v4.19.13 snapshot.
diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
new file mode 100644
index 0000000..7d4e5c0
--- /dev/null
+++ b/drivers/ide/ide-acpi.c
@@ -0,0 +1,622 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Provides ACPI support for IDE drives.
+ *
+ * Copyright (C) 2005 Intel Corp.
+ * Copyright (C) 2005 Randy Dunlap
+ * Copyright (C) 2006 SUSE Linux Products GmbH
+ * Copyright (C) 2006 Hannes Reinecke
+ */
+
+#include <linux/acpi.h>
+#include <linux/ata.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/ide.h>
+#include <linux/pci.h>
+#include <linux/dmi.h>
+#include <linux/module.h>
+
+#define REGS_PER_GTF		7
+
+struct GTM_buffer {
+	u32	PIO_speed0;
+	u32	DMA_speed0;
+	u32	PIO_speed1;
+	u32	DMA_speed1;
+	u32	GTM_flags;
+};
+
+struct ide_acpi_drive_link {
+	acpi_handle	 obj_handle;
+	u8		 idbuff[512];
+};
+
+struct ide_acpi_hwif_link {
+	ide_hwif_t			*hwif;
+	acpi_handle			 obj_handle;
+	struct GTM_buffer		 gtm;
+	struct ide_acpi_drive_link	 master;
+	struct ide_acpi_drive_link	 slave;
+};
+
+#undef DEBUGGING
+/* note: adds function name and KERN_DEBUG */
+#ifdef DEBUGGING
+#define DEBPRINT(fmt, args...)	\
+		printk(KERN_DEBUG "%s: " fmt, __func__, ## args)
+#else
+#define DEBPRINT(fmt, args...)	do {} while (0)
+#endif	/* DEBUGGING */
+
+static bool ide_noacpi;
+module_param_named(noacpi, ide_noacpi, bool, 0);
+MODULE_PARM_DESC(noacpi, "disable IDE ACPI support");
+
+static bool ide_acpigtf;
+module_param_named(acpigtf, ide_acpigtf, bool, 0);
+MODULE_PARM_DESC(acpigtf, "enable IDE ACPI _GTF support");
+
+static bool ide_acpionboot;
+module_param_named(acpionboot, ide_acpionboot, bool, 0);
+MODULE_PARM_DESC(acpionboot, "call IDE ACPI methods on boot");
+
+static bool ide_noacpi_psx;
+static int no_acpi_psx(const struct dmi_system_id *id)
+{
+	ide_noacpi_psx = true;
+	printk(KERN_NOTICE"%s detected - disable ACPI _PSx.\n", id->ident);
+	return 0;
+}
+
+static const struct dmi_system_id ide_acpi_dmi_table[] = {
+	/* Bug 9673. */
+	/* We should check if this is because ACPI NVS isn't save/restored. */
+	{
+		.callback = no_acpi_psx,
+		.ident    = "HP nx9005",
+		.matches  = {
+			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies Ltd."),
+			DMI_MATCH(DMI_BIOS_VERSION, "KAM1.60")
+		},
+	},
+
+	{ }	/* terminate list */
+};
+
+int ide_acpi_init(void)
+{
+	dmi_check_system(ide_acpi_dmi_table);
+	return 0;
+}
+
+bool ide_port_acpi(ide_hwif_t *hwif)
+{
+	return ide_noacpi == 0 && hwif->acpidata;
+}
+
+static acpi_handle acpi_get_child(acpi_handle handle, u64 addr)
+{
+	struct acpi_device *adev;
+
+	if (!handle || acpi_bus_get_device(handle, &adev))
+		return NULL;
+
+	adev = acpi_find_child_device(adev, addr, false);
+	return adev ? adev->handle : NULL;
+}
+
+/**
+ * ide_get_dev_handle - finds acpi_handle and PCI device.function
+ * @dev: device to locate
+ * @handle: returned acpi_handle for @dev
+ * @pcidevfn: return PCI device.func for @dev
+ *
+ * Returns the ACPI object handle to the corresponding PCI device.
+ *
+ * Returns 0 on success, <0 on error.
+ */
+static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
+			       u64 *pcidevfn)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	unsigned int bus, devnum, func;
+	u64 addr;
+	acpi_handle dev_handle;
+	acpi_status status;
+	struct acpi_device_info	*dinfo = NULL;
+	int ret = -ENODEV;
+
+	bus = pdev->bus->number;
+	devnum = PCI_SLOT(pdev->devfn);
+	func = PCI_FUNC(pdev->devfn);
+	/* ACPI _ADR encoding for PCI bus: */
+	addr = (u64)(devnum << 16 | func);
+
+	DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
+
+	dev_handle = ACPI_HANDLE(dev);
+	if (!dev_handle) {
+		DEBPRINT("no acpi handle for device\n");
+		goto err;
+	}
+
+	status = acpi_get_object_info(dev_handle, &dinfo);
+	if (ACPI_FAILURE(status)) {
+		DEBPRINT("get_object_info for device failed\n");
+		goto err;
+	}
+	if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
+	    dinfo->address == addr) {
+		*pcidevfn = addr;
+		*handle = dev_handle;
+	} else {
+		DEBPRINT("get_object_info for device has wrong "
+			" address: %llu, should be %u\n",
+			dinfo ? (unsigned long long)dinfo->address : -1ULL,
+			(unsigned int)addr);
+		goto err;
+	}
+
+	DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
+		 devnum, func, (unsigned long long)addr, *handle);
+	ret = 0;
+err:
+	kfree(dinfo);
+	return ret;
+}
+
+/**
+ * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
+ * @hwif: device to locate
+ *
+ * Retrieves the object handle for a given hwif.
+ *
+ * Returns handle on success, 0 on error.
+ */
+static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
+{
+	struct device		*dev = hwif->gendev.parent;
+	acpi_handle		uninitialized_var(dev_handle);
+	u64			pcidevfn;
+	acpi_handle		chan_handle;
+	int			err;
+
+	DEBPRINT("ENTER: device %s\n", hwif->name);
+
+	if (!dev) {
+		DEBPRINT("no PCI device for %s\n", hwif->name);
+		return NULL;
+	}
+
+	err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
+	if (err < 0) {
+		DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
+		return NULL;
+	}
+
+	/* get child objects of dev_handle == channel objects,
+	 * + _their_ children == drive objects */
+	/* channel is hwif->channel */
+	chan_handle = acpi_get_child(dev_handle, hwif->channel);
+	DEBPRINT("chan adr=%d: handle=0x%p\n",
+		 hwif->channel, chan_handle);
+
+	return chan_handle;
+}
+
+/**
+ * do_drive_get_GTF - get the drive bootup default taskfile settings
+ * @drive: the drive for which the taskfile settings should be retrieved
+ * @gtf_length: number of bytes of _GTF data returned at @gtf_address
+ * @gtf_address: buffer containing _GTF taskfile arrays
+ *
+ * The _GTF method has no input parameters.
+ * It returns a variable number of register set values (registers
+ * hex 1F1..1F7, taskfiles).
+ * The <variable number> is not known in advance, so have ACPI-CA
+ * allocate the buffer as needed and return it, then free it later.
+ *
+ * The returned @gtf_length and @gtf_address are only valid if the
+ * function return value is 0.
+ */
+static int do_drive_get_GTF(ide_drive_t *drive,
+		     unsigned int *gtf_length, unsigned long *gtf_address,
+		     unsigned long *obj_loc)
+{
+	acpi_status			status;
+	struct acpi_buffer		output;
+	union acpi_object 		*out_obj;
+	int				err = -ENODEV;
+
+	*gtf_length = 0;
+	*gtf_address = 0UL;
+	*obj_loc = 0UL;
+
+	if (!drive->acpidata->obj_handle) {
+		DEBPRINT("No ACPI object found for %s\n", drive->name);
+		goto out;
+	}
+
+	/* Setting up output buffer */
+	output.length = ACPI_ALLOCATE_BUFFER;
+	output.pointer = NULL;	/* ACPI-CA sets this; save/free it later */
+
+	/* _GTF has no input parameters */
+	err = -EIO;
+	status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
+				      NULL, &output);
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_DEBUG
+		       "%s: Run _GTF error: status = 0x%x\n",
+		       __func__, status);
+		goto out;
+	}
+
+	if (!output.length || !output.pointer) {
+		DEBPRINT("Run _GTF: "
+		       "length or ptr is NULL (0x%llx, 0x%p)\n",
+		       (unsigned long long)output.length,
+		       output.pointer);
+		goto out;
+	}
+
+	out_obj = output.pointer;
+	if (out_obj->type != ACPI_TYPE_BUFFER) {
+		DEBPRINT("Run _GTF: error: "
+		       "expected object type of ACPI_TYPE_BUFFER, "
+		       "got 0x%x\n", out_obj->type);
+		err = -ENOENT;
+		kfree(output.pointer);
+		goto out;
+	}
+
+	if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
+	    out_obj->buffer.length % REGS_PER_GTF) {
+		printk(KERN_ERR
+		       "%s: unexpected GTF length (%d) or addr (0x%p)\n",
+		       __func__, out_obj->buffer.length,
+		       out_obj->buffer.pointer);
+		err = -ENOENT;
+		kfree(output.pointer);
+		goto out;
+	}
+
+	*gtf_length = out_obj->buffer.length;
+	*gtf_address = (unsigned long)out_obj->buffer.pointer;
+	*obj_loc = (unsigned long)out_obj;
+	DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
+		 *gtf_length, *gtf_address, *obj_loc);
+	err = 0;
+out:
+	return err;
+}
+
+/**
+ * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
+ * @drive: the drive to which the taskfile command should be sent
+ * @gtf_length: total number of bytes of _GTF taskfiles
+ * @gtf_address: location of _GTF taskfile arrays
+ *
+ * Write {gtf_address, length gtf_length} in groups of
+ * REGS_PER_GTF bytes.
+ */
+static int do_drive_set_taskfiles(ide_drive_t *drive,
+				  unsigned int gtf_length,
+				  unsigned long gtf_address)
+{
+	int			rc = 0, err;
+	int			gtf_count = gtf_length / REGS_PER_GTF;
+	int			ix;
+
+	DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
+		 gtf_length, gtf_length, gtf_count, gtf_address);
+
+	/* send all taskfile registers (0x1f1-0x1f7) *in*that*order* */
+	for (ix = 0; ix < gtf_count; ix++) {
+		u8 *gtf = (u8 *)(gtf_address + ix * REGS_PER_GTF);
+		struct ide_cmd cmd;
+
+		DEBPRINT("(0x1f1-1f7): "
+			 "hex: %02x %02x %02x %02x %02x %02x %02x\n",
+			 gtf[0], gtf[1], gtf[2],
+			 gtf[3], gtf[4], gtf[5], gtf[6]);
+
+		if (!ide_acpigtf) {
+			DEBPRINT("_GTF execution disabled\n");
+			continue;
+		}
+
+		/* convert GTF to taskfile */
+		memset(&cmd, 0, sizeof(cmd));
+		memcpy(&cmd.tf.feature, gtf, REGS_PER_GTF);
+		cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
+		cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
+
+		err = ide_no_data_taskfile(drive, &cmd);
+		if (err) {
+			printk(KERN_ERR "%s: ide_no_data_taskfile failed: %u\n",
+					__func__, err);
+			rc = err;
+		}
+	}
+
+	return rc;
+}
+
+/**
+ * ide_acpi_exec_tfs - get then write drive taskfile settings
+ * @drive: the drive for which the taskfile settings should be
+ *         written.
+ *
+ * According to the ACPI spec this should be called after _STM
+ * has been evaluated for the interface. Some ACPI vendors interpret
+ * that as a hard requirement and modify the taskfile according
+ * to the Identify Drive information passed down with _STM.
+ * So one should really make sure to call this only after _STM has
+ * been executed.
+ */
+int ide_acpi_exec_tfs(ide_drive_t *drive)
+{
+	int		ret;
+	unsigned int	gtf_length;
+	unsigned long	gtf_address;
+	unsigned long	obj_loc;
+
+	DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
+
+	ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
+	if (ret < 0) {
+		DEBPRINT("get_GTF error (%d)\n", ret);
+		return ret;
+	}
+
+	DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
+
+	ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
+	kfree((void *)obj_loc);
+	if (ret < 0) {
+		DEBPRINT("set_taskfiles error (%d)\n", ret);
+	}
+
+	DEBPRINT("ret=%d\n", ret);
+
+	return ret;
+}
+
+/**
+ * ide_acpi_get_timing - get the channel (controller) timings
+ * @hwif: target IDE interface (channel)
+ *
+ * This function executes the _GTM ACPI method for the target channel.
+ *
+ */
+void ide_acpi_get_timing(ide_hwif_t *hwif)
+{
+	acpi_status		status;
+	struct acpi_buffer	output;
+	union acpi_object 	*out_obj;
+
+	/* Setting up output buffer for _GTM */
+	output.length = ACPI_ALLOCATE_BUFFER;
+	output.pointer = NULL;	/* ACPI-CA sets this; save/free it later */
+
+	/* _GTM has no input parameters */
+	status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
+				      NULL, &output);
+
+	DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
+		 status, output.pointer,
+		 (unsigned long long)output.length);
+
+	if (ACPI_FAILURE(status)) {
+		DEBPRINT("Run _GTM error: status = 0x%x\n", status);
+		return;
+	}
+
+	if (!output.length || !output.pointer) {
+		DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
+		       (unsigned long long)output.length,
+		       output.pointer);
+		kfree(output.pointer);
+		return;
+	}
+
+	out_obj = output.pointer;
+	if (out_obj->type != ACPI_TYPE_BUFFER) {
+		DEBPRINT("Run _GTM: error: "
+		       "expected object type of ACPI_TYPE_BUFFER, "
+		       "got 0x%x\n", out_obj->type);
+		kfree(output.pointer);
+		return;
+	}
+
+	if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
+	    out_obj->buffer.length != sizeof(struct GTM_buffer)) {
+		printk(KERN_ERR
+			"%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
+			"addr (0x%p)\n",
+			__func__, out_obj->buffer.length,
+			sizeof(struct GTM_buffer), out_obj->buffer.pointer);
+		kfree(output.pointer);
+		return;
+	}
+
+	memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
+	       sizeof(struct GTM_buffer));
+
+	DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%zx\n",
+		 out_obj->buffer.pointer, out_obj->buffer.length,
+		 sizeof(struct GTM_buffer));
+
+	DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
+		 hwif->acpidata->gtm.PIO_speed0,
+		 hwif->acpidata->gtm.DMA_speed0,
+		 hwif->acpidata->gtm.PIO_speed1,
+		 hwif->acpidata->gtm.DMA_speed1,
+		 hwif->acpidata->gtm.GTM_flags);
+
+	kfree(output.pointer);
+}
+
+/**
+ * ide_acpi_push_timing - set the channel (controller) timings
+ * @hwif: target IDE interface (channel)
+ *
+ * This function executes the _STM ACPI method for the target channel.
+ *
+ * _STM requires Identify Drive data, which has to passed as an argument.
+ * Unfortunately drive->id is a mangled version which we can't readily
+ * use; hence we'll get the information afresh.
+ */
+void ide_acpi_push_timing(ide_hwif_t *hwif)
+{
+	acpi_status		status;
+	struct acpi_object_list	input;
+	union acpi_object 	in_params[3];
+	struct ide_acpi_drive_link	*master = &hwif->acpidata->master;
+	struct ide_acpi_drive_link	*slave = &hwif->acpidata->slave;
+
+	/* Give the GTM buffer + drive Identify data to the channel via the
+	 * _STM method: */
+	/* setup input parameters buffer for _STM */
+	input.count = 3;
+	input.pointer = in_params;
+	in_params[0].type = ACPI_TYPE_BUFFER;
+	in_params[0].buffer.length = sizeof(struct GTM_buffer);
+	in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
+	in_params[1].type = ACPI_TYPE_BUFFER;
+	in_params[1].buffer.length = ATA_ID_WORDS * 2;
+	in_params[1].buffer.pointer = (u8 *)&master->idbuff;
+	in_params[2].type = ACPI_TYPE_BUFFER;
+	in_params[2].buffer.length = ATA_ID_WORDS * 2;
+	in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
+	/* Output buffer: _STM has no output */
+
+	status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
+				      &input, NULL);
+
+	if (ACPI_FAILURE(status)) {
+		DEBPRINT("Run _STM error: status = 0x%x\n", status);
+	}
+	DEBPRINT("_STM status: %d\n", status);
+}
+
+/**
+ * ide_acpi_set_state - set the channel power state
+ * @hwif: target IDE interface
+ * @on: state, on/off
+ *
+ * This function executes the _PS0/_PS3 ACPI method to set the power state.
+ * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
+ */
+void ide_acpi_set_state(ide_hwif_t *hwif, int on)
+{
+	ide_drive_t *drive;
+	int i;
+
+	if (ide_noacpi_psx)
+		return;
+
+	DEBPRINT("ENTER:\n");
+
+	/* channel first and then drives for power on and verse versa for power off */
+	if (on)
+		acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
+
+	ide_port_for_each_present_dev(i, drive, hwif) {
+		if (drive->acpidata->obj_handle)
+			acpi_bus_set_power(drive->acpidata->obj_handle,
+				on ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
+	}
+
+	if (!on)
+		acpi_bus_set_power(hwif->acpidata->obj_handle,
+				   ACPI_STATE_D3_COLD);
+}
+
+/**
+ * ide_acpi_init_port - initialize the ACPI link for an IDE interface
+ * @hwif: target IDE interface (channel)
+ *
+ * The ACPI spec is not quite clear when the drive identify buffer
+ * should be obtained. Calling IDENTIFY DEVICE during shutdown
+ * is not the best of ideas as the drive might already being put to
+ * sleep. And obviously we can't call it during resume.
+ * So we get the information during startup; but this means that
+ * any changes during run-time will be lost after resume.
+ */
+void ide_acpi_init_port(ide_hwif_t *hwif)
+{
+	hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
+	if (!hwif->acpidata)
+		return;
+
+	hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
+	if (!hwif->acpidata->obj_handle) {
+		DEBPRINT("no ACPI object for %s found\n", hwif->name);
+		kfree(hwif->acpidata);
+		hwif->acpidata = NULL;
+	}
+}
+
+void ide_acpi_port_init_devices(ide_hwif_t *hwif)
+{
+	ide_drive_t *drive;
+	int i, err;
+
+	if (hwif->acpidata == NULL)
+		return;
+
+	/*
+	 * The ACPI spec mandates that we send information
+	 * for both drives, regardless whether they are connected
+	 * or not.
+	 */
+	hwif->devices[0]->acpidata = &hwif->acpidata->master;
+	hwif->devices[1]->acpidata = &hwif->acpidata->slave;
+
+	/* get _ADR info for each device */
+	ide_port_for_each_present_dev(i, drive, hwif) {
+		acpi_handle dev_handle;
+
+		DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
+			 drive->name, hwif->channel, drive->dn & 1);
+
+		/* TBD: could also check ACPI object VALID bits */
+		dev_handle = acpi_get_child(hwif->acpidata->obj_handle,
+					    drive->dn & 1);
+
+		DEBPRINT("drive %s handle 0x%p\n", drive->name, dev_handle);
+
+		drive->acpidata->obj_handle = dev_handle;
+	}
+
+	/* send IDENTIFY for each device */
+	ide_port_for_each_present_dev(i, drive, hwif) {
+		err = taskfile_lib_get_identify(drive, drive->acpidata->idbuff);
+		if (err)
+			DEBPRINT("identify device %s failed (%d)\n",
+				 drive->name, err);
+	}
+
+	if (ide_noacpi || ide_acpionboot == 0) {
+		DEBPRINT("ACPI methods disabled on boot\n");
+		return;
+	}
+
+	/* ACPI _PS0 before _STM */
+	ide_acpi_set_state(hwif, 1);
+	/*
+	 * ACPI requires us to call _STM on startup
+	 */
+	ide_acpi_get_timing(hwif);
+	ide_acpi_push_timing(hwif);
+
+	ide_port_for_each_present_dev(i, drive, hwif) {
+		ide_acpi_exec_tfs(drive);
+	}
+}