots,
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struct tcm_area *field, struct tcm_area *area)
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{
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s32 found = 0;
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s16 x, y;
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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struct tcm_area *p;
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/* check scan area co-ordinates */
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if (field->p0.y < field->p1.y)
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return -EINVAL;
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/**
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* Currently we only support full width 1D scan field, which makes sense
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* since 1D slot-ordering spans the full container width.
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*/
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if (tcm->width != field->p0.x - field->p1.x + 1)
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return -EINVAL;
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/* check if allocation would fit in scan area */
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if (num_slots > tcm->width * LEN(field->p0.y, field->p1.y))
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return -ENOSPC;
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x = field->p0.x;
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y = field->p0.y;
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/* find num_slots consecutive free slots to the left */
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while (found < num_slots) {
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if (y < 0)
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return -ENOSPC;
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/* remember bottom-right corner */
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if (found == 0) {
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area->p1.x = x;
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area->p1.y = y;
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}
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/* skip busy regions */
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p = pvt->map[x][y];
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if (p) {
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/* move to left of 2D areas, top left of 1D */
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x = p->p0.x;
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if (!p->is2d)
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y = p->p0.y;
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/* start over */
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found = 0;
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} else {
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/* count consecutive free slots */
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found++;
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if (found == num_slots)
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break;
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}
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/* move to the left */
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if (x == 0)
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y--;
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x = (x ? : tcm->width) - 1;
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}
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/* set top-left corner */
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area->p0.x = x;
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area->p0.y = y;
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return 0;
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}
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/**
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* Find a place for a 2D area of given size inside a scan field based on its
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* alignment needs.
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*
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* @param w width of desired area
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* @param h height of desired area
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* @param align desired area alignment
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* @param area pointer to the area that will be set to the best position
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*
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* @return 0 on success, non-0 error value on failure.
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*/
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static s32 scan_areas_and_find_fit(struct tcm *tcm, u16 w, u16 h, u16 align,
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struct tcm_area *area)
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{
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s32 ret = 0;
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struct tcm_area field = {0};
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u16 boundary_x, boundary_y;
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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if (align > 1) {
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/* prefer top-left corner */
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boundary_x = pvt->div_pt.x - 1;
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boundary_y = pvt->div_pt.y - 1;
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/* expand width and height if needed */
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if (w > pvt->div_pt.x)
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boundary_x = tcm->width - 1;
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if (h > pvt->div_pt.y)
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boundary_y = tcm->height - 1;
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assign(&field, 0, 0, boundary_x, boundary_y);
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ret = scan_l2r_t2b(tcm, w, h, align, &field, area);
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/* scan whole container if failed, but do not scan 2x */
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if (ret != 0 && (boundary_x != tcm->width - 1 ||
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boundary_y != tcm->height - 1)) {
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/* scan the entire container if nothing found */
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assign(&field, 0, 0, tcm->width - 1, tcm->height - 1);
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ret = scan_l2r_t2b(tcm, w, h, align, &field, area);
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}
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} else if (align == 1) {
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/* prefer top-right corner */
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boundary_x = pvt->div_pt.x;
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boundary_y = pvt->div_pt.y - 1;
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/* expand width and height if needed */
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if (w > (tcm->width - pvt->div_pt.x))
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boundary_x = 0;
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if (h > pvt->div_pt.y)
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boundary_y = tcm->height - 1;
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assign(&field, tcm->width - 1, 0, boundary_x, boundary_y);
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ret = scan_r2l_t2b(tcm, w, h, align, &field, area);
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/* scan whole container if failed, but do not scan 2x */
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if (ret != 0 && (boundary_x != 0 ||
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boundary_y != tcm->height - 1)) {
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/* scan the entire container if nothing found */
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assign(&field, tcm->width - 1, 0, 0, tcm->height - 1);
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ret = scan_r2l_t2b(tcm, w, h, align, &field,
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area);
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}
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}
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return ret;
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}
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/* check if an entire area is free */
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static s32 is_area_free(struct tcm_area ***map, u16 x0, u16 y0, u16 w, u16 h)
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{
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u16 x = 0, y = 0;
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for (y = y0; y < y0 + h; y++) {
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for (x = x0; x < x0 + w; x++) {
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if (map[x][y])
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return false;
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}
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}
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return true;
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}
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/* fills an area with a parent tcm_area */
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static void fill_area(struct tcm *tcm, struct tcm_area *area,
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struct tcm_area *parent)
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{
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s32 x, y;
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struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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struct tcm_area a, a_;
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/* set area's tcm; otherwise, enumerator considers it invalid */
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area->tcm = tcm;
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tcm_for_each_slice(a, *area, a_) {
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for (x = a.p0.x; x <= a.p1.x; ++x)
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for (y = a.p0.y; y <= a.p1.y; ++y)
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pvt->map[x][y] = parent;
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}
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}
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/**
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* Compares a candidate area to the current best area, and if it is a better
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* fit, it updates the best to this one.
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*
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* @param x0, y0, w, h top, left, width, height of candidate area
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* @param field scan field
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* @param criteria scan criteria
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* @param best best candidate and its scores
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*
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* @return 1 (true) if the candidate area is known to be the final best, so no
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* more searching should be performed
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*/
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static s32 update_candidate(struct tcm *tcm, u16 x0, u16 y0, u16 w, u16 h,
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struct tcm_area *field, s32 criteria,
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struct score *best)
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{
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struct score me; /* score for area */
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/*
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* NOTE: For horizontal bias we always give the first found, because our
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* scan is horizontal-raster-based and the first candidate will always
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* have the horizontal bias.
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*/
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bool first = criteria & CR_BIAS_HORIZONTAL;
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assign(&me.a, x0, y0, x0 + w - 1, y0 + h - 1);
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/* calculate score for current candidate */
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if (!first) {
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get_neighbor_stats(tcm, &me.a, &me.n);
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me.neighs = me.n.edge + me.n.busy;
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get_nearness_factor(field, &me.a, &me.f);
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}
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/* the 1st candidate is always the best */
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if (!best->a.tcm)
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goto better;
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BUG_ON(first);
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/* diagonal balance check */
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if ((criteria & CR_DIAGONAL_BALANCE) &&
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best->neighs <= me.neighs &&
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(best->neighs < me.neighs ||
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/* this implies that neighs and occupied match */
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best->n.busy < me.n.busy ||
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(best->n.busy == me.n.busy &&
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/* check the nearness factor */
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best->f.x + best->f.y > me.f.x + me.f.y)))
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goto better;
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/* not better, keep going */
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return 0;
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better:
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|
/* save current area as best */
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memcpy(best, &me, sizeof(me));
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best->a.tcm = tcm;
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return first;
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}
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/**
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* Calculate the nearness factor of an area in a search field. The nearness
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* factor is smaller if the area is closer to the search origin.
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|
*/
|
|
static void get_nearness_factor(struct tcm_area *field, struct tcm_area *area,
|
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struct nearness_factor *nf)
|
|
{
|
|
/**
|
|
* Using signed math as field coordinates may be reversed if
|
|
* search direction is right-to-left or bottom-to-top.
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|
*/
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|
nf->x = (s32)(area->p0.x - field->p0.x) * 1000 /
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(field->p1.x - field->p0.x);
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nf->y = (s32)(area->p0.y - field->p0.y) * 1000 /
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(field->p1.y - field->p0.y);
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}
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|
|
|
/* get neighbor statistics */
|
|
static void get_neighbor_stats(struct tcm *tcm, struct tcm_area *area,
|
|
struct neighbor_stats *stat)
|
|
{
|
|
s16 x = 0, y = 0;
|
|
struct sita_pvt *pvt = (struct sita_pvt *)tcm->pvt;
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|
|
|
/* Clearing any exisiting values */
|
|
memset(stat, 0, sizeof(*stat));
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|
|
|
/* process top & bottom edges */
|
|
for (x = area->p0.x; x <= area->p1.x; x++) {
|
|
if (area->p0.y == 0)
|
|
stat->edge++;
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|
else if (pvt->map[x][area->p0.y - 1])
|
|
stat->busy++;
|
|
|
|
if (area->p1.y == tcm->height - 1)
|
|
stat->edge++;
|
|
else if (pvt->map[x][area->p1.y + 1])
|
|
stat->busy++;
|
|
}
|
|
|
|
/* process left & right edges */
|
|
for (y = area->p0.y; y <= area->p1.y; ++y) {
|
|
if (area->p0.x == 0)
|
|
stat->edge++;
|
|
else if (pvt->map[area->p0.x - 1][y])
|
|
stat->busy++;
|
|
|
|
if (area->p1.x == tcm->width - 1)
|
|
stat->edge++;
|
|
else if (pvt->map[area->p1.x + 1][y])
|
|
stat->busy++;
|
|
}
|
|
}
|