1*2874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 220e9969bSDavid Brownell /* 320e9969bSDavid Brownell * mach-davinci/sram.c - DaVinci simple SRAM allocator 420e9969bSDavid Brownell * 520e9969bSDavid Brownell * Copyright (C) 2009 David Brownell 620e9969bSDavid Brownell */ 720e9969bSDavid Brownell #include <linux/module.h> 820e9969bSDavid Brownell #include <linux/init.h> 9626863a3SBen Gardiner #include <linux/io.h> 1020e9969bSDavid Brownell #include <linux/genalloc.h> 1120e9969bSDavid Brownell 1220e9969bSDavid Brownell #include <mach/common.h> 133acf731cSArnd Bergmann #include "sram.h" 1420e9969bSDavid Brownell 1520e9969bSDavid Brownell static struct gen_pool *sram_pool; 1620e9969bSDavid Brownell 17983c42baSMatt Porter struct gen_pool *sram_get_gen_pool(void) 18983c42baSMatt Porter { 19983c42baSMatt Porter return sram_pool; 20983c42baSMatt Porter } 21983c42baSMatt Porter 2220e9969bSDavid Brownell void *sram_alloc(size_t len, dma_addr_t *dma) 2320e9969bSDavid Brownell { 2420e9969bSDavid Brownell dma_addr_t dma_base = davinci_soc_info.sram_dma; 2520e9969bSDavid Brownell 2620e9969bSDavid Brownell if (dma) 2720e9969bSDavid Brownell *dma = 0; 2820e9969bSDavid Brownell if (!sram_pool || (dma && !dma_base)) 2920e9969bSDavid Brownell return NULL; 3020e9969bSDavid Brownell 3166f11969SNicolin Chen return gen_pool_dma_alloc(sram_pool, len, dma); 3220e9969bSDavid Brownell 3320e9969bSDavid Brownell } 3420e9969bSDavid Brownell EXPORT_SYMBOL(sram_alloc); 3520e9969bSDavid Brownell 3620e9969bSDavid Brownell void sram_free(void *addr, size_t len) 3720e9969bSDavid Brownell { 3820e9969bSDavid Brownell gen_pool_free(sram_pool, (unsigned long) addr, len); 3920e9969bSDavid Brownell } 4020e9969bSDavid Brownell EXPORT_SYMBOL(sram_free); 4120e9969bSDavid Brownell 4220e9969bSDavid Brownell 4320e9969bSDavid Brownell /* 4420e9969bSDavid Brownell * REVISIT This supports CPU and DMA access to/from SRAM, but it 4520e9969bSDavid Brownell * doesn't (yet?) support some other notable uses of SRAM: as TCM 4620e9969bSDavid Brownell * for data and/or instructions; and holding code needed to enter 4720e9969bSDavid Brownell * and exit suspend states (while DRAM can't be used). 4820e9969bSDavid Brownell */ 4920e9969bSDavid Brownell static int __init sram_init(void) 5020e9969bSDavid Brownell { 51626863a3SBen Gardiner phys_addr_t phys = davinci_soc_info.sram_dma; 5220e9969bSDavid Brownell unsigned len = davinci_soc_info.sram_len; 5320e9969bSDavid Brownell int status = 0; 54182e7961SSekhar Nori void __iomem *addr; 5520e9969bSDavid Brownell 5620e9969bSDavid Brownell if (len) { 571d3bba61SDavid Brownell len = min_t(unsigned, len, SRAM_SIZE); 5820e9969bSDavid Brownell sram_pool = gen_pool_create(ilog2(SRAM_GRANULARITY), -1); 5920e9969bSDavid Brownell if (!sram_pool) 6020e9969bSDavid Brownell status = -ENOMEM; 6120e9969bSDavid Brownell } 62626863a3SBen Gardiner 63626863a3SBen Gardiner if (sram_pool) { 64626863a3SBen Gardiner addr = ioremap(phys, len); 65626863a3SBen Gardiner if (!addr) 66626863a3SBen Gardiner return -ENOMEM; 67182e7961SSekhar Nori status = gen_pool_add_virt(sram_pool, (unsigned long) addr, 68626863a3SBen Gardiner phys, len, -1); 69626863a3SBen Gardiner if (status < 0) 70626863a3SBen Gardiner iounmap(addr); 71626863a3SBen Gardiner } 72626863a3SBen Gardiner 7320e9969bSDavid Brownell WARN_ON(status < 0); 7420e9969bSDavid Brownell return status; 7520e9969bSDavid Brownell } 7620e9969bSDavid Brownell core_initcall(sram_init); 7720e9969bSDavid Brownell 78