/*
* 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)
#define SDIO_BASE (ARC_PERIPHERAL_BASE + 0xA000)
#define SDIO_UHS_REG_EXT (SDIO_BASE + 0x108)
#define SDIO_UHS_REG_EXT_DIV_2 (2 << 30)
#define HSDK_GPIO_INTC (ARC_PERIPHERAL_BASE + 0x3000)
static void __init hsdk_enable_gpio_intc_wire(void)
{
/*
* Peripherals on CPU Card are wired to cpu intc via intermediate
* DW APB GPIO blocks (mainly for debouncing)
*
* ---------------------
* | snps,archs-intc |
* ---------------------
* |
* ----------------------
* | snps,archs-idu-intc |
* ----------------------
* | | | | |
* | [eth] [USB] [... other peripherals]
* |
* -------------------
* | snps,dw-apb-intc |
* -------------------
* | | | |
* [Bt] [HAPS] [... other peripherals]
*
* Current implementation of "irq-dw-apb-ictl" driver doesn't work well
* with stacked INTCs. In particular problem happens if its master INTC
* not yet instantiated. See discussion here -
* https://lkml.org/lkml/2015/3/4/755
*
* So setup the first gpio block as a passive pass thru and hide it from
* DT hardware topology - connect intc directly to cpu intc
* The GPIO "wire" needs to be init nevertheless (here)
*
* One side adv is that peripheral interrupt handling avoids one nested
* intc ISR hop
*
* According to HSDK User's Manual [1], "Table 2 Interrupt Mapping"
* we have the following GPIO input lines used as sources of interrupt:
* - GPIO[0] - Bluetooth interrupt of RS9113 module
* - GPIO[2] - HAPS interrupt (on HapsTrak 3 connector)
* - GPIO[3] - Audio codec (MAX9880A) interrupt
* - GPIO[8-23] - Available on Arduino and PMOD_x headers
* For now there's no use of Arduino and PMOD_x headers in Linux
* use-case so we only enable lines 0, 2 and 3.
*
* [1] https://github.com/foss-for-synopsys-dwc-arc-processors/ARC-Development-Systems-Forum/wiki/docs/ARC_HSDK_User_Guide.pdf
*/
#define GPIO_INTEN (HSDK_GPIO_INTC + 0x30)
#define GPIO_INTMASK (HSDK_GPIO_INTC + 0x34)
#define GPIO_INTTYPE_LEVEL (HSDK_GPIO_INTC + 0x38)
#define GPIO_INT_POLARITY (HSDK_GPIO_INTC + 0x3c)
#define GPIO_INT_CONNECTED_MASK 0x0d
iowrite32(0xffffffff, (void __iomem *) GPIO_INTMASK);
iowrite32(~GPIO_INT_CONNECTED_MASK, (void __iomem *) GPIO_INTMASK);
iowrite32(0x00000000, (void __iomem *) GPIO_INTTYPE_LEVEL);
iowrite32(0xffffffff, (void __iomem *) GPIO_INT_POLARITY);
iowrite32(GPIO_INT_CONNECTED_MASK, (void __iomem *) GPIO_INTEN);
}
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);
/*
* Switch SDIO external ciu clock divider from default div-by-8 to
* minimum possible div-by-2.
*/
iowrite32(SDIO_UHS_REG_EXT_DIV_2, (void __iomem *) SDIO_UHS_REG_EXT);
hsdk_enable_gpio_intc_wire();
}
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
