From: Igor Opaniuk igor.opaniuk@toradex.com
i.MX 7's Cortex-M4 core can run from DDR and uses DDR memory for the rpmsg communication. Both use cases need a fixed location of memory reserved. For the rpmsg use case the reserved area needs to be in sync with the kernel's hardcoded vring descriptor location.
Use the linux,usable-memory property to carve out 1MB of memory in case the M4 core is running. Also make sure that the i.MX 7 specific rpmsg driver does not get loaded in case we do not carve out memory.
Signed-off-by: Stefan Agner stefan.agner@toradex.com Signed-off-by: Igor Opaniuk igor.opaniuk@toradex.com
Signed-off-by: Igor Opaniuk igor.opaniuk@gmail.com ---
arch/arm/include/asm/mach-imx/sys_proto.h | 2 ++ board/toradex/colibri_imx7/colibri_imx7.c | 37 +++++++++++++++++++++++ 2 files changed, 39 insertions(+)
diff --git a/arch/arm/include/asm/mach-imx/sys_proto.h b/arch/arm/include/asm/mach-imx/sys_proto.h index 4925dd7894..775cd3df40 100644 --- a/arch/arm/include/asm/mach-imx/sys_proto.h +++ b/arch/arm/include/asm/mach-imx/sys_proto.h @@ -113,6 +113,8 @@ void init_src(void); void init_snvs(void); void imx_wdog_disable_powerdown(void);
+int arch_auxiliary_core_check_up(u32 core_id); + int board_mmc_get_env_dev(int devno);
int nxp_board_rev(void); diff --git a/board/toradex/colibri_imx7/colibri_imx7.c b/board/toradex/colibri_imx7/colibri_imx7.c index 0eb83474c4..6059088bda 100644 --- a/board/toradex/colibri_imx7/colibri_imx7.c +++ b/board/toradex/colibri_imx7/colibri_imx7.c @@ -333,6 +333,43 @@ int checkboard(void) #if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP) int ft_board_setup(void *blob, bd_t *bd) { +#if defined(CONFIG_IMX_BOOTAUX) + int up; + + up = arch_auxiliary_core_check_up(0); + if (up) { + int ret; + int areas = 1; + u64 start[2], size[2]; + + /* + * Reserve 1MB of memory for M4 (1MiB is also the minimum + * alignment for Linux due to MMU section size restrictions). + */ + start[0] = gd->bd->bi_dram[0].start; + size[0] = SZ_256M - SZ_1M; + + /* If needed, create a second entry for memory beyond 256M */ + if (gd->bd->bi_dram[0].size > SZ_256M) { + start[1] = gd->bd->bi_dram[0].start + SZ_256M; + size[1] = gd->bd->bi_dram[0].size - SZ_256M; + areas = 2; + } + + ret = fdt_set_usable_memory(blob, start, size, areas); + if (ret) { + eprintf("Cannot set usable memory\n"); + return ret; + } + } else { + int off; + + off = fdt_node_offset_by_compatible(blob, -1, + "fsl,imx7d-rpmsg"); + if (off > 0) + fdt_status_disabled(blob, off); + } +#endif #if defined(CONFIG_FDT_FIXUP_PARTITIONS) static const struct node_info nodes[] = { { "fsl,imx7d-gpmi-nand", MTD_DEV_TYPE_NAND, }, /* NAND flash */