From: Emanuele Ghidoli emanuele.ghidoli@toradex.com
AM62x SoC is available in multiple variant: - CPU cores (Cortex-A) AM62x1 (1 core), AM62x2 (2 cores), AM62x4 (4 cores) - GPU AM625x with GPU, AM623x without GPU - PRU (Programmable RT unit) can be present or not on AM62x2/AM62x4
Remove the relevant FDT nodes by reading the actual configuration from the SoC registers, with that change is possible to have a single dts/dtb file handling the different variant at runtime. While removing GPU node and CPU nodes also the watchdog node in the same Module Domain is removed.
A similar approach is implemented for example on i.MX8 and STM32MP1 SoC.
Signed-off-by: Emanuele Ghidoli emanuele.ghidoli@toradex.com Signed-off-by: Francesco Dolcini francesco.dolcini@toradex.com --- v2: - add GPU/PRU fixups --- arch/arm/mach-k3/Makefile | 1 + arch/arm/mach-k3/am625_fdt.c | 71 +++++++++++++++++++++++++++++++++++ arch/arm/mach-k3/common_fdt.c | 18 +++++++++ 3 files changed, 90 insertions(+) create mode 100644 arch/arm/mach-k3/am625_fdt.c
diff --git a/arch/arm/mach-k3/Makefile b/arch/arm/mach-k3/Makefile index 499bdaa7153d..fd77b8bbba5c 100644 --- a/arch/arm/mach-k3/Makefile +++ b/arch/arm/mach-k3/Makefile @@ -15,6 +15,7 @@ ifeq ($(CONFIG_OF_LIBFDT)$(CONFIG_OF_SYSTEM_SETUP),yy) obj-$(CONFIG_SOC_K3_AM654) += am654_fdt.o obj-$(CONFIG_SOC_K3_J721E) += j721e_fdt.o obj-$(CONFIG_SOC_K3_J721S2) += j721s2_fdt.o +obj-$(CONFIG_SOC_K3_AM625) += am625_fdt.o endif ifeq ($(CONFIG_SPL_BUILD),y) obj-$(CONFIG_SOC_K3_AM654) += am654_init.o diff --git a/arch/arm/mach-k3/am625_fdt.c b/arch/arm/mach-k3/am625_fdt.c new file mode 100644 index 000000000000..37806907af1a --- /dev/null +++ b/arch/arm/mach-k3/am625_fdt.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2023 Toradex - https://www.toradex.com/ + */ + +#include <asm/hardware.h> +#include "common_fdt.h" +#include <fdt_support.h> + +static void fdt_fixup_cores_nodes_am625(void *blob, int core_nr) +{ + char node_path[32]; + + if (core_nr < 1) + return; + + for (; core_nr < 4; core_nr++) { + snprintf(node_path, sizeof(node_path), "/cpus/cpu@%d", core_nr); + fdt_del_node_path(blob, node_path); + snprintf(node_path, sizeof(node_path), "/cpus/cpu-map/cluster0/core%d", core_nr); + fdt_del_node_path(blob, node_path); + snprintf(node_path, sizeof(node_path), "/bus@f0000/watchdog@e0%d0000", core_nr); + fdt_del_node_path(blob, node_path); + } +} + +static void fdt_fixup_gpu_nodes_am625(void *blob, int has_gpu) +{ + if (!has_gpu) { + fdt_del_node_path(blob, "/bus@f0000/gpu@fd00000"); + fdt_del_node_path(blob, "/bus@f0000/watchdog@e0f0000"); + } +} + +static void fdt_fixup_pru_node_am625(void *blob, int has_pru) +{ + if (!has_pru) + fdt_del_node_path(blob, "/bus@f0000/pruss@30040000"); +} + +static int k3_get_core_nr(void) +{ + u32 full_devid = readl(CTRLMMR_WKUP_JTAG_DEVICE_ID); + + return (full_devid & JTAG_DEV_CORE_NR_MASK) >> JTAG_DEV_CORE_NR_SHIFT; +} + +static int k3_has_pru(void) +{ + u32 full_devid = readl(CTRLMMR_WKUP_JTAG_DEVICE_ID); + u32 feature_mask = (full_devid & JTAG_DEV_FEATURES_MASK) >> + JTAG_DEV_FEATURES_SHIFT; + + return !(feature_mask & JTAG_DEV_FEATURE_NO_PRU); +} + +static int k3_has_gpu(void) +{ + u32 full_devid = readl(CTRLMMR_WKUP_JTAG_DEVICE_ID); + + return (full_devid & JTAG_DEV_GPU_MASK) >> JTAG_DEV_GPU_SHIFT; +} + +int ft_system_setup(void *blob, struct bd_info *bd) +{ + fdt_fixup_cores_nodes_am625(blob, k3_get_core_nr()); + fdt_fixup_gpu_nodes_am625(blob, k3_has_gpu()); + fdt_fixup_pru_node_am625(blob, k3_has_pru()); + + return 0; +} diff --git a/arch/arm/mach-k3/common_fdt.c b/arch/arm/mach-k3/common_fdt.c index c86fe3a5890b..9478f605441f 100644 --- a/arch/arm/mach-k3/common_fdt.c +++ b/arch/arm/mach-k3/common_fdt.c @@ -93,3 +93,21 @@ int fdt_fixup_msmc_ram_k3(void *blob)
return ret; } + +int fdt_del_node_path(void *blob, const char *path) +{ + int ret; + int nodeoff; + + nodeoff = fdt_path_offset(blob, path); + if (nodeoff < 0) + return 0; /* Not found, skip it */ + + ret = fdt_del_node(blob, nodeoff); + if (ret < 0) + printf("Unable to delete node %s, err=%s\n", path, fdt_strerror(ret)); + else + debug("Deleted node %s\n", path); + + return ret; +}