device/pci_ops: Define pci_find_capability() just once

Wrap the simple romstage implementation to be called
from ramstage.

Change-Id: Iadadf3d550416850d6c37233bd4eda025f4d3960
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31755
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/src/device/pci_ops.c b/src/device/pci_ops.c
index 34f9d1e5b5..96133155be 100644
--- a/src/device/pci_ops.c
+++ b/src/device/pci_ops.c
@@ -11,6 +11,77 @@
  * GNU General Public License for more details.
  */
 
+#define __SIMPLE_DEVICE__
+
 #include <stdint.h>
+#include <device/pci.h>
+#include <device/pci_def.h>
+#include <device/pci_ops.h>
+#include <device/pci_type.h>
 
 u8 *const pci_mmconf = (void *)(uintptr_t)CONFIG_MMCONF_BASE_ADDRESS;
+
+/**
+ * Given a device, a capability type, and a last position, return the next
+ * matching capability. Always start at the head of the list.
+ *
+ * @param dev Pointer to the device structure.
+ * @param cap PCI_CAP_LIST_ID of the PCI capability we're looking for.
+ * @param last Location of the PCI capability register to start from.
+ * @return The next matching capability.
+ */
+u16 pci_s_find_next_capability(pci_devfn_t dev, u16 cap, u16 last)
+{
+	u16 pos = 0;
+	u16 status;
+	int reps = 48;
+
+	status = pci_s_read_config16(dev, PCI_STATUS);
+	if (!(status & PCI_STATUS_CAP_LIST))
+		return 0;
+
+	u8 hdr_type = pci_s_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_s_read_config8(dev, pos);
+	while (reps-- && (pos >= 0x40)) { /* Loop through the linked list. */
+		int this_cap;
+
+		pos &= ~3;
+		this_cap = pci_s_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_s_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
+	}
+	return 0;
+}
+
+/**
+ * Given a device, and a capability type, return the next matching
+ * capability. Always start at the head of the list.
+ *
+ * @param dev Pointer to the device structure.
+ * @param cap PCI_CAP_LIST_ID of the PCI capability we're looking for.
+ * @return The next matching capability.
+ */
+u16 pci_s_find_capability(pci_devfn_t dev, u16 cap)
+{
+	return pci_s_find_next_capability(dev, cap, 0);
+}