uio_usbdebug: User-space-i/o framework for usbdebug

uio_usbdebug enables you to debug coreboot's usbdebug driver inside a
running operating system (only Linux at this time). This comes very
handy if you're hacking the usbdebug driver and don't have any other
debug output from coreboot itself.

Currently, only Intel chipsets are supported.

Change-Id: Iaf0bcd4b4c01ae0b099d1206d553344054a62f31
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: http://review.coreboot.org/4695
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/util/uio_usbdebug/drivers/usb/pci_ehci.c b/util/uio_usbdebug/drivers/usb/pci_ehci.c
new file mode 100644
index 000000000000..6a316a7983b2
--- /dev/null
+++ b/util/uio_usbdebug/drivers/usb/pci_ehci.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2014 Nico Huber <nico.h@gmx.de>
+ *
+ * Code borrowed from pci_early.c:
+ *   Copyright (C) 2011 Google 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; version 2 of the License.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
+ */
+
+#include <device/pci_ehci.h>
+
+static unsigned pci_find_next_capability(pci_devfn_t dev, unsigned cap, unsigned last)
+{
+	unsigned pos = 0;
+	u16 status;
+	unsigned reps = 48;
+
+	status = pci_read_config16(dev, PCI_STATUS);
+	if (!(status & PCI_STATUS_CAP_LIST))
+		return 0;
+
+	u8 hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
+	switch (hdr_type & 0x7f) {
+	case PCI_HEADER_TYPE_NORMAL:
+	case PCI_HEADER_TYPE_BRIDGE:
+		pos = PCI_CAPABILITY_LIST;
+		break;
+	case PCI_HEADER_TYPE_CARDBUS:
+		pos = PCI_CB_CAPABILITY_LIST;
+		break;
+	default:
+		return 0;
+	}
+
+	pos = pci_read_config8(dev, pos);
+	while (reps-- && (pos >= 0x40)) { /* Loop through the linked list. */
+		unsigned this_cap;
+
+		pos &= ~3;
+		this_cap = pci_read_config8(dev, pos + PCI_CAP_LIST_ID);
+		if (this_cap == 0xff)
+			break;
+
+		if (!last && (this_cap == cap))
+			return pos;
+
+		if (last == pos)
+			last = 0;
+
+		pos = pci_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
+	}
+	return 0;
+}
+
+static unsigned pci_find_capability(pci_devfn_t dev, unsigned cap)
+{
+	return pci_find_next_capability(dev, cap, 0);
+}
+
+extern void *ehci_bar;
+int ehci_debug_hw_enable(unsigned int *base, unsigned int *dbg_offset)
+{
+	pci_devfn_t dbg_dev = pci_ehci_dbg_dev(CONFIG_USBDEBUG_HCD_INDEX);
+	pci_ehci_dbg_enable(dbg_dev, CONFIG_EHCI_BAR);
+	pci_devfn_t dev = dbg_dev;
+
+	u8 pos = pci_find_capability(dev, PCI_CAP_ID_EHCI_DEBUG);
+	if (!pos)
+		return -1;
+
+	u32 cap = pci_read_config32(dev, pos);
+
+	/* FIXME: We should remove static EHCI_BAR_INDEX. */
+	u8 dbg_bar = 0x10 + 4 * ((cap >> 29) - 1);
+	if (dbg_bar != EHCI_BAR_INDEX)
+		return -1;
+
+	*base = (u32)ehci_bar;
+	*dbg_offset = (cap>>16) & 0x1ffc;
+	return 0;
+}
+
+void ehci_debug_select_port(unsigned int port)
+{
+	pci_devfn_t dbg_dev = pci_ehci_dbg_dev(CONFIG_USBDEBUG_HCD_INDEX);
+	pci_ehci_dbg_set_port(dbg_dev, port);
+}