1/*
 2 * ARC HSDK Platform support code
 3 *
 4 * Copyright (C) 2017 Synopsys, Inc. (www.synopsys.com)
 5 *
 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.
 9 */
10
11#include <linux/init.h>
12#include <linux/smp.h>
13#include <asm/arcregs.h>
14#include <asm/io.h>
15#include <asm/mach_desc.h>
16
17#define ARC_CCM_UNUSED_ADDR	0x60000000
18
19static void __init hsdk_init_per_cpu(unsigned int cpu)
20{
21	/*
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.
24	 */
25	if (cpuinfo_arc700[cpu].iccm.sz)
26		write_aux_reg(ARC_REG_AUX_ICCM, ARC_CCM_UNUSED_ADDR);
27
28	/*
29	 * By default DCCM is mapped to 0x8z while this area is used by kernel,
30	 * so move it to currently unused area.
31	 */
32	if (cpuinfo_arc700[cpu].dccm.sz)
33		write_aux_reg(ARC_REG_AUX_DCCM, ARC_CCM_UNUSED_ADDR);
34}
35
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)
40
41#define SDIO_BASE		(ARC_PERIPHERAL_BASE + 0xA000)
42#define SDIO_UHS_REG_EXT	(SDIO_BASE + 0x108)
43#define SDIO_UHS_REG_EXT_DIV_2	(2 << 30)
44
45static void __init hsdk_init_early(void)
46{
47	/*
48	 * PAE remapping for DMA clients does not work due to an RTL bug, so
49	 * CREG_PAE register must be programmed to all zeroes, otherwise it
50	 * will cause problems with DMA to/from peripherals even if PAE40 is
51	 * not used.
52	 */
53
54	/* Default is 1, which means "PAE offset = 4GByte" */
55	writel_relaxed(0, (void __iomem *) CREG_PAE);
56
57	/* Really apply settings made above */
58	writel(1, (void __iomem *) CREG_PAE_UPDATE);
59
60	/*
61	 * Switch SDIO external ciu clock divider from default div-by-8 to
62	 * minimum possible div-by-2.
63	 */
64	iowrite32(SDIO_UHS_REG_EXT_DIV_2, (void __iomem *) SDIO_UHS_REG_EXT);
65}
66
67static const char *hsdk_compat[] __initconst = {
68	"snps,hsdk",
69	NULL,
70};
71
72MACHINE_START(SIMULATION, "hsdk")
73	.dt_compat	= hsdk_compat,
74	.init_early     = hsdk_init_early,
75	.init_per_cpu	= hsdk_init_per_cpu,
76MACHINE_END