powerpc/amigaone: Add platform support for AmigaOne

This commit adds the setup code for booting Linux on AmigaOne G3SE (G3
only), AmigaOne XE and uA1 (G3/G4) desktop computers. These boards were
sold by Eyetech and are based on MAI Logic's Teron boards and its
Articia S northbridge.
The AmigaOne uses U-boot as firmware, which doesn't support a flattened
device tree yet. The northbridge has some design flaws, which makes it
necessary to use non cacheable memory for DMA operations
(CONFIG_NOT_COHERENT_CACHE) and to avoid setting the coherence (M) flag
for memory pages.

Signed-off-by: Gerhard Pircher <gerhard_pircher@gmx.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 189 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/amigaone/Kconfig b/arch/powerpc/platforms/amigaone/Kconfig
new file mode 100644
index 00000000000..9276a96cede
--- /dev/null
+++ b/arch/powerpc/platforms/amigaone/Kconfig
@@ -0,0 +1,18 @@
+config AMIGAONE
+        bool "Eyetech AmigaOne/MAI Teron"
+        depends on PPC32 && BROKEN_ON_SMP && PPC_MULTIPLATFORM
+        select PPC_I8259
+        select PPC_INDIRECT_PCI
+        select PPC_UDBG_16550
+        select PCI
+        select NOT_COHERENT_CACHE
+        select CHECK_CACHE_COHERENCY
+        select DEFAULT_UIMAGE
+        select PCSPKR_PLATFORM
+        help
+        Select AmigaOne for the following machines:
+        - AmigaOne SE/Teron CX (G3 only)
+        - AmigaOne XE/Teron PX
+        - uA1/Teron mini
+          More information is available at:
+          <http://amigaone-linux.sourceforge.net/>.
diff --git a/arch/powerpc/platforms/amigaone/Makefile b/arch/powerpc/platforms/amigaone/Makefile
new file mode 100644
index 00000000000..e6885b3b2ee
--- /dev/null
+++ b/arch/powerpc/platforms/amigaone/Makefile
@@ -0,0 +1 @@
+obj-y   += setup.o
diff --git a/arch/powerpc/platforms/amigaone/setup.c b/arch/powerpc/platforms/amigaone/setup.c
new file mode 100644
index 00000000000..443035366c1
--- /dev/null
+++ b/arch/powerpc/platforms/amigaone/setup.c
@@ -0,0 +1,170 @@
+/*
+ * AmigaOne platform setup
+ *
+ * Copyright 2008 Gerhard Pircher (gerhard_pircher@gmx.net)
+ *
+ *   Based on original amigaone_setup.c source code
+ * Copyright 2003 by Hans-Joerg Frieden and Thomas Frieden
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/seq_file.h>
+#include <linux/utsrelease.h>
+
+#include <asm/machdep.h>
+#include <asm/cputable.h>
+#include <asm/prom.h>
+#include <asm/pci-bridge.h>
+#include <asm/i8259.h>
+#include <asm/time.h>
+#include <asm/udbg.h>
+
+extern void __flush_disable_L1(void);
+
+void amigaone_show_cpuinfo(struct seq_file *m)
+{
+        seq_printf(m, "vendor\t\t: Eyetech Ltd.\n");
+}
+
+static int __init amigaone_add_bridge(struct device_node *dev)
+{
+        const u32 *cfg_addr, *cfg_data;
+        int len;
+        const int *bus_range;
+        struct pci_controller *hose;
+
+        printk(KERN_INFO "Adding PCI host bridge %s\n", dev->full_name);
+
+        cfg_addr = of_get_address(dev, 0, NULL, NULL);
+        cfg_data = of_get_address(dev, 1, NULL, NULL);
+        if ((cfg_addr == NULL) || (cfg_data == NULL))
+                return -ENODEV;
+
+        bus_range = of_get_property(dev, "bus-range", &len);
+        if ((bus_range == NULL) || (len < 2 * sizeof(int)))
+                printk(KERN_WARNING "Can't get bus-range for %s, assume"
+                       " bus 0\n", dev->full_name);
+
+        hose = pcibios_alloc_controller(dev);
+        if (hose == NULL)
+                return -ENOMEM;
+
+        hose->first_busno = bus_range ? bus_range[0] : 0;
+        hose->last_busno = bus_range ? bus_range[1] : 0xff;
+
+        setup_indirect_pci(hose, cfg_addr[0], cfg_data[0], 0);
+
+        /* Interpret the "ranges" property */
+        /* This also maps the I/O region and sets isa_io/mem_base */
+        pci_process_bridge_OF_ranges(hose, dev, 1);
+
+        return 0;
+}
+
+void __init amigaone_setup_arch(void)
+{
+        struct device_node *np;
+        int phb = -ENODEV;
+
+        /* Lookup PCI host bridges. */
+        for_each_compatible_node(np, "pci", "mai-logic,articia-s")
+                phb = amigaone_add_bridge(np);
+
+        BUG_ON(phb != 0);
+
+        if (ppc_md.progress)
+                ppc_md.progress("Linux/PPC "UTS_RELEASE"\n", 0);
+}
+
+void __init amigaone_init_IRQ(void)
+{
+        struct device_node *pic, *np = NULL;
+        const unsigned long *prop = NULL;
+        unsigned long int_ack = 0;
+
+        /* Search for ISA interrupt controller. */
+        pic = of_find_compatible_node(NULL, "interrupt-controller",
+                                      "pnpPNP,000");
+        BUG_ON(pic == NULL);
+
+        /* Look for interrupt acknowledge address in the PCI root node. */
+        np = of_find_compatible_node(NULL, "pci", "mai-logic,articia-s");
+        if (np) {
+                prop = of_get_property(np, "8259-interrupt-acknowledge", NULL);
+                if (prop)
+                        int_ack = prop[0];
+                of_node_put(np);
+        }
+
+        if (int_ack == 0)
+                printk(KERN_WARNING "Cannot find PCI interrupt acknowledge"
+                       " address, polling\n");
+
+        i8259_init(pic, int_ack);
+        ppc_md.get_irq = i8259_irq;
+        irq_set_default_host(i8259_get_host());
+}
+
+void __init amigaone_init(void)
+{
+        request_region(0x00, 0x20, "dma1");
+        request_region(0x40, 0x20, "timer");
+        request_region(0x80, 0x10, "dma page reg");
+        request_region(0xc0, 0x20, "dma2");
+}
+
+void amigaone_restart(char *cmd)
+{
+        local_irq_disable();
+
+        /* Flush and disable caches. */
+        __flush_disable_L1();
+
+        /* Set SRR0 to the reset vector and turn on MSR_IP. */
+        mtspr(SPRN_SRR0, 0xfff00100);
+        mtspr(SPRN_SRR1, MSR_IP);
+
+        /* Do an rfi to jump back to firmware. */
+        __asm__ __volatile__("rfi" : : : "memory");
+
+        /* Not reached. */
+        while (1);
+}
+
+static int __init amigaone_probe(void)
+{
+        unsigned long root = of_get_flat_dt_root();
+
+        if (of_flat_dt_is_compatible(root, "eyetech,amigaone")) {
+                /*
+                 * Coherent memory access cause complete system lockup! Thus
+                 * disable this CPU feature, even if the CPU needs it.
+                 */
+                cur_cpu_spec->cpu_features &= ~CPU_FTR_NEED_COHERENT;
+
+                ISA_DMA_THRESHOLD = 0x00ffffff;
+                DMA_MODE_READ = 0x44;
+                DMA_MODE_WRITE = 0x48;
+
+                return 1;
+        }
+
+        return 0;
+}
+
+define_machine(amigaone) {
+        .name                   = "AmigaOne",
+        .probe                  = amigaone_probe,
+        .setup_arch             = amigaone_setup_arch,
+        .init                   = amigaone_init,
+        .show_cpuinfo           = amigaone_show_cpuinfo,
+        .init_IRQ               = amigaone_init_IRQ,
+        .restart                = amigaone_restart,
+        .calibrate_decr         = generic_calibrate_decr,
+        .progress               = udbg_progress,
+};