diff options
Diffstat (limited to 'arch/arc/plat-hsdk/platform.c')
-rw-r--r-- | arch/arc/plat-hsdk/platform.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/arc/plat-hsdk/platform.c b/arch/arc/plat-hsdk/platform.c new file mode 100644 index 000000000000..a2e7fd17e36d --- /dev/null +++ b/arch/arc/plat-hsdk/platform.c @@ -0,0 +1,66 @@ +/* + * 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 |