u-boot/arch/mips/mach-mscc/cpu.c
Gregory CLEMENT 6bd8231a6d MSCC: add support for Luton SoCs
As the Ocelots SoCs, this family of SoCs are found in the Microsemi
Switches solution.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
2018-12-19 15:23:01 +01:00

102 lines
3 KiB
C

// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
/*
* Copyright (c) 2018 Microsemi Corporation
*/
#include <common.h>
#include <asm/io.h>
#include <asm/types.h>
#include <mach/tlb.h>
#include <mach/ddr.h>
DECLARE_GLOBAL_DATA_PTR;
#if CONFIG_SYS_SDRAM_SIZE <= SZ_64M
#define MSCC_RAM_TLB_SIZE SZ_64M
#define MSCC_ATTRIB2 MMU_REGIO_INVAL
#elif CONFIG_SYS_SDRAM_SIZE <= SZ_128M
#define MSCC_RAM_TLB_SIZE SZ_64M
#define MSCC_ATTRIB2 MMU_REGIO_RW
#elif CONFIG_SYS_SDRAM_SIZE <= SZ_256M
#define MSCC_RAM_TLB_SIZE SZ_256M
#define MSCC_ATTRIB2 MMU_REGIO_INVAL
#elif CONFIG_SYS_SDRAM_SIZE <= SZ_512M
#define MSCC_RAM_TLB_SIZE SZ_256M
#define MSCC_ATTRIB2 MMU_REGIO_RW
#else
#define MSCC_RAM_TLB_SIZE SZ_512M
#define MSCC_ATTRIB2 MMU_REGIO_RW
#endif
/* NOTE: lowlevel_init() function does not have access to the
* stack. Thus, all called functions must be inlined, and (any) local
* variables must be kept in registers.
*/
void vcoreiii_tlb_init(void)
{
register int tlbix = 0;
/*
* Unlike most of the MIPS based SoCs, the IO register address
* are not in KSEG0. The mainline linux kernel built in legacy
* mode needs to access some of the registers very early in
* the boot and make the assumption that the bootloader has
* already configured them, so we have to match this
* expectation.
*/
create_tlb(tlbix++, MSCC_IO_ORIGIN1_OFFSET, SZ_16M, MMU_REGIO_RW,
MMU_REGIO_RW);
#ifdef CONFIG_SOC_LUTON
create_tlb(tlbix++, MSCC_IO_ORIGIN2_OFFSET, SZ_16M, MMU_REGIO_RW,
MMU_REGIO_RW);
#endif
#if CONFIG_SYS_TEXT_BASE == MSCC_FLASH_TO
/*
* If U-Boot is located in NOR then we want to be able to use
* the data cache in order to boot in a decent duration
*/
create_tlb(tlbix++, MSCC_FLASH_TO, SZ_16M, MMU_REGIO_RO_C,
MMU_REGIO_RO_C);
create_tlb(tlbix++, MSCC_FLASH_TO + SZ_32M, SZ_16M, MMU_REGIO_RO_C,
MMU_REGIO_RO_C);
/*
* Using cache for RAM also helps to improve boot time. Thanks
* to this the time to relocate U-Boot in RAM went from 2.092
* secs to 0.104 secs.
*/
create_tlb(tlbix++, MSCC_DDR_TO, MSCC_RAM_TLB_SIZE, MMU_REGIO_RW,
MSCC_ATTRIB2);
/* Enable caches by clearing the bit ERL, which is set on reset */
write_c0_status(read_c0_status() & ~BIT(2));
#endif /* CONFIG_SYS_TEXT_BASE */
}
int mach_cpu_init(void)
{
/* Speed up NOR flash access */
#ifdef CONFIG_SOC_LUTON
writel(ICPU_PI_MST_CFG_TRISTATE_CTRL +
ICPU_PI_MST_CFG_CLK_DIV(4), BASE_CFG + ICPU_PI_MST_CFG);
writel(ICPU_SPI_MST_CFG_FAST_READ_ENA +
ICPU_SPI_MST_CFG_CS_DESELECT_TIME(0x19) +
ICPU_SPI_MST_CFG_CLK_DIV(9), BASE_CFG + ICPU_SPI_MST_CFG);
#else
writel(ICPU_SPI_MST_CFG_CS_DESELECT_TIME(0x19) +
ICPU_SPI_MST_CFG_CLK_DIV(9), BASE_CFG + ICPU_SPI_MST_CFG);
/*
* Legacy and mainline linux kernel expect that the
* interruption map was set as it was done by redboot.
*/
writel(~0, BASE_CFG + ICPU_DST_INTR_MAP(0));
writel(0, BASE_CFG + ICPU_DST_INTR_MAP(1));
writel(0, BASE_CFG + ICPU_DST_INTR_MAP(2));
writel(0, BASE_CFG + ICPU_DST_INTR_MAP(3));
#endif
return 0;
}