On Thu, Apr 21, 2016 at 12:04:21PM +0100, Peter Griffin wrote:
> +static int
> +st_fdma_elf_sanity_check(struct st_fdma_dev *fdev, const struct firmware *fw)
> +{
> + const char *fw_name = fdev->fw_name;
> + struct elf32_hdr *ehdr;
> + char class;
> +
> + if (!fw) {
> + dev_err(fdev->dev, "failed to load %s\n", fw_name);
> + return -EINVAL;
> + }
> +
> + if (fw->size < sizeof(*ehdr)) {
> + dev_err(fdev->dev, "Image is too small\n");
> + return -EINVAL;
> + }
> +
> + ehdr = (struct elf32_hdr *)fw->data;
> +
> + /* We only support ELF32 at this point */
> + class = ehdr->e_ident[EI_CLASS];
> + if (class != ELFCLASS32) {
> + dev_err(fdev->dev, "Unsupported class: %d\n", class);
> + return -EINVAL;
> + }
> +
> + if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB) {
> + dev_err(fdev->dev, "Unsupported firmware endianness"
> + "(%d) expected (%d)\n", ehdr->e_ident[EI_DATA],
> + ELFDATA2LSB);
> + return -EINVAL;
> + }
> +
> + if (fw->size < ehdr->e_shoff + sizeof(struct elf32_shdr)) {
> + dev_err(fdev->dev, "Image is too small (%u)\n", fw->size);
> + return -EINVAL;
> + }
> +
> + if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
> + dev_err(fdev->dev, "Image is corrupted (bad magic)\n");
> + return -EINVAL;
> + }
> +
> + if (ehdr->e_phnum != fdev->drvdata->num_mem) {
> + dev_err(fdev->dev, "spurious nb of segments (%d) expected (%d)"
> + "\n", ehdr->e_phnum, fdev->drvdata->num_mem);
> + return -EINVAL;
> + }
> +
> + if (ehdr->e_type != ET_EXEC) {
> + dev_err(fdev->dev, "Unsupported ELF header type (%d) expected"
> + " (%d)\n", ehdr->e_type, ET_EXEC);
> + return -EINVAL;
> + }
> +
> + if (ehdr->e_machine != EM_SLIM) {
> + dev_err(fdev->dev, "Unsupported ELF header machine (%d) "
> + "expected (%d)\n", ehdr->e_machine, EM_SLIM);
> + return -EINVAL;
> + }
> + if (ehdr->e_phoff > fw->size) {
> + dev_err(fdev->dev, "Firmware size is too small\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int
> +st_fdma_elf_load_segments(struct st_fdma_dev *fdev, const struct firmware
> *fw)
> +{
> + struct device *dev = fdev->dev;
> + struct elf32_hdr *ehdr;
> + struct elf32_phdr *phdr;
> + int i, mem_loaded = 0;
> + const u8 *elf_data = fw->data;
> +
> + ehdr = (struct elf32_hdr *)elf_data;
> + phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff);
> +
> + /*
> + * go through the available ELF segments
> + * the program header's paddr member to contain device addresses.
> + * We then go through the physically contiguous memory regions which we
> + * allocated (and mapped) earlier on the probe,
> + * and "translate" device address to kernel addresses,
> + * so we can copy the segments where they are expected.
> + */
> + for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
> + u32 da = phdr->p_paddr;
> + u32 memsz = phdr->p_memsz;
> + u32 filesz = phdr->p_filesz;
> + u32 offset = phdr->p_offset;
> + void *dst;
> +
> + if (phdr->p_type != PT_LOAD)
> + continue;
> +
> + dev_dbg(dev, "phdr: type %d da %#x ofst:%#x memsz %#x filesz
> %#x\n",
> + phdr->p_type, da, offset, memsz, filesz);
> +
> + if (filesz > memsz) {
> + dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n",
> + filesz, memsz);
> + break;
> + }
> +
> + if (offset + filesz > fw->size) {
> + dev_err(dev, "truncated fw: need 0x%x avail 0x%zx\n",
> + offset + filesz, fw->size);
> + break;
> + }
> +
> + dst = st_fdma_seg_to_mem(fdev, da, memsz);
> + if (!dst) {
> + dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz);
> + break;
> + }
> +
> + if (phdr->p_filesz)
> + memcpy(dst, elf_data + phdr->p_offset, filesz);
> +
> + if (memsz > filesz)
> + memset(dst + filesz, 0, memsz - filesz);
> +
> + mem_loaded++;
> + }
> +
> + return (mem_loaded != fdev->drvdata->num_mem) ? -EIO : 0;
> +}
Above two seem to be generic code and should be moved to core, this way
other drivers using ELF firmware binaries can reuse...
> @@ -738,6 +925,15 @@ static int st_fdma_slave_config(struct dma_chan *chan,
> struct dma_slave_config *slave_cfg)
> {
> struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
> + int ret;
> +
> + if (!atomic_read(&fchan->fdev->fw_loaded)) {
> + ret = st_fdma_get_fw(fchan->fdev);
this seems quite an odd place to load firmware, can you explain why
--
~Vinod
