Le Tue, Sep 21, 2021 at 11:39:27PM +0200, Emmanuel Gil Peyrot a écrit : > This engine implements AES in CBC mode, using 128-bit keys only. It is > present on both the Wii and the Wii U, and is apparently identical in > both consoles. > > The hardware is capable of firing an interrupt when the operation is > done, but this driver currently uses a busy loop, I’m not too sure > whether it would be preferable to switch, nor how to achieve that. > > It also supports a mode where no operation is done, and thus could be > used as a DMA copy engine, but I don’t know how to expose that to the > kernel or whether it would even be useful. > > In my testing, on a Wii U, this driver reaches 80.7 MiB/s, while the > aes-generic driver only reaches 30.9 MiB/s, so it is a quite welcome > speedup. > > This driver was written based on reversed documentation, see: > https://wiibrew.org/wiki/Hardware/AES > > Signed-off-by: Emmanuel Gil Peyrot <linkmauve@xxxxxxxxxxxx> > Tested-by: Emmanuel Gil Peyrot <linkmauve@xxxxxxxxxxxx> # on Wii U [...] > +static int > +do_crypt(const void *src, void *dst, u32 len, u32 flags) > +{ > + u32 blocks = ((len >> 4) - 1) & AES_CTRL_BLOCK; > + u32 status; > + u32 counter = OP_TIMEOUT; > + u32 i; > + > + /* Flush out all of src, we can’t know whether any of it is in cache */ > + for (i = 0; i < len; i += 32) > + __asm__("dcbf 0, %0" : : "r" (src + i)); > + __asm__("sync" : : : "memory"); > + > + /* Set the addresses for DMA */ > + iowrite32be(virt_to_phys((void *)src), base + AES_SRC); > + iowrite32be(virt_to_phys(dst), base + AES_DEST); Hello Since you do DMA operation, I think you should use the DMA-API and call dma_map_xxx() This will prevent the use of __asm__ and virt_to_phys(). Regards
