x86: apl: Support writing the IntelGraphicsMem table

This table is needed by the Linux graphics driver to handle graphics
correctly. Write it to ACPI.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/intel_common/intel_opregion.c b/arch/x86/cpu/intel_common/intel_opregion.c
new file mode 100644
index 0000000..4e6c64d
--- /dev/null
+++ b/arch/x86/cpu/intel_common/intel_opregion.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Writing IntelGraphicsMem table for ACPI
+ *
+ * Copyright 2019 Google LLC
+ * Modified from coreboot src/soc/intel/gma/opregion.c
+ */
+
+#include <common.h>
+#include <binman.h>
+#include <bloblist.h>
+#include <dm.h>
+#include <spi_flash.h>
+#include <asm/intel_opregion.h>
+
+static char vbt_data[8 << 10];
+
+static int locate_vbt(char **vbtp, int *sizep)
+{
+	struct binman_entry vbt;
+	struct udevice *dev;
+	u32 vbtsig = 0;
+	int size;
+	int ret;
+
+	ret = binman_entry_find("intel-vbt", &vbt);
+	if (ret)
+		return log_msg_ret("find VBT", ret);
+	ret = uclass_first_device_err(UCLASS_SPI_FLASH, &dev);
+	if (ret)
+		return log_msg_ret("find flash", ret);
+	size = vbt.size;
+	if (size > sizeof(vbt_data))
+		return log_msg_ret("vbt", -E2BIG);
+	ret = spi_flash_read_dm(dev, vbt.image_pos, size, vbt_data);
+	if (ret)
+		return log_msg_ret("read", ret);
+
+	memcpy(&vbtsig, vbt_data, sizeof(vbtsig));
+	if (vbtsig != VBT_SIGNATURE) {
+		log_err("Missing/invalid signature in VBT data file!\n");
+		return -EINVAL;
+	}
+
+	log_info("Found a VBT of %u bytes\n", size);
+	*sizep = size;
+	*vbtp = vbt_data;
+
+	return 0;
+}
+
+/* Write ASLS PCI register and prepare SWSCI register */
+static int intel_gma_opregion_register(struct udevice *dev, ulong opregion)
+{
+	int sci_reg;
+
+	if (!device_active(dev))
+		return -ENOENT;
+
+	/*
+	 * Intel BIOS Specification
+	 * Chapter 5.3.7 "Initialise Hardware State"
+	 */
+	dm_pci_write_config32(dev, ASLS, opregion);
+
+	/*
+	 * Atom-based platforms use a combined SMI/SCI register,
+	 * whereas non-Atom platforms use a separate SCI register
+	 */
+	if (IS_ENABLED(CONFIG_INTEL_GMA_SWSMISCI))
+		sci_reg = SWSMISCI;
+	else
+		sci_reg = SWSCI;
+
+	/*
+	 * Intel's Windows driver relies on this:
+	 * Intel BIOS Specification
+	 * Chapter 5.4 "ASL Software SCI Handler"
+	 */
+	dm_pci_clrset_config16(dev, sci_reg, GSSCIE, SMISCISEL);
+
+	return 0;
+}
+
+int intel_gma_init_igd_opregion(struct udevice *dev,
+				struct igd_opregion *opregion)
+{
+	struct optionrom_vbt *vbt = NULL;
+	char *vbt_buf;
+	int vbt_size;
+	int ret;
+
+	ret = locate_vbt(&vbt_buf, &vbt_size);
+	if (ret) {
+		log_err("GMA: VBT couldn't be found\n");
+		return log_msg_ret("find vbt", ret);
+	}
+	vbt = (struct optionrom_vbt *)vbt_buf;
+
+	memset(opregion, '\0', sizeof(struct igd_opregion));
+
+	memcpy(&opregion->header.signature, IGD_OPREGION_SIGNATURE,
+	       sizeof(opregion->header.signature));
+	memcpy(opregion->header.vbios_version, vbt->coreblock_biosbuild,
+	       ARRAY_SIZE(vbt->coreblock_biosbuild));
+	/* Extended VBT support */
+	if (vbt->hdr_vbt_size > sizeof(opregion->vbt.gvd1)) {
+		struct optionrom_vbt *ext_vbt;
+
+		ret = bloblist_ensure_size(BLOBLISTT_INTEL_VBT,
+					   vbt->hdr_vbt_size,
+					   (void **)&ext_vbt);
+		if (ret) {
+			log_err("GMA: Unable to add Ext VBT to bloblist\n");
+			return log_msg_ret("blob", ret);
+		}
+
+		memcpy(ext_vbt, vbt, vbt->hdr_vbt_size);
+		opregion->mailbox3.rvda = (uintptr_t)ext_vbt;
+		opregion->mailbox3.rvds = vbt->hdr_vbt_size;
+	} else {
+		/* Raw VBT size which can fit in gvd1 */
+		printf("copy to %p\n", opregion->vbt.gvd1);
+		memcpy(opregion->vbt.gvd1, vbt, vbt->hdr_vbt_size);
+	}
+
+	/* 8kb */
+	opregion->header.size = sizeof(struct igd_opregion) / 1024;
+
+	/*
+	 * Left-shift version field to accommodate Intel Windows driver quirk
+	 * when not using a VBIOS.
+	 * Required for Legacy boot + NGI, UEFI + NGI, and UEFI + GOP driver.
+	 *
+	 * No adverse effects when using VBIOS or booting Linux.
+	 */
+	opregion->header.version = IGD_OPREGION_VERSION << 24;
+
+	/* We just assume we're mobile for now */
+	opregion->header.mailboxes = MAILBOXES_MOBILE;
+
+	/* Initialise Mailbox 1 */
+	opregion->mailbox1.clid = 1;
+
+	/* Initialise Mailbox 3 */
+	opregion->mailbox3.bclp = IGD_BACKLIGHT_BRIGHTNESS;
+	opregion->mailbox3.pfit = IGD_FIELD_VALID | IGD_PFIT_STRETCH;
+	opregion->mailbox3.pcft = 0; /* should be (IMON << 1) & 0x3e */
+	opregion->mailbox3.cblv = IGD_FIELD_VALID | IGD_INITIAL_BRIGHTNESS;
+	opregion->mailbox3.bclm[0] = IGD_WORD_FIELD_VALID + 0x0000;
+	opregion->mailbox3.bclm[1] = IGD_WORD_FIELD_VALID + 0x0a19;
+	opregion->mailbox3.bclm[2] = IGD_WORD_FIELD_VALID + 0x1433;
+	opregion->mailbox3.bclm[3] = IGD_WORD_FIELD_VALID + 0x1e4c;
+	opregion->mailbox3.bclm[4] = IGD_WORD_FIELD_VALID + 0x2866;
+	opregion->mailbox3.bclm[5] = IGD_WORD_FIELD_VALID + 0x327f;
+	opregion->mailbox3.bclm[6] = IGD_WORD_FIELD_VALID + 0x3c99;
+	opregion->mailbox3.bclm[7] = IGD_WORD_FIELD_VALID + 0x46b2;
+	opregion->mailbox3.bclm[8] = IGD_WORD_FIELD_VALID + 0x50cc;
+	opregion->mailbox3.bclm[9] = IGD_WORD_FIELD_VALID + 0x5ae5;
+	opregion->mailbox3.bclm[10] = IGD_WORD_FIELD_VALID + 0x64ff;
+
+	/* Write ASLS PCI register and prepare SWSCI register */
+	ret = intel_gma_opregion_register(dev, (ulong)opregion);
+	if (ret)
+		return log_msg_ret("write asls", ret);
+
+	return 0;
+}