u-boot/arch/arm/mach-tegra/tegra186/nvtboot_mem.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

173 lines
5.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2016-2018, NVIDIA CORPORATION.
*/
#include <common.h>
#include <fdt_support.h>
#include <fdtdec.h>
#include <asm/arch/tegra.h>
#include <asm/armv8/mmu.h>
#define SZ_4G 0x100000000ULL
/*
* Size of a region that's large enough to hold the relocated U-Boot and all
* other allocations made around it (stack, heap, page tables, etc.)
* In practice, running "bdinfo" at the shell prompt, the stack reaches about
* 5MB from the address selected for ram_top as of the time of writing,
* so a 16MB region should be plenty.
*/
#define MIN_USABLE_RAM_SIZE SZ_16M
/*
* The amount of space we expect to require for stack usage. Used to validate
* that all reservations fit into the region selected for the relocation target
*/
#define MIN_USABLE_STACK_SIZE SZ_1M
DECLARE_GLOBAL_DATA_PTR;
extern unsigned long nvtboot_boot_x0;
extern struct mm_region tegra_mem_map[];
/*
* These variables are written to before relocation, and hence cannot be
* in.bss, since .bss overlaps the DTB that's appended to the U-Boot binary.
* The section attribute forces this into .data and avoids this issue. This
* also has the nice side-effect of the content being valid after relocation.
*/
/* The number of valid entries in ram_banks[] */
static int ram_bank_count __attribute__((section(".data")));
/*
* The usable top-of-RAM for U-Boot. This is both:
* a) Below 4GB to avoid issues with peripherals that use 32-bit addressing.
* b) At the end of a region that has enough space to hold the relocated U-Boot
* and all other allocations made around it (stack, heap, page tables, etc.)
*/
static u64 ram_top __attribute__((section(".data")));
/* The base address of the region of RAM that ends at ram_top */
static u64 region_base __attribute__((section(".data")));
int dram_init(void)
{
unsigned int na, ns;
const void *nvtboot_blob = (void *)nvtboot_boot_x0;
int node, len, i;
const u32 *prop;
na = fdtdec_get_uint(nvtboot_blob, 0, "#address-cells", 2);
ns = fdtdec_get_uint(nvtboot_blob, 0, "#size-cells", 2);
node = fdt_path_offset(nvtboot_blob, "/memory");
if (node < 0) {
pr_err("Can't find /memory node in nvtboot DTB");
hang();
}
prop = fdt_getprop(nvtboot_blob, node, "reg", &len);
if (!prop) {
pr_err("Can't find /memory/reg property in nvtboot DTB");
hang();
}
/* Calculate the true # of base/size pairs to read */
len /= 4; /* Convert bytes to number of cells */
len /= (na + ns); /* Convert cells to number of banks */
if (len > CONFIG_NR_DRAM_BANKS)
len = CONFIG_NR_DRAM_BANKS;
/* Parse the /memory node, and save useful entries */
gd->ram_size = 0;
ram_bank_count = 0;
for (i = 0; i < len; i++) {
u64 bank_start, bank_end, bank_size, usable_bank_size;
/* Extract raw memory region data from DTB */
bank_start = fdt_read_number(prop, na);
prop += na;
bank_size = fdt_read_number(prop, ns);
prop += ns;
gd->ram_size += bank_size;
bank_end = bank_start + bank_size;
debug("Bank %d: %llx..%llx (+%llx)\n", i,
bank_start, bank_end, bank_size);
/*
* Align the bank to MMU section size. This is not strictly
* necessary, since the translation table construction code
* handles page granularity without issue. However, aligning
* the MMU entries reduces the size and number of levels in the
* page table, so is worth it.
*/
bank_start = ROUND(bank_start, SZ_2M);
bank_end = bank_end & ~(SZ_2M - 1);
bank_size = bank_end - bank_start;
debug(" aligned: %llx..%llx (+%llx)\n",
bank_start, bank_end, bank_size);
if (bank_end <= bank_start)
continue;
/* Record data used to create MMU translation tables */
ram_bank_count++;
/* Index below is deliberately 1-based to skip MMIO entry */
tegra_mem_map[ram_bank_count].virt = bank_start;
tegra_mem_map[ram_bank_count].phys = bank_start;
tegra_mem_map[ram_bank_count].size = bank_size;
tegra_mem_map[ram_bank_count].attrs =
PTE_BLOCK_MEMTYPE(MT_NORMAL) | PTE_BLOCK_INNER_SHARE;
/* Determine best bank to relocate U-Boot into */
if (bank_end > SZ_4G)
bank_end = SZ_4G;
debug(" end %llx (usable)\n", bank_end);
usable_bank_size = bank_end - bank_start;
debug(" size %llx (usable)\n", usable_bank_size);
if ((usable_bank_size >= MIN_USABLE_RAM_SIZE) &&
(bank_end > ram_top)) {
ram_top = bank_end;
region_base = bank_start;
debug("ram top now %llx\n", ram_top);
}
}
/* Ensure memory map contains the desired sentinel entry */
tegra_mem_map[ram_bank_count + 1].virt = 0;
tegra_mem_map[ram_bank_count + 1].phys = 0;
tegra_mem_map[ram_bank_count + 1].size = 0;
tegra_mem_map[ram_bank_count + 1].attrs = 0;
/* Error out if a relocation target couldn't be found */
if (!ram_top) {
pr_err("Can't find a usable RAM top");
hang();
}
return 0;
}
int dram_init_banksize(void)
{
int i;
if ((gd->start_addr_sp - region_base) < MIN_USABLE_STACK_SIZE) {
pr_err("Reservations exceed chosen region size");
hang();
}
for (i = 0; i < ram_bank_count; i++) {
gd->bd->bi_dram[i].start = tegra_mem_map[1 + i].virt;
gd->bd->bi_dram[i].size = tegra_mem_map[1 + i].size;
}
#ifdef CONFIG_PCI
gd->pci_ram_top = ram_top;
#endif
return 0;
}
ulong board_get_usable_ram_top(ulong total_size)
{
return ram_top;
}