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ARC: [plat-hsdk] initial port for HSDK board

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This initial port adds support of ARC HS Development Kit board with some
basic features such serial port, USB, SD/MMC and Ethernet.

Essentially we run Linux kernel on all 4 cores (i.e. utilize SMP) and
heavily use IO Coherency for speeding-up DMA-aware peripherals.

Note as opposed to other ARC boards we link Linux kernel to
0x9000_0000 intentionally because cores 1 and 3 configured with DCCM
situated at our more usual link base 0x8000_0000. We still can use
memory region starting at 0x8000_0000 as we reallocate DCCM in our
platform code.

Note that PAE remapping for DMA clients does not work due to an RTL bug,
so CREG_PAE register must be programmed to all zeroes, otherwise it will
cause problems with DMA to/from peripherals even if PAE40 is not used.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Alexey Brodkin
2017-08-15 21:13:55 +03:00
committed by Vineet Gupta
parent 9ed68785f7
commit a518d63777
9 changed files with 365 additions and 2 deletions
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66
arch/arc/plat-hsdk/platform.c Normal file
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/*
* ARC HSDK Platform support code
*
* Copyright (C) 2017 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/smp.h>
#include <asm/arcregs.h>
#include <asm/io.h>
#include <asm/mach_desc.h>
#define ARC_CCM_UNUSED_ADDR 0x60000000
static void __init hsdk_init_per_cpu(unsigned int cpu)
{
/*
* By default ICCM is mapped to 0x7z while this area is used for
* kernel virtual mappings, so move it to currently unused area.
*/
if (cpuinfo_arc700[cpu].iccm.sz)
write_aux_reg(ARC_REG_AUX_ICCM, ARC_CCM_UNUSED_ADDR);
/*
* By default DCCM is mapped to 0x8z while this area is used by kernel,
* so move it to currently unused area.
*/
if (cpuinfo_arc700[cpu].dccm.sz)
write_aux_reg(ARC_REG_AUX_DCCM, ARC_CCM_UNUSED_ADDR);
}
#define ARC_PERIPHERAL_BASE 0xf0000000
#define CREG_BASE (ARC_PERIPHERAL_BASE + 0x1000)
#define CREG_PAE (CREG_BASE + 0x180)
#define CREG_PAE_UPDATE (CREG_BASE + 0x194)
static void __init hsdk_init_early(void)
{
/*
* PAE remapping for DMA clients does not work due to an RTL bug, so
* CREG_PAE register must be programmed to all zeroes, otherwise it
* will cause problems with DMA to/from peripherals even if PAE40 is
* not used.
*/
/* Default is 1, which means "PAE offset = 4GByte" */
writel_relaxed(0, (void __iomem *) CREG_PAE);
/* Really apply settings made above */
writel(1, (void __iomem *) CREG_PAE_UPDATE);
}
static const char *hsdk_compat[] __initconst = {
"snps,hsdk",
NULL,
};
MACHINE_START(SIMULATION, "hsdk")
.dt_compat = hsdk_compat,
.init_early = hsdk_init_early,
.init_per_cpu = hsdk_init_per_cpu,
MACHINE_END