powerpc/e500: add paravirt QEMU platform

This gives the kernel a paravirtualized machine to target, without
requiring both sides to pretend to be targeting a specific board
that likely has little to do with the host in KVM scenarios.  This
avoids the need to add new boards to QEMU just to be able to
run KVM on new CPUs.

As this is the first platform that can run with either e500v2 or
e500mc, CONFIG_PPC_E500MC is now a legitimately user configurable
option, so add a help text.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/85xx/qemu_e500.c b/arch/powerpc/platforms/85xx/qemu_e500.c
new file mode 100644
index 000000000000..95a2e53af71b
--- /dev/null
+++ b/arch/powerpc/platforms/85xx/qemu_e500.c
@@ -0,0 +1,72 @@
+/*
+ * Paravirt target for a generic QEMU e500 machine
+ *
+ * This is intended to be a flexible device-tree-driven platform, not fixed
+ * to a particular piece of hardware or a particular spec of virtual hardware,
+ * beyond the assumption of an e500-family CPU.  Some things are still hardcoded
+ * here, such as MPIC, but this is a limitation of the current code rather than
+ * an interface contract with QEMU.
+ *
+ * Copyright 2012 Freescale Semiconductor Inc.
+ *
+ * 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/of_fdt.h>
+#include <asm/machdep.h>
+#include <asm/time.h>
+#include <asm/udbg.h>
+#include <asm/mpic.h>
+#include <sysdev/fsl_soc.h>
+#include <sysdev/fsl_pci.h>
+#include "smp.h"
+#include "mpc85xx.h"
+
+void __init qemu_e500_pic_init(void)
+{
+	struct mpic *mpic;
+
+	mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN | MPIC_SINGLE_DEST_CPU,
+			0, 256, " OpenPIC  ");
+
+	BUG_ON(mpic == NULL);
+	mpic_init(mpic);
+}
+
+static void __init qemu_e500_setup_arch(void)
+{
+	ppc_md.progress("qemu_e500_setup_arch()", 0);
+
+	fsl_pci_init();
+	mpc85xx_smp_init();
+}
+
+/*
+ * Called very early, device-tree isn't unflattened
+ */
+static int __init qemu_e500_probe(void)
+{
+	unsigned long root = of_get_flat_dt_root();
+
+	return !!of_flat_dt_is_compatible(root, "fsl,qemu-e500");
+}
+
+machine_device_initcall(qemu_e500, mpc85xx_common_publish_devices);
+
+define_machine(qemu_e500) {
+	.name			= "QEMU e500",
+	.probe			= qemu_e500_probe,
+	.setup_arch		= qemu_e500_setup_arch,
+	.init_IRQ		= qemu_e500_pic_init,
+#ifdef CONFIG_PCI
+	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
+#endif
+	.get_irq		= mpic_get_irq,
+	.restart		= fsl_rstcr_restart,
+	.calibrate_decr		= generic_calibrate_decr,
+	.progress		= udbg_progress,
+};