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-defines.h"
  34
  35 #include <asm/octeon/cvmx-fpa.h>
  36
  37 /**
  38  * cvm_oct_fill_hw_skbuff - fill the supplied hardware pool with skbuffs
  39  * @pool:     Pool to allocate an skbuff for
  40  * @size:     Size of the buffer needed for the pool
  41  * @elements: Number of buffers to allocate
  42  *
  43  * Returns the actual number of buffers allocated.
  44  */
  45 static int cvm_oct_fill_hw_skbuff(int pool, int size, int elements)
  46 {
  47         int freed = elements;
  48         while (freed) {
  49
  50                 struct sk_buff *skb = dev_alloc_skb(size + 256);
  51                 if (unlikely(skb == NULL))
  52                         break;
  53                 skb_reserve(skb, 256 - (((unsigned long)skb->data) & 0x7f));
  54                 *(struct sk_buff **)(skb->data - sizeof(void *)) = skb;
  55                 cvmx_fpa_free(skb->data, pool, DONT_WRITEBACK(size / 128));
  56                 freed--;
  57         }
  58         return elements - freed;
  59 }
  60
  61 /**
  62  * cvm_oct_free_hw_skbuff- free hardware pool skbuffs
  63  * @pool:     Pool to allocate an skbuff for
  64  * @size:     Size of the buffer needed for the pool
  65  * @elements: Number of buffers to allocate
  66  */
  67 static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
  68 {
  69         char *memory;
  70
  71         do {
  72                 memory = cvmx_fpa_alloc(pool);
  73                 if (memory) {
  74                         struct sk_buff *skb =
  75                             *(struct sk_buff **)(memory - sizeof(void *));
  76                         elements--;
  77                         dev_kfree_skb(skb);
  78                 }
  79         } while (memory);
  80
  81         if (elements < 0)
  82                 pr_warning("Freeing of pool %u had too many skbuffs (%d)\n",
  83                      pool, elements);
  84         else if (elements > 0)
  85                 pr_warning("Freeing of pool %u is missing %d skbuffs\n",
  86                        pool, elements);
  87 }
  88
  89 /**
  90  * cvm_oct_fill_hw_memory - fill a hardware pool with memory.
  91  * @pool:     Pool to populate
  92  * @size:     Size of each buffer in the pool
  93  * @elements: Number of buffers to allocate
  94  *
  95  * Returns the actual number of buffers allocated.
  96  */
  97 static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
  98 {
  99         char *memory;
 100         char *fpa;
 101         int freed = elements;
 102
 103         while (freed) {
 104                 /*
 105                  * FPA memory must be 128 byte aligned.  Since we are
 106                  * aligning we need to save the original pointer so we
 107                  * can feed it to kfree when the memory is returned to
 108                  * the kernel.
 109                  *
 110                  * We allocate an extra 256 bytes to allow for
 111                  * alignment and space for the original pointer saved
 112                  * just before the block.
 113                  */
 114                 memory = kmalloc(size + 256, GFP_ATOMIC);
 115                 if (unlikely(memory == NULL)) {
 116                         pr_warning("Unable to allocate %u bytes for FPA pool %d\n",
 117                                    elements * size, pool);
 118                         break;
 119                 }
 120                 fpa = (char *)(((unsigned long)memory + 256) & ~0x7fUL);
 121                 *((char **)fpa - 1) = memory;
 122                 cvmx_fpa_free(fpa, pool, 0);
 123                 freed--;
 124         }
 125         return elements - freed;
 126 }
 127
 128 /**
 129  * cvm_oct_free_hw_memory - Free memory allocated by cvm_oct_fill_hw_memory
 130  * @pool:     FPA pool to free
 131  * @size:     Size of each buffer in the pool
 132  * @elements: Number of buffers that should be in the pool
 133  */
 134 static void cvm_oct_free_hw_memory(int pool, int size, int elements)
 135 {
 136         char *memory;
 137         char *fpa;
 138         do {
 139                 fpa = cvmx_fpa_alloc(pool);
 140                 if (fpa) {
 141                         elements--;
 142                         fpa = (char *)phys_to_virt(cvmx_ptr_to_phys(fpa));
 143                         memory = *((char **)fpa - 1);
 144                         kfree(memory);
 145                 }
 146         } while (fpa);
 147
 148         if (elements < 0)
 149                 pr_warning("Freeing of pool %u had too many buffers (%d)\n",
 150                         pool, elements);
 151         else if (elements > 0)
 152                 pr_warning("Warning: Freeing of pool %u is missing %d buffers\n",
 153                         pool, elements);
 154 }
 155
 156 int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
 157 {
 158         int freed;
 159         if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
 160                 freed = cvm_oct_fill_hw_skbuff(pool, size, elements);
 161         else
 162                 freed = cvm_oct_fill_hw_memory(pool, size, elements);
 163         return freed;
 164 }
 165
 166 void cvm_oct_mem_empty_fpa(int pool, int size, int elements)
 167 {
 168         if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
 169                 cvm_oct_free_hw_skbuff(pool, size, elements);
 170         else
 171                 cvm_oct_free_hw_memory(pool, size, elements);
 172 }