sram-alloc.c

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/*
 * SRAM allocator for Blackfin on-chip memory
 *
 * Copyright 2004-2009 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h>
#include <linux/fcntl.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
#include <linux/rtc.h>
#include <linux/slab.h>
#include <asm/blackfin.h>
#include <asm/mem_map.h>
#include "blackfin_sram.h"

/* the data structure for L1 scratchpad and DATA SRAM */
struct sram_piece {
    void *paddr;
    int size;
    pid_t pid;
    struct sram_piece *next;
};

static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1sram_lock);
static DEFINE_PER_CPU(struct sram_piece, free_l1_ssram_head);
static DEFINE_PER_CPU(struct sram_piece, used_l1_ssram_head);

#if L1_DATA_A_LENGTH != 0
static DEFINE_PER_CPU(struct sram_piece, free_l1_data_A_sram_head);
static DEFINE_PER_CPU(struct sram_piece, used_l1_data_A_sram_head);
#endif

#if L1_DATA_B_LENGTH != 0
static DEFINE_PER_CPU(struct sram_piece, free_l1_data_B_sram_head);
static DEFINE_PER_CPU(struct sram_piece, used_l1_data_B_sram_head);
#endif

#if L1_DATA_A_LENGTH || L1_DATA_B_LENGTH
static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1_data_sram_lock);
#endif

#if L1_CODE_LENGTH != 0
static DEFINE_PER_CPU_SHARED_ALIGNED(spinlock_t, l1_inst_sram_lock);
static DEFINE_PER_CPU(struct sram_piece, free_l1_inst_sram_head);
static DEFINE_PER_CPU(struct sram_piece, used_l1_inst_sram_head);
#endif

#if L2_LENGTH != 0
static spinlock_t l2_sram_lock ____cacheline_aligned_in_smp;
static struct sram_piece free_l2_sram_head, used_l2_sram_head;
#endif

static struct kmem_cache *sram_piece_cache;

/* L1 Scratchpad SRAM initialization function */
static void __init l1sram_init(void)
{
    unsigned int cpu;
    unsigned long reserve;

#ifdef CONFIG_SMP
    reserve = 0;
#else
    reserve = sizeof(struct l1_scratch_task_info);
#endif

    for (cpu = 0; cpu < num_possible_cpus(); ++cpu) {
        per_cpu(free_l1_ssram_head, cpu).next =
            kmem_cache_alloc(sram_piece_cache, GFP_KERNEL);
        if (!per_cpu(free_l1_ssram_head, cpu).next) {
            printk(KERN_INFO "Fail to initialize Scratchpad data SRAM.\n");
            return;
        }

        per_cpu(free_l1_ssram_head, cpu).next->paddr = (void *)get_l1_scratch_start_cpu(cpu) + reserve;
        per_cpu(free_l1_ssram_head, cpu).next->size = L1_SCRATCH_LENGTH - reserve;
        per_cpu(free_l1_ssram_head, cpu).next->pid = 0;
        per_cpu(free_l1_ssram_head, cpu).next->next = NULL;

        per_cpu(used_l1_ssram_head, cpu).next = NULL;

        /* mutex initialize */
        spin_lock_init(&per_cpu(l1sram_lock, cpu));
        printk(KERN_INFO "Blackfin Scratchpad data SRAM: %d KB\n",
            L1_SCRATCH_LENGTH >> 10);
    }
}

static void __init l1_data_sram_init(void)
{
#if L1_DATA_A_LENGTH != 0 || L1_DATA_B_LENGTH != 0
    unsigned int cpu;
#endif
#if L1_DATA_A_LENGTH != 0
    for (cpu = 0; cpu < num_possible_cpus(); ++cpu) {
        per_cpu(free_l1_data_A_sram_head, cpu).next =
            kmem_cache_alloc(sram_piece_cache, GFP_KERNEL);
        if (!per_cpu(free_l1_data_A_sram_head, cpu).next) {
            printk(KERN_INFO "Fail to initialize L1 Data A SRAM.\n");
            return;
        }

        per_cpu(free_l1_data_A_sram_head, cpu).next->paddr =
            (void *)get_l1_data_a_start_cpu(cpu) + (_ebss_l1 - _sdata_l1);
        per_cpu(free_l1_data_A_sram_head, cpu).next->size =
            L1_DATA_A_LENGTH - (_ebss_l1 - _sdata_l1);
        per_cpu(free_l1_data_A_sram_head, cpu).next->pid = 0;
        per_cpu(free_l1_data_A_sram_head, cpu).next->next = NULL;

        per_cpu(used_l1_data_A_sram_head, cpu).next = NULL;

        printk(KERN_INFO "Blackfin L1 Data A SRAM: %d KB (%d KB free)\n",
            L1_DATA_A_LENGTH >> 10,
            per_cpu(free_l1_data_A_sram_head, cpu).next->size >> 10);
    }
#endif
#if L1_DATA_B_LENGTH != 0
    for (cpu = 0; cpu < num_possible_cpus(); ++cpu) {
        per_cpu(free_l1_data_B_sram_head, cpu).next =
            kmem_cache_alloc(sram_piece_cache, GFP_KERNEL);
        if (!per_cpu(free_l1_data_B_sram_head, cpu).next) {
            printk(KERN_INFO "Fail to initialize L1 Data B SRAM.\n");
            return;
        }

        per_cpu(free_l1_data_B_sram_head, cpu).next->paddr =
            (void *)get_l1_data_b_start_cpu(cpu) + (_ebss_b_l1 - _sdata_b_l1);
        per_cpu(free_l1_data_B_sram_head, cpu).next->size =
            L1_DATA_B_LENGTH - (_ebss_b_l1 - _sdata_b_l1);
        per_cpu(free_l1_data_B_sram_head, cpu).next->pid = 0;
        per_cpu(free_l1_data_B_sram_head, cpu).next->next = NULL;

        per_cpu(used_l1_data_B_sram_head, cpu).next = NULL;

        printk(KERN_INFO "Blackfin L1 Data B SRAM: %d KB (%d KB free)\n",
            L1_DATA_B_LENGTH >> 10,
            per_cpu(free_l1_data_B_sram_head, cpu).next->size >> 10);
        /* mutex initialize */
    }
#endif

#if L1_DATA_A_LENGTH != 0 || L1_DATA_B_LENGTH != 0
    for (cpu = 0; cpu < num_possible_cpus(); ++cpu)
        spin_lock_init(&per_cpu(l1_data_sram_lock, cpu));
#endif
}

static void __init l1_inst_sram_init(void)
{
#if L1_CODE_LENGTH != 0
    unsigned int cpu;
    for (cpu = 0; cpu < num_possible_cpus(); ++cpu) {
        per_cpu(free_l1_inst_sram_head, cpu).next =
            kmem_cache_alloc(sram_piece_cache, GFP_KERNEL);
        if (!per_cpu(free_l1_inst_sram_head, cpu).next) {
            printk(KERN_INFO "Failed to initialize L1 Instruction SRAM\n");
            return;
        }

        per_cpu(free_l1_inst_sram_head, cpu).next->paddr =
            (void *)get_l1_code_start_cpu(cpu) + (_etext_l1 - _stext_l1);
        per_cpu(free_l1_inst_sram_head, cpu).next->size =
            L1_CODE_LENGTH - (_etext_l1 - _stext_l1);
        per_cpu(free_l1_inst_sram_head, cpu).next->pid = 0;
        per_cpu(free_l1_inst_sram_head, cpu).next->next = NULL;

        per_cpu(used_l1_inst_sram_head, cpu).next = NULL;

        printk(KERN_INFO "Blackfin L1 Instruction SRAM: %d KB (%d KB free)\n",
            L1_CODE_LENGTH >> 10,
            per_cpu(free_l1_inst_sram_head, cpu).next->size >> 10);

        /* mutex initialize */
        spin_lock_init(&per_cpu(l1_inst_sram_lock, cpu));
    }
#endif
}

#ifdef __ADSPBF60x__
static irqreturn_t l2_ecc_err(int irq, void *dev_id)
{
    int status;

    printk(KERN_ERR "L2 ecc error happend\n");
    status = bfin_read32(L2CTL0_STAT);
    if (status & 0x1)
        printk(KERN_ERR "Core channel error type:0x%x, addr:0x%x\n",
            bfin_read32(L2CTL0_ET0), bfin_read32(L2CTL0_EADDR0));
    if (status & 0x2)
        printk(KERN_ERR "System channel error type:0x%x, addr:0x%x\n",
            bfin_read32(L2CTL0_ET1), bfin_read32(L2CTL0_EADDR1));

    status = status >> 8;
    if (status)
        printk(KERN_ERR "L2 Bank%d error, addr:0x%x\n",
            status, bfin_read32(L2CTL0_ERRADDR0 + status));

    panic("L2 Ecc error");
    return IRQ_HANDLED;
}
#endif

static void __init l2_sram_init(void)
{
#if L2_LENGTH != 0

#ifdef __ADSPBF60x__
    int ret;

    ret = request_irq(IRQ_L2CTL0_ECC_ERR, l2_ecc_err, 0, "l2-ecc-err",
            NULL);
    if (unlikely(ret < 0)) {
        printk(KERN_INFO "Fail to request l2 ecc error interrupt");
        return;
    }
#endif

    free_l2_sram_head.next =
        kmem_cache_alloc(sram_piece_cache, GFP_KERNEL);
    if (!free_l2_sram_head.next) {
        printk(KERN_INFO "Fail to initialize L2 SRAM.\n");
        return;
    }

    free_l2_sram_head.next->paddr =
        (void *)L2_START + (_ebss_l2 - _stext_l2);
    free_l2_sram_head.next->size =
        L2_LENGTH - (_ebss_l2 - _stext_l2);
    free_l2_sram_head.next->pid = 0;
    free_l2_sram_head.next->next = NULL;

    used_l2_sram_head.next = NULL;

    printk(KERN_INFO "Blackfin L2 SRAM: %d KB (%d KB free)\n",
        L2_LENGTH >> 10,
        free_l2_sram_head.next->size >> 10);

    /* mutex initialize */
    spin_lock_init(&l2_sram_lock);
#endif
}

static int __init bfin_sram_init(void)
{
    sram_piece_cache = kmem_cache_create("sram_piece_cache",
                sizeof(struct sram_piece),
                0, SLAB_PANIC, NULL);

    l1sram_init();
    l1_data_sram_init();
    l1_inst_sram_init();
    l2_sram_init();

    return 0;
}
pure_initcall(bfin_sram_init);

/* SRAM allocate function */
static void *_sram_alloc(size_t size, struct sram_piece *pfree_head,
        struct sram_piece *pused_head)
{
    struct sram_piece *pslot, *plast, *pavail;

    if (size <= 0 || !pfree_head || !pused_head)
        return NULL;

    /* Align the size */
    size = (size + 3) & ~3;

    pslot = pfree_head->next;
    plast = pfree_head;

    /* search an available piece slot */
    while (pslot != NULL && size > pslot->size) {
        plast = pslot;
        pslot = pslot->next;
    }

    if (!pslot)
        return NULL;

    if (pslot->size == size) {
        plast->next = pslot->next;
        pavail = pslot;
    } else {
        /* use atomic so our L1 allocator can be used atomically */
        pavail = kmem_cache_alloc(sram_piece_cache, GFP_ATOMIC);

        if (!pavail)
            return NULL;

        pavail->paddr = pslot->paddr;
        pavail->size = size;
        pslot->paddr += size;
        pslot->size -= size;
    }

    pavail->pid = current->pid;

    pslot = pused_head->next;
    plast = pused_head;

    /* insert new piece into used piece list !!! */
    while (pslot != NULL && pavail->paddr < pslot->paddr) {
        plast = pslot;
        pslot = pslot->next;
    }

    pavail->next = pslot;
    plast->next = pavail;

    return pavail->paddr;
}

/* Allocate the largest available block.  */
static void *_sram_alloc_max(struct sram_piece *pfree_head,
                struct sram_piece *pused_head,
                unsigned long *psize)
{
    struct sram_piece *pslot, *pmax;

    if (!pfree_head || !pused_head)
        return NULL;

    pmax = pslot = pfree_head->next;

    /* search an available piece slot */
    while (pslot != NULL) {
        if (pslot->size > pmax->size)
            pmax = pslot;
        pslot = pslot->next;
    }

    if (!pmax)
        return NULL;

    *psize = pmax->size;

    return _sram_alloc(*psize, pfree_head, pused_head);
}

/* SRAM free function */
static int _sram_free(const void *addr,
            struct sram_piece *pfree_head,
            struct sram_piece *pused_head)
{
    struct sram_piece *pslot, *plast, *pavail;

    if (!pfree_head || !pused_head)
        return -1;

    /* search the relevant memory slot */
    pslot = pused_head->next;
    plast = pused_head;

    /* search an available piece slot */
    while (pslot != NULL && pslot->paddr != addr) {
        plast = pslot;
        pslot = pslot->next;
    }

    if (!pslot)
        return -1;

    plast->next = pslot->next;
    pavail = pslot;
    pavail->pid = 0;

    /* insert free pieces back to the free list */
    pslot = pfree_head->next;
    plast = pfree_head;

    while (pslot != NULL && addr > pslot->paddr) {
        plast = pslot;
        pslot = pslot->next;
    }

    if (plast != pfree_head && plast->paddr + plast->size == pavail->paddr) {
        plast->size += pavail->size;
        kmem_cache_free(sram_piece_cache, pavail);
    } else {
        pavail->next = plast->next;
        plast->next = pavail;
        plast = pavail;
    }

    if (pslot && plast->paddr + plast->size == pslot->paddr) {
        plast->size += pslot->size;
        plast->next = pslot->next;
        kmem_cache_free(sram_piece_cache, pslot);
    }

    return 0;
}

int sram_free(const void *addr)
{

#if L1_CODE_LENGTH != 0
    if (addr >= (void *)get_l1_code_start()
         && addr < (void *)(get_l1_code_start() + L1_CODE_LENGTH))
        return l1_inst_sram_free(addr);
    else
#endif
#if L1_DATA_A_LENGTH != 0
    if (addr >= (void *)get_l1_data_a_start()
         && addr < (void *)(get_l1_data_a_start() + L1_DATA_A_LENGTH))
        return l1_data_A_sram_free(addr);
    else
#endif
#if L1_DATA_B_LENGTH != 0
    if (addr >= (void *)get_l1_data_b_start()
         && addr < (void *)(get_l1_data_b_start() + L1_DATA_B_LENGTH))
        return l1_data_B_sram_free(addr);
    else
#endif
#if L2_LENGTH != 0
    if (addr >= (void *)L2_START
         && addr < (void *)(L2_START + L2_LENGTH))
        return l2_sram_free(addr);
    else
#endif
        return -1;
}
EXPORT_SYMBOL(sram_free);

void *l1_data_A_sram_alloc(size_t size)
{
#if L1_DATA_A_LENGTH != 0
    unsigned long flags;
    void *addr;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_data_sram_lock, cpu), flags);

    addr = _sram_alloc(size, &per_cpu(free_l1_data_A_sram_head, cpu),
            &per_cpu(used_l1_data_A_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_data_sram_lock, cpu), flags);

    pr_debug("Allocated address in l1_data_A_sram_alloc is 0x%lx+0x%lx\n",
         (long unsigned int)addr, size);

    return addr;
#else
    return NULL;
#endif
}
EXPORT_SYMBOL(l1_data_A_sram_alloc);

int l1_data_A_sram_free(const void *addr)
{
#if L1_DATA_A_LENGTH != 0
    unsigned long flags;
    int ret;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_data_sram_lock, cpu), flags);

    ret = _sram_free(addr, &per_cpu(free_l1_data_A_sram_head, cpu),
            &per_cpu(used_l1_data_A_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_data_sram_lock, cpu), flags);

    return ret;
#else
    return -1;
#endif
}
EXPORT_SYMBOL(l1_data_A_sram_free);

void *l1_data_B_sram_alloc(size_t size)
{
#if L1_DATA_B_LENGTH != 0
    unsigned long flags;
    void *addr;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_data_sram_lock, cpu), flags);

    addr = _sram_alloc(size, &per_cpu(free_l1_data_B_sram_head, cpu),
            &per_cpu(used_l1_data_B_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_data_sram_lock, cpu), flags);

    pr_debug("Allocated address in l1_data_B_sram_alloc is 0x%lx+0x%lx\n",
         (long unsigned int)addr, size);

    return addr;
#else
    return NULL;
#endif
}
EXPORT_SYMBOL(l1_data_B_sram_alloc);

int l1_data_B_sram_free(const void *addr)
{
#if L1_DATA_B_LENGTH != 0
    unsigned long flags;
    int ret;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_data_sram_lock, cpu), flags);

    ret = _sram_free(addr, &per_cpu(free_l1_data_B_sram_head, cpu),
            &per_cpu(used_l1_data_B_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_data_sram_lock, cpu), flags);

    return ret;
#else
    return -1;
#endif
}
EXPORT_SYMBOL(l1_data_B_sram_free);

void *l1_data_sram_alloc(size_t size)
{
    void *addr = l1_data_A_sram_alloc(size);

    if (!addr)
        addr = l1_data_B_sram_alloc(size);

    return addr;
}
EXPORT_SYMBOL(l1_data_sram_alloc);

void *l1_data_sram_zalloc(size_t size)
{
    void *addr = l1_data_sram_alloc(size);

    if (addr)
        memset(addr, 0x00, size);

    return addr;
}
EXPORT_SYMBOL(l1_data_sram_zalloc);

int l1_data_sram_free(const void *addr)
{
    int ret;
    ret = l1_data_A_sram_free(addr);
    if (ret == -1)
        ret = l1_data_B_sram_free(addr);
    return ret;
}
EXPORT_SYMBOL(l1_data_sram_free);

void *l1_inst_sram_alloc(size_t size)
{
#if L1_CODE_LENGTH != 0
    unsigned long flags;
    void *addr;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_inst_sram_lock, cpu), flags);

    addr = _sram_alloc(size, &per_cpu(free_l1_inst_sram_head, cpu),
            &per_cpu(used_l1_inst_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_inst_sram_lock, cpu), flags);

    pr_debug("Allocated address in l1_inst_sram_alloc is 0x%lx+0x%lx\n",
         (long unsigned int)addr, size);

    return addr;
#else
    return NULL;
#endif
}
EXPORT_SYMBOL(l1_inst_sram_alloc);

int l1_inst_sram_free(const void *addr)
{
#if L1_CODE_LENGTH != 0
    unsigned long flags;
    int ret;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1_inst_sram_lock, cpu), flags);

    ret = _sram_free(addr, &per_cpu(free_l1_inst_sram_head, cpu),
            &per_cpu(used_l1_inst_sram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1_inst_sram_lock, cpu), flags);

    return ret;
#else
    return -1;
#endif
}
EXPORT_SYMBOL(l1_inst_sram_free);

/* L1 Scratchpad memory allocate function */
void *l1sram_alloc(size_t size)
{
    unsigned long flags;
    void *addr;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1sram_lock, cpu), flags);

    addr = _sram_alloc(size, &per_cpu(free_l1_ssram_head, cpu),
            &per_cpu(used_l1_ssram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1sram_lock, cpu), flags);

    return addr;
}

/* L1 Scratchpad memory allocate function */
void *l1sram_alloc_max(size_t *psize)
{
    unsigned long flags;
    void *addr;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1sram_lock, cpu), flags);

    addr = _sram_alloc_max(&per_cpu(free_l1_ssram_head, cpu),
            &per_cpu(used_l1_ssram_head, cpu), psize);

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1sram_lock, cpu), flags);

    return addr;
}

/* L1 Scratchpad memory free function */
int l1sram_free(const void *addr)
{
    unsigned long flags;
    int ret;
    unsigned int cpu;

    cpu = smp_processor_id();
    /* add mutex operation */
    spin_lock_irqsave(&per_cpu(l1sram_lock, cpu), flags);

    ret = _sram_free(addr, &per_cpu(free_l1_ssram_head, cpu),
            &per_cpu(used_l1_ssram_head, cpu));

    /* add mutex operation */
    spin_unlock_irqrestore(&per_cpu(l1sram_lock, cpu), flags);

    return ret;
}

void *l2_sram_alloc(size_t size)
{
#if L2_LENGTH != 0
    unsigned long flags;
    void *addr;

    /* add mutex operation */
    spin_lock_irqsave(&l2_sram_lock, flags);

    addr = _sram_alloc(size, &free_l2_sram_head,
            &used_l2_sram_head);

    /* add mutex operation */
    spin_unlock_irqrestore(&l2_sram_lock, flags);

    pr_debug("Allocated address in l2_sram_alloc is 0x%lx+0x%lx\n",
         (long unsigned int)addr, size);

    return addr;
#else
    return NULL;
#endif
}
EXPORT_SYMBOL(l2_sram_alloc);

void *l2_sram_zalloc(size_t size)
{
    void *addr = l2_sram_alloc(size);

    if (addr)
        memset(addr, 0x00, size);

    return addr;
}
EXPORT_SYMBOL(l2_sram_zalloc);

int l2_sram_free(const void *addr)
{
#if L2_LENGTH != 0
    unsigned long flags;
    int ret;

    /* add mutex operation */
    spin_lock_irqsave(&l2_sram_lock, flags);

    ret = _sram_free(addr, &free_l2_sram_head,
            &used_l2_sram_head);

    /* add mutex operation */
    spin_unlock_irqrestore(&l2_sram_lock, flags);

    return ret;
#else
    return -1;
#endif
}
EXPORT_SYMBOL(l2_sram_free);

int sram_free_with_lsl(const void *addr)
{
    struct sram_list_struct *lsl, **tmp;
    struct mm_struct *mm = current->mm;
    int ret = -1;

    for (tmp = &mm->context.sram_list; *tmp; tmp = &(*tmp)->next)
        if ((*tmp)->addr == addr) {
            lsl = *tmp;
            ret = sram_free(addr);
            *tmp = lsl->next;
            kfree(lsl);
            break;
        }

    return ret;
}
EXPORT_SYMBOL(sram_free_with_lsl);

/* Allocate memory and keep in L1 SRAM List (lsl) so that the resources are
 * tracked.  These are designed for userspace so that when a process exits,
 * we can safely reap their resources.
 */
void *sram_alloc_with_lsl(size_t size, unsigned long flags)
{
    void *addr = NULL;
    struct sram_list_struct *lsl = NULL;
    struct mm_struct *mm = current->mm;

    lsl = kzalloc(sizeof(struct sram_list_struct), GFP_KERNEL);
    if (!lsl)
        return NULL;

    if (flags & L1_INST_SRAM)
        addr = l1_inst_sram_alloc(size);

    if (addr == NULL && (flags & L1_DATA_A_SRAM))
        addr = l1_data_A_sram_alloc(size);

    if (addr == NULL && (flags & L1_DATA_B_SRAM))
        addr = l1_data_B_sram_alloc(size);

    if (addr == NULL && (flags & L2_SRAM))
        addr = l2_sram_alloc(size);

    if (addr == NULL) {
        kfree(lsl);
        return NULL;
    }
    lsl->addr = addr;
    lsl->length = size;
    lsl->next = mm->context.sram_list;
    mm->context.sram_list = lsl;
    return addr;
}
EXPORT_SYMBOL(sram_alloc_with_lsl);

#ifdef CONFIG_PROC_FS
/* Once we get a real allocator, we'll throw all of this away.
 * Until then, we need some sort of visibility into the L1 alloc.
 */
/* Need to keep line of output the same.  Currently, that is 44 bytes
 * (including newline).
 */
static int _sram_proc_show(struct seq_file *m, const char *desc,
        struct sram_piece *pfree_head,
        struct sram_piece *pused_head)
{
    struct sram_piece *pslot;

    if (!pfree_head || !pused_head)
        return -1;

    seq_printf(m, "--- SRAM %-14s Size   PID State     \n", desc);

    /* search the relevant memory slot */
    pslot = pused_head->next;

    while (pslot != NULL) {
        seq_printf(m, "%p-%p %10i %5i %-10s\n",
            pslot->paddr, pslot->paddr + pslot->size,
            pslot->size, pslot->pid, "ALLOCATED");

        pslot = pslot->next;
    }

    pslot = pfree_head->next;

    while (pslot != NULL) {
        seq_printf(m, "%p-%p %10i %5i %-10s\n",
            pslot->paddr, pslot->paddr + pslot->size,
            pslot->size, pslot->pid, "FREE");

        pslot = pslot->next;
    }

    return 0;
}
static int sram_proc_show(struct seq_file *m, void *v)
{
    unsigned int cpu;

    for (cpu = 0; cpu < num_possible_cpus(); ++cpu) {
        if (_sram_proc_show(m, "Scratchpad",
            &per_cpu(free_l1_ssram_head, cpu), &per_cpu(used_l1_ssram_head, cpu)))
            goto not_done;
#if L1_DATA_A_LENGTH != 0
        if (_sram_proc_show(m, "L1 Data A",
            &per_cpu(free_l1_data_A_sram_head, cpu),
            &per_cpu(used_l1_data_A_sram_head, cpu)))
            goto not_done;
#endif
#if L1_DATA_B_LENGTH != 0
        if (_sram_proc_show(m, "L1 Data B",
            &per_cpu(free_l1_data_B_sram_head, cpu),
            &per_cpu(used_l1_data_B_sram_head, cpu)))
            goto not_done;
#endif
#if L1_CODE_LENGTH != 0
        if (_sram_proc_show(m, "L1 Instruction",
            &per_cpu(free_l1_inst_sram_head, cpu),
            &per_cpu(used_l1_inst_sram_head, cpu)))
            goto not_done;
#endif
    }
#if L2_LENGTH != 0
    if (_sram_proc_show(m, "L2", &free_l2_sram_head, &used_l2_sram_head))
        goto not_done;
#endif
 not_done:
    return 0;
}

static int sram_proc_open(struct inode *inode, struct file *file)
{
    return single_open(file, sram_proc_show, NULL);
}

static const struct file_operations sram_proc_ops = {
    .open       = sram_proc_open,
    .read       = seq_read,
    .llseek     = seq_lseek,
    .release    = single_release,
};

static int __init sram_proc_init(void)
{
    struct proc_dir_entry *ptr;

    ptr = proc_create("sram", S_IRUGO, NULL, &sram_proc_ops);
    if (!ptr) {
        printk(KERN_WARNING "unable to create /proc/sram\n");
        return -1;
    }
    return 0;
}
late_initcall(sram_proc_init);
#endif