ARC: [axs101] Add support for AXS101 SDP (software development platform)

The AXS10x platforms consist of a mainboard with peripherals,
on which several daughter cards can be placed. The daughter cards
typically contain a CPU and memory.

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

3 files changed, 342 insertions, 0 deletions

diff --git a/arch/arc/plat-axs10x/Kconfig b/arch/arc/plat-axs10x/Kconfig
new file mode 100644
index 0000000..45641ca
--- /dev/null
+++ b/arch/arc/plat-axs10x/Kconfig
@@ -0,0 +1,35 @@
+#
+# Copyright (C) 2013-15 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.
+#
+
+config ARC_PLAT_AXS10X
+	bool "Synopsys ARC AXS10x Software Development Platforms"
+	select DW_APB_ICTL
+	select GPIO_DWAPB
+	select OF_GPIO
+	select GENERIC_IRQ_CHIP
+	select ARCH_REQUIRE_GPIOLIB
+	help
+	  Support for the ARC AXS10x Software Development Platforms.
+
+	  The AXS10x Platforms consist of a mainboard with peripherals,
+	  on which several daughter cards can be placed. The daughter cards
+	  typically contain a CPU and memory.
+
+if ARC_PLAT_AXS10X
+
+config AXS101
+	bool "AXS101 with AXC001 CPU Card (ARC 770D/EM6/AS221)"
+	help
+	  This adds support for the 770D/EM6/AS221 CPU Card. Only the ARC
+	  770D is supported in Linux.
+
+	  The AXS101 Platform consists of an AXS10x mainboard with
+	  this daughtercard. Please use the axs101.dts device tree
+	  with this configuration.
+
+endif
diff --git a/arch/arc/plat-axs10x/Makefile b/arch/arc/plat-axs10x/Makefile
new file mode 100644
index 0000000..d4748f2
--- /dev/null
+++ b/arch/arc/plat-axs10x/Makefile
@@ -0,0 +1,9 @@
+#
+# Copyright (C) 2013-15 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.
+#
+
+obj-$(CONFIG_ARC_PLAT_AXS10X) += axs10x.o
diff --git a/arch/arc/plat-axs10x/axs10x.c b/arch/arc/plat-axs10x/axs10x.c
new file mode 100644
index 0000000..2e7686d
--- /dev/null
+++ b/arch/arc/plat-axs10x/axs10x.c
@@ -0,0 +1,298 @@
+/*
+ * AXS101 Software Development Platform
+ *
+ * Copyright (C) 2013-15 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/of_platform.h>
+#include <asm/mach_desc.h>
+#include <asm/io.h>
+
+#define AXS_MB_CGU		0xE0010000
+#define AXS_MB_CREG		0xE0011000
+
+#define CREG_MB_IRQ_MUX		(AXS_MB_CREG + 0x214)
+#define CREG_MB_SW_RESET	(AXS_MB_CREG + 0x220)
+#define CREG_MB_VER		(AXS_MB_CREG + 0x230)
+#define CREG_MB_CONFIG		(AXS_MB_CREG + 0x234)
+
+#define AXC001_CREG		0xF0001000
+#define AXC001_GPIO_INTC	0xF0003000
+
+#define CREG_CPU_ADDR_770	(AXC001_CREG + 0x20)
+#define CREG_CPU_ADDR_TUNN	(AXC001_CREG + 0x60)
+#define CREG_CPU_ADDR_770_UPD	(AXC001_CREG + 0x34)
+#define CREG_CPU_ADDR_TUNN_UPD	(AXC001_CREG + 0x74)
+
+#define CREG_CPU_ARC770_IRQ_MUX	(AXC001_CREG + 0x114)
+#define CREG_CPU_GPIO_UART_MUX	(AXC001_CREG + 0x120)
+
+static void enable_gpio_intc_wire(void)
+{
+	/*
+	 * Peripherals on CPU Card and Mother Board are wired to cpu intc via
+	 * intermediate DW APB GPIO blocks (mainly for debouncing)
+	 *
+	 *         ---------------------
+	 *        |  snps,arc700-intc |
+	 *        ---------------------
+	 *          | #7          | #15
+	 * -------------------   -------------------
+	 * | snps,dw-apb-gpio |  | snps,dw-apb-gpio |
+	 * -------------------   -------------------
+	 *        |                         |
+	 *        |                 [ Debug UART on cpu card ]
+	 *        |
+	 * ------------------------
+	 * | snps,dw-apb-intc (MB)|
+	 * ------------------------
+	 *  |      |       |      |
+	 * [eth] [uart]        [... other perip on Main Board]
+	 *
+	 * 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 MB 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
+	 */
+#define GPIO_INTEN		(AXC001_GPIO_INTC + 0x30)
+#define GPIO_INTMASK		(AXC001_GPIO_INTC + 0x34)
+#define GPIO_INTTYPE_LEVEL	(AXC001_GPIO_INTC + 0x38)
+#define GPIO_INT_POLARITY	(AXC001_GPIO_INTC + 0x3c)
+#define MB_TO_GPIO_IRQ		12
+
+	iowrite32(~(1 << MB_TO_GPIO_IRQ), (void __iomem *) GPIO_INTMASK);
+	iowrite32(0, (void __iomem *) GPIO_INTTYPE_LEVEL);
+	iowrite32(~0, (void __iomem *) GPIO_INT_POLARITY);
+	iowrite32(1 << MB_TO_GPIO_IRQ, (void __iomem *) GPIO_INTEN);
+}
+
+static void axs10x_print_board_ver(unsigned int creg, const char *str)
+{
+	union ver {
+		struct {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+			unsigned int pad:11, y:12, m:4, d:5;
+#else
+			unsigned int d:5, m:4, y:12, pad:11;
+#endif
+		};
+		unsigned int val;
+	} board;
+
+	board.val = ioread32((void __iomem *)creg);
+	pr_info("AXS: %s FPGA Date: %u-%u-%u\n", str, board.d, board.m,
+		board.y);
+}
+
+static void axs10x_early_init(void)
+{
+	int mb_rev;
+	char mb[32];
+
+	/* Determine motherboard version */
+	if (ioread32((void __iomem *) CREG_MB_CONFIG) & (1 << 28))
+		mb_rev = 3;	/* HT-3 (rev3.0) */
+	else
+		mb_rev = 2;	/* HT-2 (rev2.0) */
+
+	enable_gpio_intc_wire();
+
+	scnprintf(mb, 32, "MainBoard v%d", mb_rev);
+	axs10x_print_board_ver(CREG_MB_VER, mb);
+}
+
+/*
+ * Set up System Memory Map for ARC cpu / peripherals controllers
+ *
+ * Each AXI master has a 4GB memory map specified as 16 apertures of 256MB, each
+ * of which maps to a corresponding 256MB aperture in Target slave memory map.
+ *
+ * e.g. ARC cpu AXI Master's aperture 8 (0x8000_0000) is mapped to aperture 0
+ * (0x0000_0000) of DDR Port 0 (slave #1)
+ *
+ * Access from cpu to MB controllers such as GMAC is setup using AXI Tunnel:
+ * which has master/slaves on both ends.
+ * e.g. aperture 14 (0xE000_0000) of ARC cpu is mapped to aperture 14
+ * (0xE000_0000) of CPU Card AXI Tunnel slave (slave #3) which is mapped to
+ * MB AXI Tunnel Master, which also has a mem map setup
+ *
+ * In the reverse direction, MB AXI Masters (e.g. GMAC) mem map is setup
+ * to map to MB AXI Tunnel slave which connects to CPU Card AXI Tunnel Master
+ */
+struct aperture {
+	unsigned int slave_sel:4, slave_off:4, pad:24;
+};
+
+/* CPU Card target slaves */
+#define AXC001_SLV_NONE			0
+#define AXC001_SLV_DDR_PORT0		1
+#define AXC001_SLV_SRAM			2
+#define AXC001_SLV_AXI_TUNNEL		3
+#define AXC001_SLV_AXI2APB		6
+#define AXC001_SLV_DDR_PORT1		7
+
+/* MB AXI Target slaves */
+#define AXS_MB_SLV_NONE			0
+#define AXS_MB_SLV_AXI_TUNNEL_CPU	1
+#define AXS_MB_SLV_AXI_TUNNEL_HAPS	2
+#define AXS_MB_SLV_SRAM			3
+#define AXS_MB_SLV_CONTROL		4
+
+/* MB AXI masters */
+#define AXS_MB_MST_TUNNEL_CPU		0
+#define AXS_MB_MST_USB_OHCI		10
+
+/*
+ * memmap for ARC core on CPU Card
+ */
+static const struct aperture axc001_memmap[16] = {
+	{AXC001_SLV_AXI_TUNNEL,		0x0},
+	{AXC001_SLV_AXI_TUNNEL,		0x1},
+	{AXC001_SLV_SRAM,		0x0}, /* 0x2000_0000: Local SRAM */
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_DDR_PORT0,		0x0}, /* 0x8000_0000: DDR   0..256M */
+	{AXC001_SLV_DDR_PORT0,		0x1}, /* 0x9000_0000: DDR 256..512M */
+	{AXC001_SLV_DDR_PORT1,		0x0},
+	{AXC001_SLV_DDR_PORT1,		0x1},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_AXI_TUNNEL,		0xD},
+	{AXC001_SLV_AXI_TUNNEL,		0xE}, /* MB: CREG, CGU... */
+	{AXC001_SLV_AXI2APB,		0x0}, /* CPU Card local CREG, CGU... */
+};
+
+/*
+ * memmap for CPU Card AXI Tunnel Master (for access by MB controllers)
+ * GMAC (MB) -> MB AXI Tunnel slave -> CPU Card AXI Tunnel Master -> DDR
+ */
+static const struct aperture axc001_axi_tunnel_memmap[16] = {
+	{AXC001_SLV_AXI_TUNNEL,		0x0},
+	{AXC001_SLV_AXI_TUNNEL,		0x1},
+	{AXC001_SLV_SRAM,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_DDR_PORT0,		0x0},
+	{AXC001_SLV_DDR_PORT0,		0x1},
+	{AXC001_SLV_DDR_PORT1,		0x0},
+	{AXC001_SLV_DDR_PORT1,		0x1},
+	{AXC001_SLV_NONE,		0x0},
+	{AXC001_SLV_AXI_TUNNEL,		0xD},
+	{AXC001_SLV_AXI_TUNNEL,		0xE},
+	{AXC001_SLV_AXI2APB,		0x0},
+};
+
+/*
+ * memmap for MB AXI Masters
+ * Same mem map for all perip controllers as well as MB AXI Tunnel Master
+ */
+static const struct aperture axs_mb_memmap[16] = {
+	{AXS_MB_SLV_SRAM,		0x0},
+	{AXS_MB_SLV_SRAM,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_AXI_TUNNEL_CPU,	0x8},	/* DDR on CPU Card */
+	{AXS_MB_SLV_AXI_TUNNEL_CPU,	0x9},	/* DDR on CPU Card */
+	{AXS_MB_SLV_AXI_TUNNEL_CPU,	0xA},
+	{AXS_MB_SLV_AXI_TUNNEL_CPU,	0xB},
+	{AXS_MB_SLV_NONE,		0x0},
+	{AXS_MB_SLV_AXI_TUNNEL_HAPS,	0xD},
+	{AXS_MB_SLV_CONTROL,		0x0},	/* MB Local CREG, CGU... */
+	{AXS_MB_SLV_AXI_TUNNEL_CPU,	0xF},
+};
+
+static noinline void
+axs101_set_memmap(void __iomem *base, const struct aperture map[16])
+{
+	unsigned int slave_select, slave_offset;
+	int i;
+
+	slave_select = slave_offset = 0;
+	for (i = 0; i < 8; i++) {
+		slave_select |= map[i].slave_sel << (i << 2);
+		slave_offset |= map[i].slave_off << (i << 2);
+	}
+
+	iowrite32(slave_select, base + 0x0);	/* SLV0 */
+	iowrite32(slave_offset, base + 0x8);	/* OFFSET0 */
+
+	slave_select = slave_offset = 0;
+	for (i = 0; i < 8; i++) {
+		slave_select |= map[i+8].slave_sel << (i << 2);
+		slave_offset |= map[i+8].slave_off << (i << 2);
+	}
+
+	iowrite32(slave_select, base + 0x4);	/* SLV1 */
+	iowrite32(slave_offset, base + 0xC);	/* OFFSET1 */
+}
+
+static void axs101_early_init(void)
+{
+	int i;
+
+	/* ARC 770D memory view */
+	axs101_set_memmap((void __iomem *) CREG_CPU_ADDR_770, axc001_memmap);
+	iowrite32(1, (void __iomem *) CREG_CPU_ADDR_770_UPD);
+
+	/* AXI tunnel memory map (incoming traffic from MB into CPU Card */
+	axs101_set_memmap((void __iomem *) CREG_CPU_ADDR_TUNN,
+			      axc001_axi_tunnel_memmap);
+	iowrite32(1, (void __iomem *) CREG_CPU_ADDR_TUNN_UPD);
+
+	/* MB peripherals memory map */
+	for (i = AXS_MB_MST_TUNNEL_CPU; i <= AXS_MB_MST_USB_OHCI; i++)
+		axs101_set_memmap((void __iomem *) AXS_MB_CREG + (i << 4),
+				      axs_mb_memmap);
+
+	iowrite32(0x3ff, (void __iomem *) AXS_MB_CREG + 0x100); /* Update */
+
+	/* GPIO pins 18 and 19 are used as UART rx and tx, respectively. */
+	iowrite32(0x01, (void __iomem *) CREG_CPU_GPIO_UART_MUX);
+
+	/* Set up the MB interrupt system: mux interrupts to GPIO7) */
+	iowrite32(0x01, (void __iomem *) CREG_MB_IRQ_MUX);
+
+	/* reset ethernet and ULPI interfaces */
+	iowrite32(0x18, (void __iomem *) CREG_MB_SW_RESET);
+
+	/* map GPIO 14:10 to ARC 9:5 (IRQ mux change for MB v2 onwards) */
+	iowrite32(0x52, (void __iomem *) CREG_CPU_ARC770_IRQ_MUX);
+
+	axs10x_early_init();
+}
+
+static const char *axs101_compat[] __initconst = {
+	"snps,axs101",
+	NULL,
+};
+
+MACHINE_START(AXS101, "axs101")
+	.dt_compat	= axs101_compat,
+	.init_early	= axs101_early_init,
+MACHINE_END