[PATCH 090/108] x86: apl: Add support for hostbridge ACPI generation

[Simon Glass]

Support generating a DMAR table and add a few helper routines as well.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 arch/x86/cpu/apollolake/hostbridge.c          | 104 ++++++++++++++++++
 .../include/asm/arch-apollolake/systemagent.h |   6 +
 2 files changed, 110 insertions(+)

diff --git a/arch/x86/cpu/apollolake/hostbridge.c b/arch/x86/cpu/apollolake/hostbridge.c
index 793853d5b5..5616d89950 100644
--- a/arch/x86/cpu/apollolake/hostbridge.c
+++ b/arch/x86/cpu/apollolake/hostbridge.c
@@ -1,16 +1,29 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright 2019 Google LLC
+ * Copyright (C) 2015 - 2017 Intel Corp.
+ * Copyright (C) 2017 - 2019 Siemens AG
+ * (Written by Alexandru Gagniuc <alexandrux.gagniuc at intel.com> for Intel Corp.)
+ * (Written by Andrey Petrov <andrey.petrov at intel.com> for Intel Corp.)
+ *
+ * Portions from coreboot soc/intel/apollolake/chip.c
  */
 
+#define LOG_CATEGORY UCLASS_NORTHBRIDGE
+
 #include <common.h>
+#include <acpi_table.h>
 #include <dm.h>
 #include <dt-structs.h>
 #include <spl.h>
+#include <tables_csum.h>
 #include <asm/intel_pinctrl.h>
 #include <asm/intel_regs.h>
+#include <asm/io.h>
 #include <asm/pci.h>
+#include <asm/arch/acpi.h>
 #include <asm/arch/systemagent.h>
+#include <dm/acpi.h>
 
 /**
  * struct apl_hostbridge_platdata - platform data for hostbridge
@@ -39,7 +52,9 @@ enum {
 
 	PCIEXBAR_PCIEXBAREN	= 1 << 0,
 
+	BGSM			= 0xb4,  /* Base GTT Stolen Memory */
 	TSEG			= 0xb8,  /* TSEG base */
+	TOLUD			= 0xbc,
 };
 
 static int apl_hostbridge_early_init_pinctrl(struct udevice *dev)
@@ -164,6 +179,92 @@ static int apl_hostbridge_probe(struct udevice *dev)
 	return 0;
 }
 
+static int apl_acpi_hb_get_name(const struct udevice *dev, char *out_name)
+{
+	return acpi_return_name(out_name, "RHUB");
+}
+
+static int apl_acpi_hb_write_tables(const struct udevice *dev,
+				    struct acpi_ctx *ctx)
+{
+	struct acpi_table_header *header;
+	struct acpi_dmar *dmar;
+	u32 val;
+
+	/*
+	 * Create DMAR table only if virtualization is enabled. Due to some
+	 * constraints on Apollo Lake SoC (some stepping affected), VTD could
+	 * not be enabled together with IPU. Doing so will override and disable
+	 * VTD while leaving CAPID0_A still reporting that VTD is available.
+	 * As in this case FSP will lock VTD to disabled state, we need to make
+	 * sure that DMAR table generation only happens when at least DEFVTBAR
+	 * is enabled. Otherwise the DMAR header will be generated while the
+	 * content of the table will be missing.
+	 */
+
+	dm_pci_read_config32(dev, CAPID0_A, &val);
+	if ((val & VTD_DISABLE) ||
+	    !(readl(MCHBAR_REG(DEFVTBAR)) & VTBAR_ENABLED))
+		return 0;
+
+	log_debug("ACPI:    * DMAR\n");
+	dmar = (struct acpi_dmar *)ctx->current;
+	header = &dmar->header;
+	acpi_create_dmar(dmar, DMAR_INTR_REMAP);
+	ctx->current += sizeof(struct acpi_dmar);
+	apl_acpi_fill_dmar(ctx);
+
+	/* (Re)calculate length and checksum */
+	header->length = ctx->current - (void *)dmar;
+	header->checksum = table_compute_checksum((void *)dmar, header->length);
+
+	acpi_align(ctx);
+	acpi_add_table(ctx, dmar);
+	acpi_align(ctx);
+
+	return 0;
+}
+
+static int apl_hostbridge_remove(struct udevice *dev)
+{
+	/*
+	 * TODO(sjg at chromium.org): Consider adding code from coreboot's
+	 * platform_fsp_notify_status()
+	 */
+
+	return 0;
+}
+
+static ulong sa_read_reg(struct udevice *dev, int reg)
+{
+	u32 val;
+
+	/* All regions concerned for have 1 MiB alignment */
+	dm_pci_read_config32(dev, BGSM, &val);
+
+	return ALIGN_DOWN(val, 1 << 20);
+}
+
+ulong sa_get_tolud_base(struct udevice *dev)
+{
+	return sa_read_reg(dev, TOLUD);
+}
+
+ulong sa_get_gsm_base(struct udevice *dev)
+{
+	return sa_read_reg(dev, BGSM);
+}
+
+ulong sa_get_tseg_base(struct udevice *dev)
+{
+	return sa_read_reg(dev, TSEG);
+}
+
+struct acpi_ops apl_hostbridge_acpi_ops = {
+	.get_name	= apl_acpi_hb_get_name,
+	.write_tables	= apl_acpi_hb_write_tables,
+};
+
 static const struct udevice_id apl_hostbridge_ids[] = {
 	{ .compatible = "intel,apl-hostbridge" },
 	{ }
@@ -175,5 +276,8 @@ U_BOOT_DRIVER(apl_hostbridge_drv) = {
 	.of_match	= apl_hostbridge_ids,
 	.ofdata_to_platdata = apl_hostbridge_ofdata_to_platdata,
 	.probe		= apl_hostbridge_probe,
+	.remove		= apl_hostbridge_remove,
 	.platdata_auto_alloc_size = sizeof(struct apl_hostbridge_platdata),
+	acpi_ops_ptr(&apl_hostbridge_acpi_ops)
+	.flags		= DM_FLAG_OS_PREPARE,
 };
diff --git a/arch/x86/include/asm/arch-apollolake/systemagent.h b/arch/x86/include/asm/arch-apollolake/systemagent.h
index 206d8903fa..1553ec1cf4 100644
--- a/arch/x86/include/asm/arch-apollolake/systemagent.h
+++ b/arch/x86/include/asm/arch-apollolake/systemagent.h
@@ -34,4 +34,10 @@
  */
 void enable_bios_reset_cpl(void);
 
+/* API to get TOLUD base address */
+uintptr_t sa_get_tolud_base(struct udevice *dev);
+/* API to get GSM base address */
+ulong sa_get_gsm_base(struct udevice *dev);
+ulong sa_get_tseg_base(struct udevice *dev);
+
 #endif
-- 
2.25.0.341.g760bfbb309-goog