drivers/gpu/drm/lima/lima_l2_cache.c

   1 // SPDX-License-Identifier: GPL-2.0 OR MIT
   2 /* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
   3
   4 #include <linux/iopoll.h>
   5 #include <linux/device.h>
   6
   7 #include "lima_device.h"
   8 #include "lima_l2_cache.h"
   9 #include "lima_regs.h"
  10
  11 #define l2_cache_write(reg, data) writel(data, ip->iomem + reg)
  12 #define l2_cache_read(reg) readl(ip->iomem + reg)
  13
  14 static int lima_l2_cache_wait_idle(struct lima_ip *ip)
  15 {
  16         struct lima_device *dev = ip->dev;
  17         int err;
  18         u32 v;
  19
  20         err = readl_poll_timeout(ip->iomem + LIMA_L2_CACHE_STATUS, v,
  21                                  !(v & LIMA_L2_CACHE_STATUS_COMMAND_BUSY),
  22                                  0, 1000);
  23         if (err) {
  24                 dev_err(dev->dev, "l2 cache wait command timeout\n");
  25                 return err;
  26         }
  27         return 0;
  28 }
  29
  30 int lima_l2_cache_flush(struct lima_ip *ip)
  31 {
  32         int ret;
  33
  34         spin_lock(&ip->data.lock);
  35         l2_cache_write(LIMA_L2_CACHE_COMMAND, LIMA_L2_CACHE_COMMAND_CLEAR_ALL);
  36         ret = lima_l2_cache_wait_idle(ip);
  37         spin_unlock(&ip->data.lock);
  38         return ret;
  39 }
  40
  41 int lima_l2_cache_init(struct lima_ip *ip)
  42 {
  43         int i, err;
  44         u32 size;
  45         struct lima_device *dev = ip->dev;
  46
  47         /* l2_cache2 only exists when one of PP4-7 present */
  48         if (ip->id == lima_ip_l2_cache2) {
  49                 for (i = lima_ip_pp4; i <= lima_ip_pp7; i++) {
  50                         if (dev->ip[i].present)
  51                                 break;
  52                 }
  53                 if (i > lima_ip_pp7)
  54                         return -ENODEV;
  55         }
  56
  57         spin_lock_init(&ip->data.lock);
  58
  59         size = l2_cache_read(LIMA_L2_CACHE_SIZE);
  60         dev_info(dev->dev, "l2 cache %uK, %u-way, %ubyte cache line, %ubit external bus\n",
  61                  1 << (((size >> 16) & 0xff) - 10),
  62                  1 << ((size >> 8) & 0xff),
  63                  1 << (size & 0xff),
  64                  1 << ((size >> 24) & 0xff));
  65
  66         err = lima_l2_cache_flush(ip);
  67         if (err)
  68                 return err;
  69
  70         l2_cache_write(LIMA_L2_CACHE_ENABLE,
  71                        LIMA_L2_CACHE_ENABLE_ACCESS|LIMA_L2_CACHE_ENABLE_READ_ALLOCATE);
  72         l2_cache_write(LIMA_L2_CACHE_MAX_READS, 0x1c);
  73
  74         return 0;
  75 }
  76
  77 void lima_l2_cache_fini(struct lima_ip *ip)
  78 {
  79
  80 }