2 * ARC HSDK Platform support code
4 * Copyright (C) 2017 Synopsys, Inc. (www.synopsys.com)
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/init.h>
12 #include <linux/smp.h>
13 #include <asm/arcregs.h>
15 #include <asm/mach_desc.h>
17 #define ARC_CCM_UNUSED_ADDR 0x60000000
19 static void __init hsdk_init_per_cpu(unsigned int cpu)
22 * By default ICCM is mapped to 0x7z while this area is used for
23 * kernel virtual mappings, so move it to currently unused area.
25 if (cpuinfo_arc700[cpu].iccm.sz)
26 write_aux_reg(ARC_REG_AUX_ICCM, ARC_CCM_UNUSED_ADDR);
29 * By default DCCM is mapped to 0x8z while this area is used by kernel,
30 * so move it to currently unused area.
32 if (cpuinfo_arc700[cpu].dccm.sz)
33 write_aux_reg(ARC_REG_AUX_DCCM, ARC_CCM_UNUSED_ADDR);
36 #define ARC_PERIPHERAL_BASE 0xf0000000
37 #define CREG_BASE (ARC_PERIPHERAL_BASE + 0x1000)
38 #define CREG_PAE (CREG_BASE + 0x180)
39 #define CREG_PAE_UPDATE (CREG_BASE + 0x194)
41 static void __init hsdk_init_early(void)
44 * PAE remapping for DMA clients does not work due to an RTL bug, so
45 * CREG_PAE register must be programmed to all zeroes, otherwise it
46 * will cause problems with DMA to/from peripherals even if PAE40 is
50 /* Default is 1, which means "PAE offset = 4GByte" */
51 writel_relaxed(0, (void __iomem *) CREG_PAE);
53 /* Really apply settings made above */
54 writel(1, (void __iomem *) CREG_PAE_UPDATE);
57 static const char *hsdk_compat[] __initconst = {
62 MACHINE_START(SIMULATION, "hsdk")
63 .dt_compat = hsdk_compat,
64 .init_early = hsdk_init_early,
65 .init_per_cpu = hsdk_init_per_cpu,