Sec S3c2443x Test B D Driver Apr 2026

/* 1. Acquire memory region */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); testbd->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(testbd->base)) return PTR_ERR(testbd->base);

During stress runs, the driver logs timestamps to /sys/kernel/debug/sec_testbd/stress_log for offline analysis. | Test | Throughput (DMA) | Latency (Crypto) | Power (mW) | |------|------------------|------------------|------------| | 1 GiB secure copy | 1.84 GB/s | – | 120 | | AES‑256‑ECB (256 MiB) | – | 3.2 µs/KB | 95 | | SHA‑256 (1 GiB) | – | 1.1 µs/KB | 88 | | Stress mode 0 (10 k iter) | 0.9 GB/s (average) | – | 130 |

The Sec S3c2443x Test B D Driver is a reference implementation of a low‑level device driver for the Sec S3c2443x series of System‑on‑Chip (SoC) peripherals. It is primarily used in embedded Linux environments to validate the functionality of the “Test B D” hardware block, which provides a programmable interface for secure data handling, cryptographic acceleration, and DMA‑based I/O. Sec S3c2443x Test B D Driver

struct sec_testbd_crypto_req __u32 algo; /* SEC_ALGO_AES256, SEC_ALGO_SHA256, etc. */ __u32 mode; /* ENCRYPT, DECRYPT, HASH */ __u64 key_addr; /* Physical address of key material */ __u64 src_addr; /* Input data buffer */ __u64 dst_addr; /* Output buffer (or NULL for hash) */ __u32 length; /* Data length */ ; The driver programs the CE registers, starts the operation, and returns the status. The CE can process up to 64 KB per command; larger payloads are automatically split. The driver provides a special ioctl SEC_TESTBD_IOCTL_STRESS that configures the internal test logic:

/* 4. Register char device */ ret = alloc_chrdev_region(&dev_num, 0, 1, "sec_testbd"); if (ret) return ret; cdev_init(&testbd->cdev, &sec_testbd_fops); testbd->cdev.owner = THIS_MODULE; ret = cdev_add(&testbd->cdev, dev_num, 1); if (ret) goto err_unregister; It is primarily used in embedded Linux environments

# Perform a secure DMA copy (user‑space program) ./testbd_tool --dma --src 0x80000000 --dst 0x81000000 --len 1048576 --encrypt

struct resource *res; int ret;

| Parameter | Meaning | |-----------|---------| | mode | 0 = buffer‑overflow test, 1 = timing jitter, 2 = fault‑injection | | iterations | Number of stress cycles (max 10 000) | | seed | Pseudo‑random seed for pattern generation |

err_unregister: unregister_chrdev_region(dev_num, 1); return ret; The CE can process up to 64 KB

* * All the Notes in this blog, are referred from Tamil Nadu State Board Books and Samacheer Kalvi Books. Kindly check with the original Tamil Nadu state board books and Ncert Books.