New patch to review for coreboot: 46d9957 usbdebug: Initialize EHCI Debug Port just once

[Kyösti Mälkki]

Kyösti Mälkki ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3476

-gerrit

commit 46d9957b457fa95d328278d0f8b85f74c6588aa6
Author: Aaron Durbin 
Date:   Sat Jun 15 14:56:20 2013 +0300

usbdebug: Initialize EHCI Debug Port just once

If we already initialized EHCI in romstage, locate current configuration
    from salvaged CAR_GLOBAL and avoid doing initialization second time.

The initialization sequence resets USB link and has been witnessed
    to cause troubles/disconnects when used with kernel USB gadget
    G_DBGP_SERIAL as the receiving party.

Change-Id: I7cb3a359488b25abc9de49c96c0197f6563a4a2c
    Signed-off-by: Kyösti Mälkki 
---
 src/lib/usbdebug.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/src/lib/usbdebug.c b/src/lib/usbdebug.c
index 0fdf221..ad02b6e 100644
--- a/src/lib/usbdebug.c
+++ b/src/lib/usbdebug.c
@@ -366,6 +366,33 @@ static int ehci_wait_for_port(struct ehci_regs *ehci_regs, int port)
    return -1; //-ENOTCONN;
 }

+#if !defined(__PRE_RAM__) && !defined(__SMM__)
+static int get_usbdebug_from_cbmem(struct ehci_debug_info *info)
+{
+	struct ehci_debug_info *dbg_info_cbmem;
+
+	dbg_info_cbmem = cbmem_find(CBMEM_ID_EHCI_DEBUG);
+
+	if (dbg_info_cbmem == NULL)
+		return -1;
+
+	printk(BIOS_DEBUG, "EHCI debug port found in cbmem.\n");
+
+	info->ehci_caps = dbg_info_cbmem->ehci_caps;
+	info->ehci_regs = dbg_info_cbmem->ehci_regs;
+	info->ehci_debug = dbg_info_cbmem->ehci_debug;
+	info->devnum = dbg_info_cbmem->devnum;
+	info->endpoint_out = dbg_info_cbmem->endpoint_out;
+	info->endpoint_in = dbg_info_cbmem->endpoint_in;
+
+	return 0;
+}
+#else
+static int get_usbdebug_from_cbmem(struct ehci_debug_info *info)
+{
+	return -1;
+}
+#endif

int usbdebug_init(unsigned ehci_bar, unsigned offset, struct ehci_debug_info *info)
 {
@@ -384,6 +411,9 @@ int usbdebug_init(unsigned ehci_bar, unsigned offset, struct ehci_debug_info *in
    int port_map_tried;
    int playtimes = 3;

+	if (!get_usbdebug_from_cbmem(info))
+		return 0;
+
    ehci_caps  = (struct ehci_caps *)ehci_bar;
    ehci_regs  = (struct ehci_regs *)(ehci_bar +
    		HC_LENGTH(read32((unsigned long)&ehci_caps->hc_capbase)));