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| author | Rob Herring (Arm) <robh@kernel.org> | 2026-08-31 14:43:51 -0500 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2026-09-13 18:17:31 -0700 |
| commit | 55fc280e951ab2b39f3dcb640edc1b1eebc6d173 (patch) | |
| tree | f0b5f37b42fc13b9908a31b657c646b024231cdd /drivers/firmware/efi/ovmf-debug-log.c | |
| download | linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.tar.gz linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.zip | |
Input: tsc2007 - read "ti,poll-period" as u32grafted
The "ti,poll-period" property is documented as a normal uint32 cell.
The driver used a u64 helper, which makes the helper type disagree with
the schema even though the stored value is still small.
Read "ti,poll-period" with the u32 helper matching the documented DT
cell size.
Assisted-by: Codex:gpt-5-5
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20260831194352.1185860-1-robh@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/firmware/efi/ovmf-debug-log.c')
| -rw-r--r-- | drivers/firmware/efi/ovmf-debug-log.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/firmware/efi/ovmf-debug-log.c b/drivers/firmware/efi/ovmf-debug-log.c new file mode 100644 index 000000000..5b2471ffa --- /dev/null +++ b/drivers/firmware/efi/ovmf-debug-log.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/efi.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kobject.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sysfs.h> + +#define OVMF_DEBUG_LOG_MAGIC1 0x3167646d666d766f // "ovmfmdg1" +#define OVMF_DEBUG_LOG_MAGIC2 0x3267646d666d766f // "ovmfmdg2" + +struct ovmf_debug_log_header { + u64 magic1; + u64 magic2; + u64 hdr_size; + u64 log_size; + u64 lock; // edk2 spinlock + u64 head_off; + u64 tail_off; + u64 truncated; + u8 fw_version[128]; +}; + +static struct ovmf_debug_log_header *hdr; +static u8 *logbuf; +static u64 logbufsize; + +static ssize_t ovmf_log_read(struct file *filp, struct kobject *kobj, + const struct bin_attribute *attr, char *buf, + loff_t offset, size_t count) +{ + u64 start, end; + + start = hdr->head_off + offset; + if (hdr->head_off > hdr->tail_off && start >= hdr->log_size) + start -= hdr->log_size; + + end = start + count; + if (start > hdr->tail_off) { + if (end > hdr->log_size) + end = hdr->log_size; + } else { + if (end > hdr->tail_off) + end = hdr->tail_off; + } + + if (start > logbufsize || end > logbufsize) + return 0; + if (start >= end) + return 0; + + memcpy(buf, logbuf + start, end - start); + return end - start; +} + +static struct bin_attribute ovmf_log_bin_attr = { + .attr = { + .name = "ovmf_debug_log", + .mode = 0444, + }, + .read = ovmf_log_read, +}; + +int __init ovmf_log_probe(unsigned long ovmf_debug_log_table) +{ + int ret = -EINVAL; + u64 size; + + /* map + verify header */ + hdr = memremap(ovmf_debug_log_table, sizeof(*hdr), MEMREMAP_WB); + if (!hdr) { + pr_err("OVMF debug log: header map failed\n"); + return -EINVAL; + } + + if (hdr->magic1 != OVMF_DEBUG_LOG_MAGIC1 || + hdr->magic2 != OVMF_DEBUG_LOG_MAGIC2) { + printk(KERN_ERR "OVMF debug log: magic mismatch\n"); + goto err_unmap; + } + + size = hdr->hdr_size + hdr->log_size; + pr_info("OVMF debug log: firmware version: \"%s\"\n", hdr->fw_version); + pr_info("OVMF debug log: buffer size: %lluk\n", size / 1024); + + /* map complete log buffer */ + memunmap(hdr); + hdr = memremap(ovmf_debug_log_table, size, MEMREMAP_WB); + if (!hdr) { + pr_err("OVMF debug log: buffer map failed\n"); + return -EINVAL; + } + logbuf = (void *)hdr + hdr->hdr_size; + logbufsize = hdr->log_size; + + ovmf_log_bin_attr.size = size; + ret = sysfs_create_bin_file(efi_kobj, &ovmf_log_bin_attr); + if (ret != 0) { + pr_err("OVMF debug log: sysfs register failed\n"); + goto err_unmap; + } + + return 0; + +err_unmap: + memunmap(hdr); + return ret; +} |
