u-boot/arch/arm/mach-mvebu/arm64-common.c
Baruch Siach 2b4d964718 arm64: mvebu: a8k: autodetect RAM size
Some Armada 8K boards like Macchiatobin and Clearfog GT-8K use RAM from
external DIMM. Hard coding the RAM size in the device-tree is not
convenient. Fortunately, the ATF that initializes the RAM knows the size
of RAM, and U-Boot can query the ATF using a SMC call.

The ATF maps the lower 3G of RAM starting at address 0. Higher RAM is
mapped at 4G. This leaves a 1G hole between 3G and 4G for IO
peripherals. Use a second bi_dram[] entry to describe the higher RAM
area. As a result, CONFIG_NR_DRAM_BANKS must be set to 2 to use more
than 3GB RAM.

This code in this commit is mostly taken from downstream Marvell U-Boot
code by Grzegorz Jaszczyk.

Cc: Grzegorz Jaszczyk <jaz@semihalf.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Stefan Roese <sr@denx.de>
2018-11-20 13:08:15 +01:00

146 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Stefan Roese <sr@denx.de>
*/
#include <common.h>
#include <dm.h>
#include <fdtdec.h>
#include <linux/libfdt.h>
#include <linux/sizes.h>
#include <pci.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/arch/cpu.h>
#include <asm/arch/soc.h>
#include <asm/armv8/mmu.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* Not all memory is mapped in the MMU. So we need to restrict the
* memory size so that U-Boot does not try to access it. Also, the
* internal registers are located at 0xf000.0000 - 0xffff.ffff.
* Currently only 2GiB are mapped for system memory. This is what
* we pass to the U-Boot subsystem here.
*/
#define USABLE_RAM_SIZE 0x80000000
ulong board_get_usable_ram_top(ulong total_size)
{
if (gd->ram_size > USABLE_RAM_SIZE)
return USABLE_RAM_SIZE;
return gd->ram_size;
}
/*
* On ARMv8, MBus is not configured in U-Boot. To enable compilation
* of the already implemented drivers, lets add a dummy version of
* this function so that linking does not fail.
*/
const struct mbus_dram_target_info *mvebu_mbus_dram_info(void)
{
return NULL;
}
/* DRAM init code ... */
#define MV_SIP_DRAM_SIZE 0x82000010
static u64 a8k_dram_scan_ap_sz(void)
{
struct pt_regs pregs;
pregs.regs[0] = MV_SIP_DRAM_SIZE;
pregs.regs[1] = SOC_REGS_PHY_BASE;
smc_call(&pregs);
return pregs.regs[0];
}
static void a8k_dram_init_banksize(void)
{
/*
* The firmware (ATF) leaves a 1G whole above the 3G mark for IO
* devices. Higher RAM is mapped at 4G.
*
* Config 2 DRAM banks:
* Bank 0 - max size 4G - 1G
* Bank 1 - ram size - 4G + 1G
*/
phys_size_t max_bank0_size = SZ_4G - SZ_1G;
gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE;
if (gd->ram_size <= max_bank0_size) {
gd->bd->bi_dram[0].size = gd->ram_size;
return;
}
gd->bd->bi_dram[0].size = max_bank0_size;
if (CONFIG_NR_DRAM_BANKS > 1) {
gd->bd->bi_dram[1].start = SZ_4G;
gd->bd->bi_dram[1].size = gd->ram_size - max_bank0_size;
}
}
int dram_init_banksize(void)
{
if (CONFIG_IS_ENABLED(ARMADA_8K))
a8k_dram_init_banksize();
else
fdtdec_setup_memory_banksize();
return 0;
}
int dram_init(void)
{
if (CONFIG_IS_ENABLED(ARMADA_8K)) {
gd->ram_size = a8k_dram_scan_ap_sz();
if (gd->ram_size != 0)
return 0;
}
if (fdtdec_setup_mem_size_base() != 0)
return -EINVAL;
return 0;
}
int arch_cpu_init(void)
{
/* Nothing to do (yet) */
return 0;
}
int arch_early_init_r(void)
{
struct udevice *dev;
int ret;
int i;
/*
* Loop over all MISC uclass drivers to call the comphy code
* and init all CP110 devices enabled in the DT
*/
i = 0;
while (1) {
/* Call the comphy code via the MISC uclass driver */
ret = uclass_get_device(UCLASS_MISC, i++, &dev);
/* We're done, once no further CP110 device is found */
if (ret)
break;
}
/* Cause the SATA device to do its early init */
uclass_first_device(UCLASS_AHCI, &dev);
#ifdef CONFIG_DM_PCI
/* Trigger PCIe devices detection */
pci_init();
#endif
return 0;
}