1/*
  2 * Copyright 2009-2010 Freescale Semiconductor, Inc.
  3 *
  4 * Simple memory allocator abstraction for QorIQ (P1/P2) based Cache-SRAM
  5 *
  6 * Author: Vivek Mahajan <vivek.mahajan@freescale.com>
  7 *
  8 * This file is derived from the original work done
  9 * by Sylvain Munaut for the Bestcomm SRAM allocator.
 10 *
 11 * This program is free software; you can redistribute  it and/or modify it
 12 * under  the terms of  the GNU General  Public License as published by the
 13 * Free Software Foundation;  either version 2 of the  License, or (at your
 14 * option) any later version.
 15 *
 16 * This program is distributed in the hope that it will be useful,
 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 19 * GNU General Public License for more details.
 20 *
 21 * You should have received a copy of the GNU General Public License
 22 * along with this program; if not, write to the Free Software
 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 24 */
 25
 26#include <linux/kernel.h>
 27#include <linux/slab.h>
 28#include <linux/err.h>
 29#include <linux/of_platform.h>
 30#include <asm/pgtable.h>
 31#include <asm/fsl_85xx_cache_sram.h>
 32
 33#include "fsl_85xx_cache_ctlr.h"
 34
 35struct mpc85xx_cache_sram *cache_sram;
 36
 37void *mpc85xx_cache_sram_alloc(unsigned int size,
 38				phys_addr_t *phys, unsigned int align)
 39{
 40	unsigned long offset;
 41	unsigned long flags;
 42
 43	if (unlikely(cache_sram == NULL))
 44		return NULL;
 45
 46	if (!size || (size > cache_sram->size) || (align > cache_sram->size)) {
 47		pr_err("%s(): size(=%x) or align(=%x) zero or too big\n",
 48			__func__, size, align);
 49		return NULL;
 50	}
 51
 52	if ((align & (align - 1)) || align <= 1) {
 53		pr_err("%s(): align(=%x) must be power of two and >1\n",
 54			__func__, align);
 55		return NULL;
 56	}
 57
 58	spin_lock_irqsave(&cache_sram->lock, flags);
 59	offset = rh_alloc_align(cache_sram->rh, size, align, NULL);
 60	spin_unlock_irqrestore(&cache_sram->lock, flags);
 61
 62	if (IS_ERR_VALUE(offset))
 63		return NULL;
 64
 65	*phys = cache_sram->base_phys + offset;
 66
 67	return (unsigned char *)cache_sram->base_virt + offset;
 68}
 69EXPORT_SYMBOL(mpc85xx_cache_sram_alloc);
 70
 71void mpc85xx_cache_sram_free(void *ptr)
 72{
 73	unsigned long flags;
 74	BUG_ON(!ptr);
 75
 76	spin_lock_irqsave(&cache_sram->lock, flags);
 77	rh_free(cache_sram->rh, ptr - cache_sram->base_virt);
 78	spin_unlock_irqrestore(&cache_sram->lock, flags);
 79}
 80EXPORT_SYMBOL(mpc85xx_cache_sram_free);
 81
 82int __init instantiate_cache_sram(struct platform_device *dev,
 83		struct sram_parameters sram_params)
 84{
 85	int ret = 0;
 86
 87	if (cache_sram) {
 88		dev_err(&dev->dev, "Already initialized cache-sram\n");
 89		return -EBUSY;
 90	}
 91
 92	cache_sram = kzalloc(sizeof(struct mpc85xx_cache_sram), GFP_KERNEL);
 93	if (!cache_sram) {
 94		dev_err(&dev->dev, "Out of memory for cache_sram structure\n");
 95		return -ENOMEM;
 96	}
 97
 98	cache_sram->base_phys = sram_params.sram_offset;
 99	cache_sram->size = sram_params.sram_size;
100
101	if (!request_mem_region(cache_sram->base_phys, cache_sram->size,
102						"fsl_85xx_cache_sram")) {
103		dev_err(&dev->dev, "%s: request memory failed\n",
104				dev->dev.of_node->full_name);
105		ret = -ENXIO;
106		goto out_free;
107	}
108
109	cache_sram->base_virt = ioremap_prot(cache_sram->base_phys,
110				cache_sram->size, _PAGE_COHERENT | PAGE_KERNEL);
111	if (!cache_sram->base_virt) {
112		dev_err(&dev->dev, "%s: ioremap_prot failed\n",
113				dev->dev.of_node->full_name);
114		ret = -ENOMEM;
115		goto out_release;
116	}
117
118	cache_sram->rh = rh_create(sizeof(unsigned int));
119	if (IS_ERR(cache_sram->rh)) {
120		dev_err(&dev->dev, "%s: Unable to create remote heap\n",
121				dev->dev.of_node->full_name);
122		ret = PTR_ERR(cache_sram->rh);
123		goto out_unmap;
124	}
125
126	rh_attach_region(cache_sram->rh, 0, cache_sram->size);
127	spin_lock_init(&cache_sram->lock);
128
129	dev_info(&dev->dev, "[base:0x%llx, size:0x%x] configured and loaded\n",
130		(unsigned long long)cache_sram->base_phys, cache_sram->size);
131
132	return 0;
133
134out_unmap:
135	iounmap(cache_sram->base_virt);
136
137out_release:
138	release_mem_region(cache_sram->base_phys, cache_sram->size);
139
140out_free:
141	kfree(cache_sram);
142	return ret;
143}
144
145void remove_cache_sram(struct platform_device *dev)
146{
147	BUG_ON(!cache_sram);
148
149	rh_detach_region(cache_sram->rh, 0, cache_sram->size);
150	rh_destroy(cache_sram->rh);
151
152	iounmap(cache_sram->base_virt);
153	release_mem_region(cache_sram->base_phys, cache_sram->size);
154
155	kfree(cache_sram);
156	cache_sram = NULL;
157
158	dev_info(&dev->dev, "MPC85xx Cache-SRAM driver unloaded\n");
159}