drivers/cavium: Add UART PCI driver

Add UART PCI driver in cavium/common/pci.

Tested on opencellular/elgon.
The UART is still initialized and usable in Linux.

Change-Id: I0fa2f086aba9b4f9c6dba7a35a84ea61c5fa64e4
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/30608
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

src/include/device/pci_ids.h

@@ -132,6 +132,9 @@
 #define PCI_DEVICE_ID_BERKOM_A4T		0xffa4
 #define PCI_DEVICE_ID_BERKOM_SCITEL_QUADRO	0xffa8
 
+#define PCI_VENDOR_CAVIUM			0x177d
+#define PCI_DEVICE_ID_CAVIUM_THUNDERX_UART	0xa00f
+
 #define PCI_VENDOR_ID_COMPAQ		0x0e11
 #define PCI_DEVICE_ID_COMPAQ_TOKENRING	0x0508
 #define PCI_DEVICE_ID_COMPAQ_1280	0x3033

src/soc/cavium/cn81xx/soc.c

@@ -381,18 +381,6 @@ static void soc_init(struct device *dev)
 		}
 	}
 
-	/* Init UARTs */
-	size_t i;
-	struct device *uart_dev;
-	for (i = 0; i <= 3; i++) {
-		uart_dev = dev_find_slot(1, PCI_DEVFN(8, i));
-		/* using device enable state from devicetree.cb */
-		if (uart_dev && uart_dev->enabled) {
-			if (!uart_is_enabled(i))
-				uart_setup(i, 0);
-		}
-	}
-
 	if (IS_ENABLED(CONFIG_ARM64_USE_ARM_TRUSTED_FIRMWARE))
 		soc_init_atf();
 }

src/soc/cavium/common/Makefile.inc

@@ -15,6 +15,8 @@
 
 ifeq ($(CONFIG_SOC_CAVIUM_COMMON),y)
 
+subdirs-y += pci
+
 CFLAGS_arm64   += -Wstack-usage=$(CONFIG_STACK_SIZE)
 
 bootblock-$(CONFIG_BOOTBLOCK_CUSTOM) += bootblock.c

src/soc/cavium/common/pci/Makefile.inc

@@ -0,0 +1 @@
+ramstage-y += uart.c

src/soc/cavium/common/pci/uart.c

@@ -0,0 +1,40 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2019 9Elements GmbH <patrick.rudolph@9elements.com>
+ *
+ * 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.
+ *
+ */
+
+#include <device/device.h>
+#include <soc/uart.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+
+static void cavium_uart_init(struct device *dev)
+{
+	const u8 fn = PCI_FUNC(dev->path.pci.devfn);
+
+	/* Calling uart_setup with no baudrate will do minimal HW init
+	 * enough for the kernel to not panic */
+	if (!uart_is_enabled(fn))
+		uart_setup(fn, 0);
+}
+
+static struct device_operations device_ops = {
+	.init = cavium_uart_init,
+};
+
+static const struct pci_driver soc_cavium_uart __pci_driver = {
+	.ops    = &device_ops,
+	.vendor = PCI_VENDOR_CAVIUM,
+	.device = PCI_DEVICE_ID_CAVIUM_THUNDERX_UART,
+};