kvm tools: Add SPAPR PPC64 HV console

This adds the console code, plus VIO HV terminal nodes are added to
the device tree so the guest kernel will pick it up.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

Makefile

@@ -136,6 +136,7 @@ ifeq ($(uname_M), ppc64)
 	OBJS	+= powerpc/kvm-cpu.o
 	OBJS	+= powerpc/spapr_hcall.o
 	OBJS	+= powerpc/spapr_rtas.o
+	OBJS	+= powerpc/spapr_hvcons.o
 # We use libfdt, but it's sometimes not packaged 64bit.  It's small too,
 # so just build it in:
 	CFLAGS 	+= -I../../scripts/dtc/libfdt

powerpc/kvm.c

@@ -17,6 +17,7 @@
 #include "cpu_info.h"
 
 #include "spapr.h"
+#include "spapr_hvcons.h"
 
 #include <linux/kvm.h>
 
@@ -133,6 +134,8 @@ void kvm__arch_init(struct kvm *kvm, const char *hugetlbfs_path, u64 ram_size)
 	/* FIXME: SPAPR-specific */
 	hypercall_init();
 	register_core_rtas();
+	/* Now that hypercalls are initialised, register a couple for the console: */
+	spapr_hvcons_init();
 }
 
 void kvm__arch_delete_ram(struct kvm *kvm)
@@ -151,6 +154,12 @@ void kvm__irq_trigger(struct kvm *kvm, int irq)
 	kvm__irq_line(kvm, irq, 0);
 }
 
+void kvm__arch_periodic_poll(struct kvm *kvm)
+{
+	/* FIXME: Should register callbacks to platform-specific polls */
+	spapr_hvcons_poll(kvm);
+}
+
 int load_flat_binary(struct kvm *kvm, int fd_kernel, int fd_initrd, const char *kernel_cmdline)
 {
 	void *p;
@@ -266,6 +275,13 @@ static void setup_fdt(struct kvm *kvm)
 		_FDT(fdt_property(fdt, "linux,initrd-end",
 				   &ird_end_prop, sizeof(ird_end_prop)));
 	}
+
+	/*
+	 * stdout-path: This is assuming we're using the HV console.  Also, the
+	 * address is hardwired until we do a VIO bus.
+	 */
+	_FDT(fdt_property_string(fdt, "linux,stdout-path",
+				 "/vdevice/vty@30000000"));
 	_FDT(fdt_end_node(fdt));
 
 	/*
@@ -352,6 +368,23 @@ static void setup_fdt(struct kvm *kvm)
 	}
 	_FDT(fdt_end_node(fdt));
 
+	/*
+	 * VIO: See comment in linux,stdout-path; we don't yet represent a VIO
+	 * bus/address allocation so addresses are hardwired here.
+	 */
+	_FDT(fdt_begin_node(fdt, "vdevice"));
+	_FDT(fdt_property_cell(fdt, "#address-cells", 0x1));
+	_FDT(fdt_property_cell(fdt, "#size-cells", 0x0));
+	_FDT(fdt_property_string(fdt, "device_type", "vdevice"));
+	_FDT(fdt_property_string(fdt, "compatible", "IBM,vdevice"));
+	_FDT(fdt_begin_node(fdt, "vty@30000000"));
+	_FDT(fdt_property_string(fdt, "name", "vty"));
+	_FDT(fdt_property_string(fdt, "device_type", "serial"));
+	_FDT(fdt_property_string(fdt, "compatible", "hvterm1"));
+	_FDT(fdt_property_cell(fdt, "reg", 0x30000000));
+	_FDT(fdt_end_node(fdt));
+	_FDT(fdt_end_node(fdt));
+
 	/* Finalise: */
 	_FDT(fdt_end_node(fdt)); /* Root node */
 	_FDT(fdt_finish(fdt));

powerpc/spapr_hvcons.c

@@ -0,0 +1,102 @@
+/*
+ * SPAPR HV console
+ *
+ * Borrowed lightly from QEMU's spapr_vty.c, Copyright (c) 2010 David Gibson,
+ * IBM Corporation.
+ *
+ * Copyright (c) 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation.
+ *
+ * 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 "kvm/term.h"
+#include "kvm/kvm.h"
+#include "kvm/kvm-cpu.h"
+#include "kvm/util.h"
+#include "spapr.h"
+#include "spapr_hvcons.h"
+
+#include <stdio.h>
+#include <sys/uio.h>
+#include <errno.h>
+
+#include <linux/byteorder.h>
+
+union hv_chario {
+	struct {
+		uint64_t char0_7;
+		uint64_t char8_15;
+	} a;
+	uint8_t buf[16];
+};
+
+static unsigned long h_put_term_char(struct kvm_cpu *vcpu, unsigned long opcode, unsigned long *args)
+{
+	/* To do: Read register from args[0], and check it. */
+	unsigned long len = args[1];
+	union hv_chario data;
+	struct iovec iov;
+
+	if (len > 16) {
+		return H_PARAMETER;
+	}
+	data.a.char0_7 = cpu_to_be64(args[2]);
+	data.a.char8_15 = cpu_to_be64(args[3]);
+
+	iov.iov_base = data.buf;
+	iov.iov_len = len;
+	do {
+		int ret;
+
+		ret = term_putc_iov(CONSOLE_HV, &iov, 1, 0);
+		if (ret < 0) {
+			die("term_putc_iov error %d!\n", errno);
+		}
+		iov.iov_base += ret;
+		iov.iov_len -= ret;
+	} while (iov.iov_len > 0);
+
+	return H_SUCCESS;
+}
+
+
+static unsigned long h_get_term_char(struct kvm_cpu *vcpu, unsigned long opcode, unsigned long *args)
+{
+	/* To do: Read register from args[0], and check it. */
+	unsigned long *len = args + 0;
+	unsigned long *char0_7 = args + 1;
+	unsigned long *char8_15 = args + 2;
+	union hv_chario data;
+	struct iovec iov;
+
+	if (term_readable(CONSOLE_HV, 0)) {
+		iov.iov_base = data.buf;
+		iov.iov_len = 16;
+
+		*len = term_getc_iov(CONSOLE_HV, &iov, 1, 0);
+		*char0_7 = be64_to_cpu(data.a.char0_7);
+		*char8_15 = be64_to_cpu(data.a.char8_15);
+	} else {
+		*len = 0;
+	}
+
+	return H_SUCCESS;
+}
+
+void spapr_hvcons_poll(struct kvm *kvm)
+{
+	if (term_readable(CONSOLE_HV, 0)) {
+		/*
+		 * We can inject an IRQ to guest here if we want.  The guest
+		 * will happily poll, though, so not required.
+		 */
+	}
+}
+
+void spapr_hvcons_init(void)
+{
+	spapr_register_hypercall(H_PUT_TERM_CHAR, h_put_term_char);
+	spapr_register_hypercall(H_GET_TERM_CHAR, h_get_term_char);
+}

powerpc/spapr_hvcons.h

@@ -0,0 +1,19 @@
+/*
+ * SPAPR HV console
+ *
+ * Copyright (c) 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation.
+ *
+ * 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.
+ */
+
+#ifndef spapr_hvcons_H
+#define spapr_hvcons_H
+
+#include "kvm/kvm.h"
+
+void spapr_hvcons_init(void);
+void spapr_hvcons_poll(struct kvm *kvm);
+
+#endif