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         while (freed) {
  50
  51                 struct sk_buff *skb = dev_alloc_skb(size + 256);
  52                 if (unlikely(skb == NULL))
  53                         break;
  54                 skb_reserve(skb, 256 - (((unsigned long)skb->data) & 0x7f));
  55                 *(struct sk_buff **)(skb->data - sizeof(void *)) = skb;
  56                 cvmx_fpa_free(skb->data, pool, DONT_WRITEBACK(size / 128));
  57                 freed--;
  58         }
  59         return elements - freed;
  60 }
  61
  62 /**
  63  * cvm_oct_free_hw_skbuff- free hardware pool skbuffs
  64  * @pool:     Pool to allocate an skbuff for
  65  * @size:     Size of the buffer needed for the pool
  66  * @elements: Number of buffers to allocate
  67  */
  68 static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
  69 {
  70         char *memory;
  71
  72         do {
  73                 memory = cvmx_fpa_alloc(pool);
  74                 if (memory) {
  75                         struct sk_buff *skb =
  76                             *(struct sk_buff **)(memory - sizeof(void *));
  77                         elements--;
  78                         dev_kfree_skb(skb);
  79                 }
  80         } while (memory);
  81
  82         if (elements < 0)
  83                 pr_warn("Freeing of pool %u had too many skbuffs (%d)\n",
  84                      pool, elements);
  85         else if (elements > 0)
  86                 pr_warn("Freeing of pool %u is missing %d skbuffs\n",
  87                        pool, elements);
  88 }
  89
  90 /**
  91  * cvm_oct_fill_hw_memory - fill a hardware pool with memory.
  92  * @pool:     Pool to populate
  93  * @size:     Size of each buffer in the pool
  94  * @elements: Number of buffers to allocate
  95  *
  96  * Returns the actual number of buffers allocated.
  97  */
  98 static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
  99 {
 100         char *memory;
 101         char *fpa;
 102         int freed = elements;
 103
 104         while (freed) {
 105                 /*
 106                  * FPA memory must be 128 byte aligned.  Since we are
 107                  * aligning we need to save the original pointer so we
 108                  * can feed it to kfree when the memory is returned to
 109                  * the kernel.
 110                  *
 111                  * We allocate an extra 256 bytes to allow for
 112                  * alignment and space for the original pointer saved
 113                  * just before the block.
 114                  */
 115                 memory = kmalloc(size + 256, GFP_ATOMIC);
 116                 if (unlikely(memory == NULL)) {
 117                         pr_warn("Unable to allocate %u bytes for FPA pool %d\n",
 118                                    elements * size, pool);
 119                         break;
 120                 }
 121                 fpa = (char *)(((unsigned long)memory + 256) & ~0x7fUL);
 122                 *((char **)fpa - 1) = memory;
 123                 cvmx_fpa_free(fpa, pool, 0);
 124                 freed--;
 125         }
 126         return elements - freed;
 127 }
 128
 129 /**
 130  * cvm_oct_free_hw_memory - Free memory allocated by cvm_oct_fill_hw_memory
 131  * @pool:     FPA pool to free
 132  * @size:     Size of each buffer in the pool
 133  * @elements: Number of buffers that should be in the pool
 134  */
 135 static void cvm_oct_free_hw_memory(int pool, int size, int elements)
 136 {
 137         char *memory;
 138         char *fpa;
 139         do {
 140                 fpa = cvmx_fpa_alloc(pool);
 141                 if (fpa) {
 142                         elements--;
 143                         fpa = (char *)phys_to_virt(cvmx_ptr_to_phys(fpa));
 144                         memory = *((char **)fpa - 1);
 145                         kfree(memory);
 146                 }
 147         } while (fpa);
 148
 149         if (elements < 0)
 150                 pr_warn("Freeing of pool %u had too many buffers (%d)\n",
 151                         pool, elements);
 152         else if (elements > 0)
 153                 pr_warn("Warning: Freeing of pool %u is missing %d buffers\n",
 154                         pool, elements);
 155 }
 156
 157 int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
 158 {
 159         int freed;
 160         if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
 161                 freed = cvm_oct_fill_hw_skbuff(pool, size, elements);
 162         else
 163                 freed = cvm_oct_fill_hw_memory(pool, size, elements);
 164         return freed;
 165 }
 166
 167 void cvm_oct_mem_empty_fpa(int pool, int size, int elements)
 168 {
 169         if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
 170                 cvm_oct_free_hw_skbuff(pool, size, elements);
 171         else
 172                 cvm_oct_free_hw_memory(pool, size, elements);
 173 }