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"Das U-Boot" Source Tree
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Bootmethod for extlinux boot using PXE (network boot)
4 *
5 * Copyright 2021 Google LLC
6 * Written by Simon Glass <sjg@chromium.org>
7 */
8
9#define LOG_CATEGORY UCLASS_BOOTSTD
10
11#include <bootdev.h>
12#include <bootflow.h>
13#include <bootmeth.h>
14#include <command.h>
15#include <dm.h>
16#include <extlinux.h>
17#include <fs.h>
18#include <log.h>
19#include <malloc.h>
20#include <mapmem.h>
21#include <mmc.h>
22#include <net.h>
23#include <pxe_utils.h>
24
25static int extlinux_pxe_getfile(struct pxe_context *ctx, const char *file_path,
26 char *file_addr, enum bootflow_img_t type,
27 ulong *sizep)
28{
29 struct extlinux_info *info = ctx->userdata;
30 ulong addr;
31 int ret;
32
33 addr = simple_strtoul(file_addr, NULL, 16);
34
35 /* Allow up to 1GB */
36 *sizep = 1 << 30;
37 ret = bootmeth_read_file(info->dev, info->bflow, file_path, addr,
38 type, sizep);
39 if (ret)
40 return log_msg_ret("read", ret);
41
42 return 0;
43}
44
45static int extlinux_pxe_check(struct udevice *dev, struct bootflow_iter *iter)
46{
47 int ret;
48
49 /* This only works on network devices */
50 ret = bootflow_iter_check_net(iter);
51 if (ret)
52 return log_msg_ret("net", ret);
53
54 if (iter->method_flags & BOOTFLOW_METHF_DHCP_ONLY)
55 return log_msg_ret("dhcp", -ENOTSUPP);
56
57 return 0;
58}
59
60static int extlinux_pxe_read_bootflow(struct udevice *dev,
61 struct bootflow *bflow)
62{
63 const char *addr_str;
64 char fname[200];
65 char *bootdir;
66 ulong addr;
67 ulong size;
68 char *buf;
69 int ret;
70
71 addr_str = env_get("pxefile_addr_r");
72 if (!addr_str)
73 return log_msg_ret("pxeb", -EPERM);
74 addr = simple_strtoul(addr_str, NULL, 16);
75
76 log_debug("calling pxe_get()\n");
77 ret = pxe_get(addr, &bootdir, &size, false);
78 log_debug("pxe_get() returned %d\n", ret);
79 if (ret)
80 return log_msg_ret("pxeb", ret);
81 bflow->size = size;
82
83 /* Use the directory of the dhcp bootdir as our subdir, if provided */
84 if (bootdir) {
85 const char *last_slash;
86 int path_len;
87
88 last_slash = strrchr(bootdir, '/');
89 if (last_slash) {
90 path_len = (last_slash - bootdir) + 1;
91 bflow->subdir = malloc(path_len + 1);
92 memcpy(bflow->subdir, bootdir, path_len);
93 bflow->subdir[path_len] = '\0';
94 }
95 }
96 snprintf(fname, sizeof(fname), "%s%s",
97 bflow->subdir ? bflow->subdir : "", EXTLINUX_FNAME);
98
99 bflow->fname = strdup(fname);
100 if (!bflow->fname)
101 return log_msg_ret("name", -ENOMEM);
102
103 bflow->state = BOOTFLOWST_READY;
104
105 /* Allocate the buffer, including the \0 byte added by get_pxe_file() */
106 buf = malloc(size + 1);
107 if (!buf)
108 return log_msg_ret("buf", -ENOMEM);
109 memcpy(buf, map_sysmem(addr, 0), size + 1);
110 bflow->buf = buf;
111
112 return 0;
113}
114
115static int extlinux_pxe_read_file(struct udevice *dev, struct bootflow *bflow,
116 const char *file_path, ulong addr,
117 enum bootflow_img_t type, ulong *sizep)
118{
119 char *tftp_argv[] = {"tftp", NULL, NULL, NULL};
120 struct pxe_context *ctx = dev_get_priv(dev);
121 char file_addr[17];
122 ulong size;
123 int ret;
124
125 sprintf(file_addr, "%lx", addr);
126 tftp_argv[1] = file_addr;
127 tftp_argv[2] = (void *)file_path;
128
129 if (do_tftpb(ctx->cmdtp, 0, 3, tftp_argv))
130 return -ENOENT;
131 ret = pxe_get_file_size(&size);
132 if (ret)
133 return log_msg_ret("tftp", ret);
134 if (size > *sizep)
135 return log_msg_ret("spc", -ENOSPC);
136 *sizep = size;
137
138 if (!bootflow_img_add(bflow, file_path, type, addr, size))
139 return log_msg_ret("pxi", -ENOMEM);
140
141 return 0;
142}
143
144static int extlinux_pxe_boot(struct udevice *dev, struct bootflow *bflow)
145{
146 struct pxe_context *ctx = dev_get_priv(dev);
147 struct cmd_tbl cmdtp = {}; /* dummy */
148 struct extlinux_info info;
149 ulong addr;
150 int ret;
151
152 addr = map_to_sysmem(bflow->buf);
153 info.dev = dev;
154 info.bflow = bflow;
155 info.cmdtp = &cmdtp;
156 ret = pxe_setup_ctx(ctx, &cmdtp, extlinux_pxe_getfile, &info, false,
157 bflow->subdir, false, false);
158 if (ret)
159 return log_msg_ret("ctx", -EINVAL);
160
161 ret = pxe_process(ctx, addr, false);
162 if (ret)
163 return log_msg_ret("bread", -EINVAL);
164
165 return 0;
166}
167
168static int extlinux_bootmeth_pxe_bind(struct udevice *dev)
169{
170 struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
171
172 plat->desc = IS_ENABLED(CONFIG_BOOTSTD_FULL) ?
173 "PXE boot from a network device" : "PXE";
174
175 return 0;
176}
177
178static struct bootmeth_ops extlinux_bootmeth_pxe_ops = {
179 .check = extlinux_pxe_check,
180 .read_bootflow = extlinux_pxe_read_bootflow,
181 .read_file = extlinux_pxe_read_file,
182 .boot = extlinux_pxe_boot,
183};
184
185static const struct udevice_id extlinux_bootmeth_pxe_ids[] = {
186 { .compatible = "u-boot,extlinux-pxe" },
187 { }
188};
189
190U_BOOT_DRIVER(bootmeth_zpxe) = {
191 .name = "bootmeth_pxe",
192 .id = UCLASS_BOOTMETH,
193 .of_match = extlinux_bootmeth_pxe_ids,
194 .ops = &extlinux_bootmeth_pxe_ops,
195 .bind = extlinux_bootmeth_pxe_bind,
196 .priv_auto = sizeof(struct pxe_context),
197};