From: Emanuele Ghidoli emanuele.ghidoli@toradex.com
AM62x SoC is available in multiple variant with a different amount of CPU cores (Cortex-A) available, AM62x1, AM62x2, AM62x4 have respectively 1, 2 or 4 cores.
Update the FDT with the actual core count as read from the SoC registers, with that change is possible to have a single dts/dtb file handling the different variant at runtime.
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 --- arch/arm/mach-k3/common.c | 48 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+)
diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c index f86ccaedc94f..5ee1851e3aaa 100644 --- a/arch/arm/mach-k3/common.c +++ b/arch/arm/mach-k3/common.c @@ -431,10 +431,58 @@ int fdt_fixup_msmc_ram(void *blob, char *parent_path, char *node_name) }
#if defined(CONFIG_OF_SYSTEM_SETUP) +static int fdt_del_node_path(void *blob, const char *path) +{ + int rc; + int nodeoff; + + nodeoff = fdt_path_offset(blob, path); + if (nodeoff < 0) + return 0; /* Not found, skip it */ + + rc = fdt_del_node(blob, nodeoff); + if (rc < 0) + printf("Unable to delete node %s, err=%s\n", path, fdt_strerror(rc)); + else + debug("Deleted node %s\n", path); + return rc; +} + +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 int k3_get_core_nr(void) +{ +#if defined(CONFIG_SOC_K3_AM625) + u32 full_devid = readl(CTRLMMR_WKUP_JTAG_DEVICE_ID); + + return (full_devid & JTAG_DEV_CORE_NR_MASK) >> JTAG_DEV_CORE_NR_SHIFT; +#else + return -1; +#endif +} + int ft_system_setup(void *blob, struct bd_info *bd) { int ret = 0;
+ if (IS_ENABLED(CONFIG_SOC_K3_AM625)) + fdt_fixup_cores_nodes_am625(blob, k3_get_core_nr()); + if (IS_ENABLED(CONFIG_SOC_K3_J721S2) || IS_ENABLED(CONFIG_SOC_K3_AM654) || IS_ENABLED(CONFIG_SOC_K3_J721E)) {