superio/common: Add ssdtgen for generic SuperIOs

Add a generic SuperIO ACPI generator, dropping the need to include
additional code in DSDT for SuperIO.

It generates a device HID based on the decoded I/O range.

Tested on Supermicro X11SSH-TF using AST2400.
The SSDT contains no errors and all devices are present.

Possible TODOs:
* Add "enter config" and "exit config" bytes
* Generate support methods to enter and exit config mode
* Generate support methods to query, change or disable current
  resource settings on specific LDNs

Change-Id: I2716ae0580d68e5d4fcc484cb1648a2cdc1f4ca0
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33033
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

1 files changed, 247 insertions, 0 deletions

diff --git a/src/superio/common/ssdt.c b/src/superio/common/ssdt.c
new file mode 100644
index 0000000000..035f06a71e
--- /dev/null
+++ b/src/superio/common/ssdt.c
@@ -0,0 +1,247 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 <superio/common/ssdt.h>
+
+#include <device/device.h>
+#include <device/pnp.h>
+#include <arch/acpigen.h>
+#include <arch/acpi.h>
+#include <device/pnp_def.h>
+#include <console/console.h>
+#include <types.h>
+
+struct superio_dev {
+	const char *acpi_hid;
+	u16 io_base[4];
+	u8 irq[2];
+};
+
+static const struct superio_dev superio_devs[] = {
+	{ACPI_HID_FDC, {0x3f0, 0x3f2, 0x3f7}, {6, } },
+	{ACPI_HID_KEYBOARD, {60, 64, }, {1, } },
+	{ACPI_HID_MOUSE, {60, 64, }, {12, } },
+	{ACPI_HID_COM, {0x3f8, 0x2f8, 0x3e8, 0x2e8}, {4, 3} },
+	{ACPI_HID_LPT, {0x378, }, {7, } },
+};
+
+static const u8 io_idx[] = {PNP_IDX_IO0, PNP_IDX_IO1, PNP_IDX_IO2, PNP_IDX_IO3};
+static const u8 irq_idx[] = {PNP_IDX_IRQ0, PNP_IDX_IRQ1};
+
+static const struct superio_dev *superio_guess_function(struct device *dev)
+{
+	for (size_t i = 0; i < ARRAY_SIZE(io_idx); i++) {
+		struct resource *res = probe_resource(dev, io_idx[i]);
+		if (!res || !res->base)
+			continue;
+
+		for (size_t j = 0; j < ARRAY_SIZE(superio_devs); j++) {
+			for (size_t k = 0; k < 4; k++) {
+				if (!superio_devs[j].io_base[k])
+					continue;
+				if (superio_devs[j].io_base[k] == res->base)
+					return &superio_devs[j];
+			}
+		}
+	}
+	for (size_t i = 0; i < ARRAY_SIZE(irq_idx); i++) {
+		struct resource *res = probe_resource(dev, irq_idx[i]);
+		if (!res || !res->size)
+			continue;
+		for (size_t j = 0; j < ARRAY_SIZE(superio_devs); j++) {
+			for (size_t k = 0; k < 2; k++) {
+				if (!superio_devs[j].irq[k])
+					continue;
+				if (superio_devs[j].irq[k] == res->base)
+					return &superio_devs[j];
+			}
+		}
+	}
+	return NULL;
+}
+
+/* Return true if there are resources to report */
+static bool has_resources(struct device *dev)
+{
+	for (size_t i = 0; i < ARRAY_SIZE(io_idx); i++) {
+		struct resource *res = probe_resource(dev, io_idx[i]);
+		if (!res || !res->base || !res->size)
+			continue;
+		return 1;
+	}
+	for (size_t i = 0; i < ARRAY_SIZE(irq_idx); i++) {
+		struct resource *res = probe_resource(dev, irq_idx[i]);
+		if (!res || !res->size || res->base > 16)
+			continue;
+		return 1;
+	}
+	return 0;
+}
+
+/* Add IO and IRQ resources for _CRS or _PRS */
+static void ldn_gen_resources(struct device *dev)
+{
+	uint16_t irq = 0;
+	for (size_t i = 0; i < ARRAY_SIZE(io_idx); i++) {
+		struct resource *res = probe_resource(dev, io_idx[i]);
+		if (!res || !res->base)
+			continue;
+		resource_t base = res->base;
+		resource_t size = res->size;
+		while (size > 0) {
+			resource_t sz = size > 255 ? 255 : size;
+			/* TODO: Needs test with regions >= 256 bytes */
+			acpigen_write_io16(base, base, 1, sz, 1);
+			size -= sz;
+			base += sz;
+		}
+	}
+	for (size_t i = 0; i < ARRAY_SIZE(irq_idx); i++) {
+		struct resource *res = probe_resource(dev, irq_idx[i]);
+		if (!res || !res->size || res->base >= 16)
+			continue;
+		irq |= 1 << res->base;
+	}
+	if (irq)
+		acpigen_write_irq(irq);
+
+}
+
+/* Add resource base and size for additional SuperIO code */
+static void ldn_gen_resources_use(struct device *dev)
+{
+	char name[5];
+	for (size_t i = 0; i < ARRAY_SIZE(io_idx); i++) {
+		struct resource *res = probe_resource(dev, io_idx[i]);
+		if (!res || !res->base || !res->size)
+			continue;
+
+		snprintf(name, sizeof(name), "IO%XB", i);
+		name[4] = '\0';
+		acpigen_write_name_integer(name, res->base);
+
+		snprintf(name, sizeof(name), "IO%XS", i);
+		name[4] = '\0';
+		acpigen_write_name_integer(name, res->size);
+	}
+}
+
+const char *superio_common_ldn_acpi_name(const struct device *dev)
+{
+	u8 ldn = dev->path.pnp.device & 0xff;
+	u8 vldn = (dev->path.pnp.device >> 8) & 0x7;
+	static char name[5];
+
+	snprintf(name, sizeof(name), "L%02X%01X", ldn, vldn);
+
+	name[4] = '\0';
+
+	return name;
+}
+
+static const char *name_from_hid(const char *hid)
+{
+	static const struct {
+		const char *hid;
+		const char *name;
+	} lookup[] = {
+		{ACPI_HID_FDC, "FDC" },
+		{ACPI_HID_KEYBOARD, "PS2 Keyboard" },
+		{ACPI_HID_MOUSE, "PS2 Mouse"},
+		{ACPI_HID_COM, "COM port" },
+		{ACPI_HID_LPT, "LPT" },
+		{ACPI_HID_PNP, "Generic PNP device" },
+	};
+
+	for (size_t i = 0; hid && i < ARRAY_SIZE(lookup); i++) {
+		if (strcmp(hid, lookup[i].hid) == 0)
+			return lookup[i].name;
+	}
+	return "Generic device";
+}
+
+void superio_common_fill_ssdt_generator(struct device *dev)
+{
+	const char *scope = acpi_device_scope(dev);
+	const char *name = acpi_device_name(dev);
+	const u8 ldn = dev->path.pnp.device & 0xff;
+	const u8 vldn = (dev->path.pnp.device >> 8) & 0x7;
+	const char *hid;
+
+	if (!scope || !name) {
+		printk(BIOS_ERR, "%s: Missing ACPI path/scope\n", dev_path(dev));
+		return;
+	}
+	if (vldn) {
+		printk(BIOS_DEBUG, "%s: Ignoring virtual LDN\n", dev_path(dev));
+		return;
+	}
+
+	printk(BIOS_DEBUG, "%s.%s: %s\n", scope, name, dev_path(dev));
+
+	/* Scope */
+	acpigen_write_scope(scope);
+
+	/* Device */
+	acpigen_write_device(name);
+
+	acpigen_write_name_byte("_UID", 0);
+	acpigen_write_name_byte("LDN", ldn);
+	acpigen_write_name_byte("VLDN", vldn);
+
+	acpigen_write_STA(dev->enabled ? 0xf : 0);
+
+	if (!dev->enabled) {
+		acpigen_pop_len(); /* Device */
+		acpigen_pop_len(); /* Scope */
+		return;
+	}
+
+	if (has_resources(dev)) {
+		/* Resources - _CRS */
+		acpigen_write_name("_CRS");
+		acpigen_write_resourcetemplate_header();
+		ldn_gen_resources(dev);
+		acpigen_write_resourcetemplate_footer();
+
+		/* Resources - _PRS */
+		acpigen_write_name("_PRS");
+		acpigen_write_resourcetemplate_header();
+		ldn_gen_resources(dev);
+		acpigen_write_resourcetemplate_footer();
+
+		/* Resources base and size for 3rd party ACPI code */
+		ldn_gen_resources_use(dev);
+	}
+
+	hid = acpi_device_hid(dev);
+	if (!hid) {
+		printk(BIOS_ERR, "%s: SuperIO driver doesn't provide a _HID\n", dev_path(dev));
+		/* Try to guess it... */
+		const struct superio_dev *sdev = superio_guess_function(dev);
+		if (sdev && sdev->acpi_hid) {
+			hid = sdev->acpi_hid;
+			printk(BIOS_WARNING, "%s: Guessed _HID is '%s'\n", dev_path(dev), hid);
+		} else {
+			hid = ACPI_HID_PNP;
+			printk(BIOS_ERR, "%s: Failed to guessed _HID\n", dev_path(dev));
+		}
+	}
+
+	acpigen_write_name_string("_HID", hid);
+	acpigen_write_name_string("_DDN", name_from_hid(hid));
+
+	acpigen_pop_len(); /* Device */
+	acpigen_pop_len(); /* Scope */
+}