On Mon, Jul 13, 2020 at 03:29:26PM +0200, Alexandre Bailon wrote: > Currently, this local RAM is not accessible from the CPU. > If the CPU tries to access it, then the CPU will hang. > > Remoteproc may try to use it when it load a firmware > that has some sections in the local RAM. > This workarounds the issue by skiping this section. > > Signed-off-by: Alexandre Bailon <[email protected]> > --- > drivers/remoteproc/mtk_apu_rproc.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/remoteproc/mtk_apu_rproc.c > b/drivers/remoteproc/mtk_apu_rproc.c > index 565b3adca5de..e16d3258a785 100644 > --- a/drivers/remoteproc/mtk_apu_rproc.c > +++ b/drivers/remoteproc/mtk_apu_rproc.c > @@ -57,6 +57,9 @@ > #define CORE_DEFAULT2_SPIDEN BIT(0) > #define CORE_XTENSA_ALTRESETVEC (0x000001F8) > > +#define DRAM0_START (0x7ff00000) > +#define IRAM0_END (0x7ff80000) > + > struct mtk_vpu_rproc { > struct device *dev; > struct rproc *rproc; > @@ -139,6 +142,7 @@ static void mtk_vpu_rproc_kick(struct rproc *rproc, int > vqid) > > int mtk_vpu_elf_sanity_check(struct rproc *rproc, const struct firmware *fw) > { > + struct mtk_vpu_rproc *vpu_rproc = rproc->priv; > const u8 *elf_data = fw->data; > struct elf32_hdr *ehdr; > struct elf32_phdr *phdr; > @@ -156,6 +160,16 @@ int mtk_vpu_elf_sanity_check(struct rproc *rproc, const > struct firmware *fw) > /* Remove empty PT_LOAD section */ > if (phdr->p_type == PT_LOAD && !phdr->p_paddr) > phdr->p_type = PT_NULL; > + /* > + * Workaround: Currently, the CPU can't access to the APU > + * local RAM. This removes the local RAM section from the > + * firmware. Please note that may cause some issues. > + */ > + if (phdr->p_paddr >= DRAM0_START && phdr->p_paddr < IRAM0_END) { > + dev_warn_once(vpu_rproc->dev, > + "Skipping the APU local RAM section\n"); > + phdr->p_type = PT_NULL;
We can't selectively decide to not load sections of a program due to a platform driver shortcoming. Either a real solution is found or booting the remote processor is interrupted, with a strong incline toward the former. I guess you're dealing with tightly coupled memory or on-chip RAM areas - both are accessed on other platform using ioremap_wc() or devm_ioremap_wc(). You might want to try doing what Suman has done in this patchset [1], with specific attention to TCMs and SRAM. Thanks, Mathieu [1]. https://patchwork.kernel.org/project/linux-remoteproc/list/?series=310325 > + } > } > > return 0; > -- > 2.26.2 >
