drivers/staging/octeon/ethernet-mem.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * This file is based on code from OCTEON SDK by Cavium Networks.
   4  *
   5  * Copyright (c) 2003-2010 Cavium Networks
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/slab.h>
  11
  12 #include <asm/octeon/octeon.h>
  13
  14 #include "ethernet-mem.h"
  15 #include "ethernet-defines.h"
  16
  17 #include <asm/octeon/cvmx-fpa.h>
  18
  19 /**
  20  * cvm_oct_fill_hw_skbuff - fill the supplied hardware pool with skbuffs
  21  * @pool:     Pool to allocate an skbuff for
  22  * @size:     Size of the buffer needed for the pool
  23  * @elements: Number of buffers to allocate
  24  *
  25  * Returns the actual number of buffers allocated.
  26  */
  27 static int cvm_oct_fill_hw_skbuff(int pool, int size, int elements)
  28 {
  29         int freed = elements;
  30
  31         while (freed) {
  32                 struct sk_buff *skb = dev_alloc_skb(size + 256);
  33
  34                 if (unlikely(!skb))
  35                         break;
  36                 skb_reserve(skb, 256 - (((unsigned long)skb->data) & 0x7f));
  37                 *(struct sk_buff **)(skb->data - sizeof(void *)) = skb;
  38                 cvmx_fpa_free(skb->data, pool, size / 128);
  39                 freed--;
  40         }
  41         return elements - freed;
  42 }
  43
  44 /**
  45  * cvm_oct_free_hw_skbuff- free hardware pool skbuffs
  46  * @pool:     Pool to allocate an skbuff for
  47  * @size:     Size of the buffer needed for the pool
  48  * @elements: Number of buffers to allocate
  49  */
  50 static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
  51 {
  52         char *memory;
  53
  54         do {
  55                 memory = cvmx_fpa_alloc(pool);
  56                 if (memory) {
  57                         struct sk_buff *skb =
  58                             *(struct sk_buff **)(memory - sizeof(void *));
  59                         elements--;
  60                         dev_kfree_skb(skb);
  61                 }
  62         } while (memory);
  63
  64         if (elements < 0)
  65                 pr_warn("Freeing of pool %u had too many skbuffs (%d)\n",
  66                         pool, elements);
  67         else if (elements > 0)
  68                 pr_warn("Freeing of pool %u is missing %d skbuffs\n",
  69                         pool, elements);
  70 }
  71
  72 /**
  73  * cvm_oct_fill_hw_memory - fill a hardware pool with memory.
  74  * @pool:     Pool to populate
  75  * @size:     Size of each buffer in the pool
  76  * @elements: Number of buffers to allocate
  77  *
  78  * Returns the actual number of buffers allocated.
  79  */
  80 static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
  81 {
  82         char *memory;
  83         char *fpa;
  84         int freed = elements;
  85
  86         while (freed) {
  87                 /*
  88                  * FPA memory must be 128 byte aligned.  Since we are
  89                  * aligning we need to save the original pointer so we
  90                  * can feed it to kfree when the memory is returned to
  91                  * the kernel.
  92                  *
  93                  * We allocate an extra 256 bytes to allow for
  94                  * alignment and space for the original pointer saved
  95                  * just before the block.
  96                  */
  97                 memory = kmalloc(size + 256, GFP_ATOMIC);
  98                 if (unlikely(!memory)) {
  99                         pr_warn("Unable to allocate %u bytes for FPA pool %d\n",
 100                                 elements * size, pool);
 101                         break;
 102                 }
 103                 fpa = (char *)(((unsigned long)memory + 256) & ~0x7fUL);
 104                 *((char **)fpa - 1) = memory;
 105                 cvmx_fpa_free(fpa, pool, 0);
 106                 freed--;
 107         }
 108         return elements - freed;
 109 }
 110
 111 /**
 112  * cvm_oct_free_hw_memory - Free memory allocated by cvm_oct_fill_hw_memory
 113  * @pool:     FPA pool to free
 114  * @size:     Size of each buffer in the pool
 115  * @elements: Number of buffers that should be in the pool
 116  */
 117 static void cvm_oct_free_hw_memory(int pool, int size, int elements)
 118 {
 119         char *memory;
 120         char *fpa;
 121
 122         do {
 123                 fpa = cvmx_fpa_alloc(pool);
 124                 if (fpa) {
 125                         elements--;
 126                         fpa = (char *)phys_to_virt(cvmx_ptr_to_phys(fpa));
 127                         memory = *((char **)fpa - 1);
 128                         kfree(memory);
 129                 }
 130         } while (fpa);
 131
 132         if (elements < 0)
 133                 pr_warn("Freeing of pool %u had too many buffers (%d)\n",
 134                         pool, elements);
 135         else if (elements > 0)
 136                 pr_warn("Warning: Freeing of pool %u is missing %d buffers\n",
 137                         pool, elements);
 138 }
 139
 140 int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
 141 {
 142         int freed;
 143
 144         if (pool == CVMX_FPA_PACKET_POOL)
 145                 freed = cvm_oct_fill_hw_skbuff(pool, size, elements);
 146         else
 147                 freed = cvm_oct_fill_hw_memory(pool, size, elements);
 148         return freed;
 149 }
 150
 151 void cvm_oct_mem_empty_fpa(int pool, int size, int elements)
 152 {
 153         if (pool == CVMX_FPA_PACKET_POOL)
 154                 cvm_oct_free_hw_skbuff(pool, size, elements);
 155         else
 156                 cvm_oct_free_hw_memory(pool, size, elements);
 157 }