1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3
4 btcx-risc.c
5
6 bt848/bt878/cx2388x risc code generator.
7
8 (c) 2000-03 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
9
10
11*/
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/pci.h>
18#include <linux/interrupt.h>
19#include <linux/videodev2.h>
20#include <linux/pgtable.h>
21#include <asm/page.h>
22
23#include "btcx-risc.h"
24
25static unsigned int btcx_debug;
26module_param(btcx_debug, int, 0644);
27MODULE_PARM_DESC(btcx_debug,"debug messages, default is 0 (no)");
28
29#define dprintk(fmt, arg...) do { \
30 if (btcx_debug) \
31 printk(KERN_DEBUG pr_fmt("%s: " fmt), \
32 __func__, ##arg); \
33} while (0)
34
35
36/* ---------------------------------------------------------- */
37/* allocate/free risc memory */
38
39static int memcnt;
40
41void btcx_riscmem_free(struct pci_dev *pci,
42 struct btcx_riscmem *risc)
43{
44 if (NULL == risc->cpu)
45 return;
46
47 memcnt--;
48 dprintk("btcx: riscmem free [%d] dma=%lx\n",
49 memcnt, (unsigned long)risc->dma);
50
51 dma_free_coherent(dev: &pci->dev, size: risc->size, cpu_addr: risc->cpu, dma_handle: risc->dma);
52 memset(risc,0,sizeof(*risc));
53}
54
55int btcx_riscmem_alloc(struct pci_dev *pci,
56 struct btcx_riscmem *risc,
57 unsigned int size)
58{
59 __le32 *cpu;
60 dma_addr_t dma = 0;
61
62 if (NULL != risc->cpu && risc->size < size)
63 btcx_riscmem_free(pci,risc);
64 if (NULL == risc->cpu) {
65 cpu = dma_alloc_coherent(dev: &pci->dev, size, dma_handle: &dma, GFP_KERNEL);
66 if (NULL == cpu)
67 return -ENOMEM;
68 risc->cpu = cpu;
69 risc->dma = dma;
70 risc->size = size;
71
72 memcnt++;
73 dprintk("btcx: riscmem alloc [%d] dma=%lx cpu=%p size=%d\n",
74 memcnt, (unsigned long)dma, cpu, size);
75 }
76 return 0;
77}
78

source code of linux/drivers/media/pci/bt8xx/btcx-risc.c