Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2022 Rockchip Electronics Co. Ltd.
 */
 
#include <linux/dma-buf.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/proc_fs.h>
#include <linux/scatterlist.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
 
#define K(size) ((unsigned long)((size) >> 10))
static struct device *dmabuf_dev;
 
static void rk_dmabuf_dump_empty_sgt(struct dma_buf *dmabuf, void *private)
{
<------>struct dma_buf_attachment *a;
<------>struct seq_file *s = private;
<------>struct scatterlist *sg;
<------>struct sg_table *sgt;
<------>phys_addr_t end, len;
<------>int i;
 
<------>a = dma_buf_attach(dmabuf, dmabuf_dev);
<------>if (IS_ERR(a))
<------><------>return;
 
<------>sgt = dma_buf_map_attachment(a, DMA_BIDIRECTIONAL);
<------>if (IS_ERR(sgt)) {
<------><------>dma_buf_detach(dmabuf, a);
<------><------>return;
<------>}
 
<------>for_each_sgtable_sg(sgt, sg, i) {
<------><------>end = sg->dma_address + sg->length - 1;
<------><------>len = sg->length;
<------><------>if (i)
<------><------><------>seq_printf(s, "%65s", " ");
<------><------>else
<------><------><------>seq_printf(s, "%px %-16.16s %-16.16s %10lu KiB",
<------><------><------><------>   dmabuf, dmabuf->name,
<------><------><------><------>   dmabuf->exp_name, K(dmabuf->size));
<------><------>seq_printf(s, "%4d: %pa..%pa (%10lu %s)\n", i,
<------><------><------>   &sg->dma_address, &end,
<------><------><------>   (len >> 10) ? (K(len)) : (unsigned long)len,
<------><------><------>   (len >> 10) ? "KiB" : "Bytes");
<------>}
<------>dma_buf_unmap_attachment(a, sgt, DMA_BIDIRECTIONAL);
<------>dma_buf_detach(dmabuf, a);
}
 
static void rk_dmabuf_dump_sgt(const struct dma_buf *dmabuf, void *private)
{
<------>struct seq_file *s = private;
<------>struct scatterlist *sg;
<------>struct dma_buf_attachment *a, *t;
<------>phys_addr_t end, len;
<------>int i;
 
<------>list_for_each_entry_safe(a, t, &dmabuf->attachments, node) {
<------><------>if (!a->sgt)
<------><------><------>continue;
<------><------>for_each_sgtable_sg(a->sgt, sg, i) {
<------><------><------>end = sg->dma_address + sg->length - 1;
<------><------><------>len = sg->length;
<------><------><------>if (i)
<------><------><------><------>seq_printf(s, "%65s", " ");
<------><------><------>else
<------><------><------><------>seq_printf(s, "%px %-16.16s %-16.16s %10lu KiB",
<------><------><------><------><------>   dmabuf, dmabuf->name,
<------><------><------><------><------>   dmabuf->exp_name, K(dmabuf->size));
<------><------><------>seq_printf(s, "%4d: %pa..%pa (%10lu %s)\n", i,
<------><------><------><------>   &sg->dma_address, &end,
<------><------><------><------>   (len >> 10) ? (K(len)) : (unsigned long)len,
<------><------><------><------>   (len >> 10) ? "KiB" : "Bytes");
<------><------>}
<------><------>return;
<------>}
<------>/* Try to attach and map the dmabufs without sgt. */
<------>if (IS_ENABLED(CONFIG_DMABUF_DEBUG_ADVANCED)) {
<------><------>struct dma_buf *dbuf = (struct dma_buf *)dmabuf;
 
<------><------>get_dma_buf(dbuf);
<------><------>rk_dmabuf_dump_empty_sgt(dbuf, s);
<------><------>dma_buf_put(dbuf);
<------>}
}
 
static int rk_dmabuf_cb(const struct dma_buf *dmabuf, void *private)
{
<------>struct seq_file *s = private;
 
<------>rk_dmabuf_dump_sgt(dmabuf, s);
 
<------>return 0;
}
 
static int rk_dmabuf_cb3(const struct dma_buf *dmabuf, void *private)
{
<------>struct seq_file *s = private;
<------>struct dma_buf_attachment *a, *t;
 
<------>seq_printf(s, "%px %-16.16s %-16.16s %10lu KiB",
<------><------>   dmabuf, dmabuf->name,
<------><------>   dmabuf->exp_name, K(dmabuf->size));
<------>list_for_each_entry_safe(a, t, &dmabuf->attachments, node) {
<------><------>seq_printf(s, " %s", dev_name(a->dev));
<------>}
<------>seq_puts(s, "\n");
 
<------>return 0;
}
 
static int rk_dmabuf_sgt_show(struct seq_file *s, void *v)
{
<------>seq_printf(s, "%16s %-16s %-16s %14s %8s\n\n",
<------><------>   "DMABUF", "NAME", "EXPORT", "SIZE:KiB", "SGLIST");
 
<------>return get_each_dmabuf(rk_dmabuf_cb, s);
}
 
static int rk_dmabuf_dev_show(struct seq_file *s, void *v)
{
<------>seq_printf(s, "%16s %-16s %-16s %14s %8s\n\n",
<------><------>   "DMABUF", "NAME", "EXPORT", "SIZE:KiB", "AttachedDevices");
 
<------>return get_each_dmabuf(rk_dmabuf_cb3, s);
}
 
static int rk_dmabuf_size_show(struct seq_file *s, void *v)
{
<------>seq_printf(s, "Total: %lu KiB\n", K(dma_buf_get_total_size()));
 
<------>return 0;
}
 
static int rk_dmabuf_peak_show(struct seq_file *s, void *v)
{
<------>seq_printf(s, "Peak: %lu MiB\n", K(K(dma_buf_get_peak_size())));
 
<------>return 0;
}
 
static ssize_t rk_dmabuf_peak_write(struct file *file,
<------><------><------><------>    const char __user *buffer,
<------><------><------><------>    size_t count, loff_t *ppos)
{
<------>char c;
<------>int rc;
 
<------>rc = get_user(c, buffer);
<------>if (rc)
<------><------>return rc;
 
<------>if (c != '0')
<------><------>return -EINVAL;
 
<------>dma_buf_reset_peak_size();
 
<------>return count;
}
 
static int rk_dmabuf_peak_open(struct inode *inode, struct file *file)
{
<------>return single_open(file, rk_dmabuf_peak_show, NULL);
}
 
static const struct proc_ops rk_dmabuf_peak_ops = {
<------>.proc_open	= rk_dmabuf_peak_open,
<------>.proc_read	= seq_read,
<------>.proc_lseek	= seq_lseek,
<------>.proc_release	= single_release,
<------>.proc_write	= rk_dmabuf_peak_write,
};
 
static int __init rk_dmabuf_init(void)
{
<------>struct platform_device *pdev;
<------>struct platform_device_info dev_info = {
<------><------>.name		= "dmabuf",
<------><------>.id		= PLATFORM_DEVID_NONE,
<------><------>.dma_mask	= DMA_BIT_MASK(64),
<------>};
<------>struct proc_dir_entry *root = proc_mkdir("rk_dmabuf", NULL);
 
<------>pdev = platform_device_register_full(&dev_info);
<------>dma_set_max_seg_size(&pdev->dev, (unsigned int)DMA_BIT_MASK(64));
<------>dmabuf_dev = pdev ? &pdev->dev : NULL;
 
<------>proc_create_single("sgt", 0, root, rk_dmabuf_sgt_show);
<------>proc_create_single("dev", 0, root, rk_dmabuf_dev_show);
<------>proc_create_single("size", 0, root, rk_dmabuf_size_show);
<------>proc_create("peak", 0644, root, &rk_dmabuf_peak_ops);
 
<------>return 0;
}
late_initcall_sync(rk_dmabuf_init);
 
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jianqun Xu <jay.xu@rock-chips.com>");
MODULE_DESCRIPTION("ROCKCHIP DMABUF Driver");
MODULE_ALIAS("platform:rk-dmabuf");