forked from openwrt/openwrt
-
Notifications
You must be signed in to change notification settings - Fork 4
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
qualcommax: add kernel cmdline replacement hack
Add kernel cmdline replacement hack to qualcommax. Now we can find and replace cmdline by setting bootargs-find-1, bootargs-replace-1, bootargs-exact-match-1 and bootargs-find-2, bootargs-replace-2, bootargs-exact-match-2 under the chosen node in the device tree. The goal of thie hack is to to add support for Linksys MX4300, a dual firmware AP. This device's default kernel command lines aren't compatiailbe with OpenWrt's UBI, so we leverage find and replace to dynamically patch the cmd from u-boot. Signed-off-by: Qiyuan Zhang <[email protected]>
- Loading branch information
Qiyuan Zhang
committed
Aug 4, 2024
1 parent
48bd543
commit 28a031f
Showing
2 changed files
with
98 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
87 changes: 87 additions & 0 deletions
87
target/linux/qualcommax/patches-6.6/0911-arm64-cmdline-replacement.patch
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,87 @@ | ||
| --- a/drivers/of/fdt.c | ||
| +++ b/drivers/of/fdt.c | ||
| @@ -1157,6 +1157,14 @@ int __init early_init_dt_scan_chosen(cha | ||
| const void *rng_seed; | ||
| const void *fdt = initial_boot_params; | ||
|
|
||
| + int i, cmd_len, f_len, r_len, offset, step; | ||
| + char *s_ptr, *l_end, *r_end, *cur_ptr, *end_ptr; | ||
| + const char *exact_match; | ||
| + const int bootargs_replace_num = 2; | ||
| + const char *bootargs_replace_props[2][3] = | ||
| + { {"bootargs-find-1", "bootargs-replace-1", "bootargs-exact-match-1"}, | ||
| + {"bootargs-find-2", "bootargs-replace-2", "bootargs-exact-match-2"} }; | ||
| + | ||
| node = fdt_path_offset(fdt, "/chosen"); | ||
| if (node < 0) | ||
| node = fdt_path_offset(fdt, "/chosen@0"); | ||
| @@ -1185,6 +1193,69 @@ int __init early_init_dt_scan_chosen(cha | ||
| p = of_get_flat_dt_prop(node, "bootargs", &l); | ||
| if (p != NULL && l > 0) | ||
| strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE)); | ||
| + | ||
| + for(i = 0; i < bootargs_replace_num; i++) { | ||
| + p = of_get_flat_dt_prop(node, bootargs_replace_props[i][0], &f_len); | ||
| + | ||
| + if (p == NULL || f_len == 0 ) | ||
| + continue; | ||
| + | ||
| + exact_match = of_get_flat_dt_prop(node, bootargs_replace_props[i][2], &l); | ||
| + | ||
| + if (exact_match != NULL && l > 0 && exact_match[0] == 'y') { | ||
| + if(strncmp(cmdline, p, r_len) == 0) | ||
| + s_ptr = cmdline; | ||
| + else | ||
| + s_ptr = NULL; | ||
| + } else { | ||
| + s_ptr = strstr(cmdline, p); | ||
| + } | ||
| + | ||
| + if(!s_ptr) | ||
| + continue; | ||
| + | ||
| + p = of_get_flat_dt_prop(node, bootargs_replace_props[i][1], &r_len); | ||
| + | ||
| + if (p == NULL || r_len == 0) | ||
| + continue; | ||
| + | ||
| + pr_info("Input kernel commad line: %s\n", cmdline); | ||
| + | ||
| + cmd_len = strlen(cmdline); | ||
| + | ||
| + if (cmd_len - f_len + r_len < COMMAND_LINE_SIZE) { | ||
| + | ||
| + pr_info("Replace kernel command line with %s\n", bootargs_replace_props[i][1]); | ||
| + | ||
| + offset = r_len - f_len; | ||
| + | ||
| + if (offset != 0) { | ||
| + l_end = s_ptr + f_len - 1; | ||
| + r_end = cmdline + cmd_len; | ||
| + | ||
| + if (offset > 0) { | ||
| + step = -1; | ||
| + cur_ptr = r_end; | ||
| + end_ptr = l_end + step; | ||
| + } else { | ||
| + step = 1; | ||
| + cur_ptr = l_end; | ||
| + end_ptr = r_end + step; | ||
| + } | ||
| + | ||
| + for (; cur_ptr != end_ptr; cur_ptr += step) | ||
| + *(cur_ptr + offset) = *cur_ptr; | ||
| + } | ||
| + | ||
| + strncpy(s_ptr, p, r_len - 1); | ||
| + | ||
| + pr_info("Kernel command line after replacement: %s\n", cmdline); | ||
| + } else { | ||
| + pr_err("Replace kernel command line with %s failed\n", bootargs_replace_props[i][1]); | ||
| + } | ||
| + | ||
| + } | ||
| + | ||
| p = of_get_flat_dt_prop(node, "bootargs-append", &l); | ||
| if (p != NULL && l > 0) | ||
| strlcat(cmdline, p, min_t(int, strlen(cmdline) + (int)l, COMMAND_LINE_SIZE)); |