From: Stephen Warren swarren@nvidia.com
In the presence of potentially fragemented memory, we cannot hard-code addresses into environment variables such as kernel_addr_r. Instead, we must calculate those addresses at run-time based on available memory locations. Implement the code to perform such runtime calculation, based on requirements described in environment variables, to allow the user full control over the allocation.
Signed-off-by: Stephen Warren swarren@nvidia.com --- arch/arm/mach-tegra/tegra186/nvtboot_board.c | 265 ++++++++++++++++++++++++++- 1 file changed, 264 insertions(+), 1 deletion(-)
diff --git a/arch/arm/mach-tegra/tegra186/nvtboot_board.c b/arch/arm/mach-tegra/tegra186/nvtboot_board.c index b94eb424aaa2..8ecb45444349 100644 --- a/arch/arm/mach-tegra/tegra186/nvtboot_board.c +++ b/arch/arm/mach-tegra/tegra186/nvtboot_board.c @@ -1,16 +1,278 @@ /* - * Copyright (c) 2016, NVIDIA CORPORATION. + * Copyright (c) 2016-2018, NVIDIA CORPORATION. * * SPDX-License-Identifier: GPL-2.0+ */
+#include <stdlib.h> #include <common.h> #include <fdt_support.h> #include <fdtdec.h> #include <asm/arch/tegra.h> +#include <asm/armv8/mmu.h> + +DECLARE_GLOBAL_DATA_PTR;
extern unsigned long nvtboot_boot_x0;
+/* + * The following few functions run late during the boot process and dynamically + * calculate the load address of various binaries. To keep track of multiple + * allocations, some writable list of RAM banks must be used. tegra_mem_map[] + * is used for this purpose to avoid making yet another copy of the list of RAM + * banks. This is safe because tegra_mem_map[] is only used once during very + * early boot to create U-Boot's page tables, long before this code runs. If + * this assumption becomes invalid later, we can just fix the code to copy the + * list of RAM banks into some private data structure before running. + */ + +extern struct mm_region tegra_mem_map[]; + +static char *gen_varname(const char *var, const char *ext) +{ + size_t len_var = strlen(var); + size_t len_ext = strlen(ext); + size_t len = len_var + len_ext + 1; + char *varext = malloc(len); + + if (!varext) + return 0; + strcpy(varext, var); + strcpy(varext + len_var, ext); + return varext; +} + +static void mark_ram_allocated(int bank, u64 allocated_start, u64 allocated_end) +{ + u64 bank_start = tegra_mem_map[bank].virt; + u64 bank_size = tegra_mem_map[bank].size; + u64 bank_end = bank_start + bank_size; + bool keep_front = allocated_start != bank_start; + bool keep_tail = allocated_end != bank_end; + + if (keep_front && keep_tail) { + /* + * There are CONFIG_NR_DRAM_BANKS DRAM entries in the array, + * starting at index 1 (index 0 is MMIO). So, we are at DRAM + * entry "bank" not "bank - 1" as for a typical 0-base array. + * The number of remaining DRAM entries is therefore + * "CONFIG_NR_DRAM_BANKS - bank". We want to duplicate the + * current entry and shift up the remaining entries, dropping + * the last one. Thus, we must copy one fewer entry than the + * number remaining. + */ + memmove(&tegra_mem_map[bank + 1], &tegra_mem_map[bank], + CONFIG_NR_DRAM_BANKS - bank - 1); + tegra_mem_map[bank].size = allocated_start - bank_start; + bank++; + tegra_mem_map[bank].virt = allocated_end; + tegra_mem_map[bank].phys = allocated_end; + tegra_mem_map[bank].size = bank_end - allocated_end; + } else if (keep_front) { + tegra_mem_map[bank].size = allocated_start - bank_start; + } else if (keep_tail) { + tegra_mem_map[bank].virt = allocated_end; + tegra_mem_map[bank].phys = allocated_end; + tegra_mem_map[bank].size = bank_end - allocated_end; + } else { + /* + * We could move all subsequent banks down in the array but + * that's not necessary for subsequent allocations to work, so + * we skip doing so. + */ + tegra_mem_map[bank].size = 0; + } +} + +static void reserve_ram(u64 start, u64 size) +{ + int bank; + u64 end = start + size; + + for (bank = 1; bank <= CONFIG_NR_DRAM_BANKS; bank++) { + u64 bank_start = tegra_mem_map[bank].virt; + u64 bank_size = tegra_mem_map[bank].size; + u64 bank_end = bank_start + bank_size; + + if (end <= bank_start || start > bank_end) + continue; + mark_ram_allocated(bank, start, end); + break; + } +} + +static u64 alloc_ram(u64 size, u64 align, u64 offset) +{ + int bank; + + for (bank = 1; bank <= CONFIG_NR_DRAM_BANKS; bank++) { + u64 bank_start = tegra_mem_map[bank].virt; + u64 bank_size = tegra_mem_map[bank].size; + u64 bank_end = bank_start + bank_size; + u64 allocated = ROUND(bank_start, align) + offset; + u64 allocated_end = allocated + size; + + if (allocated_end > bank_end) + continue; + mark_ram_allocated(bank, allocated, allocated_end); + return allocated; + } + return 0; +} + +static void set_calculated_aliases(char *aliases, u64 address) +{ + char *tmp, *alias; + int err; + + aliases = strdup(aliases); + if (!aliases) { + pr_err("strdup(aliases) failed"); + return; + } + + tmp = aliases; + while (true) { + alias = strsep(&tmp, " "); + if (!alias) + break; + debug("%s: alias: %s\n", __func__, alias); + err = env_set_hex(alias, address); + if (err) + pr_err("Could not set %s\n", alias); + } + + free(aliases); +} + +static void set_calculated_env_var(const char *var) +{ + char *var_size; + char *var_align; + char *var_offset; + char *var_aliases; + u64 size; + u64 align; + u64 offset; + char *aliases; + u64 address; + int err; + + var_size = gen_varname(var, "_size"); + if (!var_size) + return; + var_align = gen_varname(var, "_align"); + if (!var_align) + goto out_free_var_size; + var_offset = gen_varname(var, "_offset"); + if (!var_offset) + goto out_free_var_align; + var_aliases = gen_varname(var, "_aliases"); + if (!var_aliases) + goto out_free_var_offset; + + size = env_get_hex(var_size, 0); + if (!size) { + pr_err("%s not set or zero\n", var_size); + goto out_free_var_aliases; + } + align = env_get_hex(var_align, 1); + /* Handle extant variables, but with a value of 0 */ + if (!align) + align = 1; + offset = env_get_hex(var_offset, 0); + aliases = env_get(var_aliases); + + debug("%s: Calc var %s; size=%llx, align=%llx, offset=%llx\n", + __func__, var, size, align, offset); + if (aliases) + debug("%s: Aliases: %s\n", __func__, aliases); + + address = alloc_ram(size, align, offset); + if (!address) { + pr_err("Could not allocate %s\n", var); + goto out_free_var_aliases; + } + debug("%s: Address %llx\n", __func__, address); + + err = env_set_hex(var, address); + if (err) + pr_err("Could not set %s\n", var); + if (aliases) + set_calculated_aliases(aliases, address); + +out_free_var_aliases: + free(var_aliases); +out_free_var_offset: + free(var_offset); +out_free_var_align: + free(var_align); +out_free_var_size: + free(var_size); +} + +#ifdef DEBUG +static void dump_ram_banks(void) +{ + int bank; + + for (bank = 1; bank <= CONFIG_NR_DRAM_BANKS; bank++) { + u64 bank_start = tegra_mem_map[bank].virt; + u64 bank_size = tegra_mem_map[bank].size; + u64 bank_end = bank_start + bank_size; + + if (!bank_size) + continue; + printf("%d: %010llx..%010llx (+%010llx)\n", bank - 1, + bank_start, bank_end, bank_size); + } +} +#endif + +static void set_calculated_env_vars(void) +{ + char *vars, *tmp, *var; + +#ifdef DEBUG + printf("RAM banks before any calculated env. var.s:\n"); + dump_ram_banks(); +#endif + + reserve_ram(nvtboot_boot_x0, fdt_totalsize(nvtboot_boot_x0)); + +#ifdef DEBUG + printf("RAM after reserving cboot DTB:\n"); + dump_ram_banks(); +#endif + + vars = env_get("calculated_vars"); + if (!vars) { + debug("%s: No env var calculated_vars\n", __func__); + return; + } + + vars = strdup(vars); + if (!vars) { + pr_err("strdup(calculated_vars) failed"); + return; + } + + tmp = vars; + while (true) { + var = strsep(&tmp, " "); + if (!var) + break; + debug("%s: var: %s\n", __func__, var); + set_calculated_env_var(var); +#ifdef DEBUG + printf("RAM banks affter allocating %s:\n", var); + dump_ram_banks(); +#endif + } + + free(vars); +} + static int set_fdt_addr(void) { int ret; @@ -60,6 +322,7 @@ static int set_ethaddr_from_nvtboot(void)
int tegra_soc_board_init_late(void) { + set_calculated_env_vars(); /* * Ignore errors here; the value may not be used depending on * extlinux.conf or boot script content.