drivers/staging/octeon/ethernet-mem.c

   1 /**********************************************************************
   2  * Author: Cavium Networks
   3  *
   4  * Contact: support@caviumnetworks.com
   5  * This file is part of the OCTEON SDK
   6  *
   7  * Copyright (c) 2003-2010 Cavium Networks
   8  *
   9  * This file is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License, Version 2, as
  11  * published by the Free Software Foundation.
  12  *
  13  * This file is distributed in the hope that it will be useful, but
  14  * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
  15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
  16  * NONINFRINGEMENT.  See the GNU General Public License for more
  17  * details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this file; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  22  * or visit http://www.gnu.org/licenses/.
  23  *
  24  * This file may also be available under a different license from Cavium.
  25  * Contact Cavium Networks for more information
  26 **********************************************************************/
  27 #include <linux/kernel.h>
  28 #include <linux/netdevice.h>
  29 #include <linux/slab.h>
  30
  31 #include <asm/octeon/octeon.h>
  32
  33 #include "ethernet-mem.h"
  34 #include "ethernet-defines.h"
  35
  36 #include <asm/octeon/cvmx-fpa.h>
  37
  38 /**
  39  * cvm_oct_fill_hw_skbuff - fill the supplied hardware pool with skbuffs
  40  * @pool:     Pool to allocate an skbuff for
  41  * @size:     Size of the buffer needed for the pool
  42  * @elements: Number of buffers to allocate
  43  *
  44  * Returns the actual number of buffers allocated.
  45  */
  46 static int cvm_oct_fill_hw_skbuff(int pool, int size, int elements)
  47 {
  48         int freed = elements;
  49
  50         while (freed) {
  51                 struct sk_buff *skb = dev_alloc_skb(size + 256);
  52
  53                 if (unlikely(skb == NULL))
  54                         break;
  55                 skb_reserve(skb, 256 - (((unsigned long)skb->data) & 0x7f));
  56                 *(struct sk_buff **)(skb->data - sizeof(void *)) = skb;
  57                 cvmx_fpa_free(skb->data, pool, size / 128);
  58                 freed--;
  59         }
  60         return elements - freed;
  61 }
  62
  63 /**
  64  * cvm_oct_free_hw_skbuff- free hardware pool skbuffs
  65  * @pool:     Pool to allocate an skbuff for
  66  * @size:     Size of the buffer needed for the pool
  67  * @elements: Number of buffers to allocate
  68  */
  69 static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
  70 {
  71         char *memory;
  72
  73         do {
  74                 memory = cvmx_fpa_alloc(pool);
  75                 if (memory) {
  76                         struct sk_buff *skb =
  77                             *(struct sk_buff **)(memory - sizeof(void *));
  78                         elements--;
  79                         dev_kfree_skb(skb);
  80                 }
  81         } while (memory);
  82
  83         if (elements < 0)
  84                 pr_warn("Freeing of pool %u had too many skbuffs (%d)\n",
  85                         pool, elements);
  86         else if (elements > 0)
  87                 pr_warn("Freeing of pool %u is missing %d skbuffs\n",
  88                         pool, elements);
  89 }
  90
  91 /**
  92  * cvm_oct_fill_hw_memory - fill a hardware pool with memory.
  93  * @pool:     Pool to populate
  94  * @size:     Size of each buffer in the pool
  95  * @elements: Number of buffers to allocate
  96  *
  97  * Returns the actual number of buffers allocated.
  98  */
  99 static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
 100 {
 101         char *memory;
 102         char *fpa;
 103         int freed = elements;
 104
 105         while (freed) {
 106                 /*
 107                  * FPA memory must be 128 byte aligned.  Since we are
 108                  * aligning we need to save the original pointer so we
 109                  * can feed it to kfree when the memory is returned to
 110                  * the kernel.
 111                  *
 112                  * We allocate an extra 256 bytes to allow for
 113                  * alignment and space for the original pointer saved
 114                  * just before the block.
 115                  */
 116                 memory = kmalloc(size + 256, GFP_ATOMIC);
 117                 if (unlikely(memory == NULL)) {
 118                         pr_warn("Unable to allocate %u bytes for FPA pool %d\n",
 119                                 elements * size, pool);
 120                         break;
 121                 }
 122                 fpa = (char *)(((unsigned long)memory + 256) & ~0x7fUL);
 123                 *((char **)fpa - 1) = memory;
 124                 cvmx_fpa_free(fpa, pool, 0);
 125                 freed--;
 126         }
 127         return elements - freed;
 128 }
 129
 130 /**
 131  * cvm_oct_free_hw_memory - Free memory allocated by cvm_oct_fill_hw_memory
 132  * @pool:     FPA pool to free
 133  * @size:     Size of each buffer in the pool
 134  * @elements: Number of buffers that should be in the pool
 135  */
 136 static void cvm_oct_free_hw_memory(int pool, int size, int elements)
 137 {
 138         char *memory;
 139         char *fpa;
 140
 141         do {
 142                 fpa = cvmx_fpa_alloc(pool);
 143                 if (fpa) {
 144                         elements--;
 145                         fpa = (char *)phys_to_virt(cvmx_ptr_to_phys(fpa));
 146                         memory = *((char **)fpa - 1);
 147                         kfree(memory);
 148                 }
 149         } while (fpa);
 150
 151         if (elements < 0)
 152                 pr_warn("Freeing of pool %u had too many buffers (%d)\n",
 153                         pool, elements);
 154         else if (elements > 0)
 155                 pr_warn("Warning: Freeing of pool %u is missing %d buffers\n",
 156                         pool, elements);
 157 }
 158
 159 int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
 160 {
 161         int freed;
 162
 163         if (pool == CVMX_FPA_PACKET_POOL)
 164                 freed = cvm_oct_fill_hw_skbuff(pool, size, elements);
 165         else
 166                 freed = cvm_oct_fill_hw_memory(pool, size, elements);
 167         return freed;
 168 }
 169
 170 void cvm_oct_mem_empty_fpa(int pool, int size, int elements)
 171 {
 172         if (pool == CVMX_FPA_PACKET_POOL)
 173                 cvm_oct_free_hw_skbuff(pool, size, elements);
 174         else
 175                 cvm_oct_free_hw_memory(pool, size, elements);
 176 }