Re: [PATCH] PCI/ACPI: move _OSC code to pci_root.c

[Andrew Patterson <andrew.patterson@hp.com>]

On Tue, 2009-02-03 at 14:57 +0900, Kenji Kaneshige wrote:
> Move PCI _OSC management code from drivers/pci/pci-acpi.c to
> drivers/acpi/pci_root.c. The benefits are
> 
> - We no longer need struct osc_data and its management code (contents
>   are moved to struct acpi_pci_root). This simplify the code, and we
>   no longer care about kmalloc() failure.
> 
> - We can make pci_acpi_osc_support() be a static function, which is
>   called only from drivers/acpi/pci_root.c.
> 
> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
> 
> ---
>  drivers/acpi/pci_root.c  |  178 ++++++++++++++++++++++++++++++++++++++
>  drivers/pci/pci-acpi.c   |  215 -----------------------------------------------
>  include/linux/pci-acpi.h |    1 
>  3 files changed, 176 insertions(+), 218 deletions(-)
> 
> Index: 20090130/drivers/acpi/pci_root.c
> ===================================================================
> --- 20090130.orig/drivers/acpi/pci_root.c
> +++ 20090130/drivers/acpi/pci_root.c
> @@ -66,11 +66,18 @@ struct acpi_pci_root {
>  	struct acpi_device * device;
>  	struct acpi_pci_id id;
>  	struct pci_bus *bus;
> +
> +	u32 osc_support_set;	/* _OSC state of support bits */
> +	u32 osc_control_set;	/* _OSC state of control bits */
> +	u32 osc_control_qry;	/* the latest _OSC query result */
> +
> +	u32 osc_queried:1;	/* has _OSC control been queried? */
>  };
>  
>  static LIST_HEAD(acpi_pci_roots);
>  
>  static struct acpi_pci_driver *sub_driver;
> +static DEFINE_MUTEX(osc_lock);
>  
>  int acpi_pci_register_driver(struct acpi_pci_driver *driver)
>  {
> @@ -185,6 +192,173 @@ static void acpi_pci_bridge_scan(struct 
>  		}
>  }
>  
> +static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
> +			  0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
> +
> +static acpi_status acpi_pci_run_osc(acpi_handle handle,
> +				    const u32 *capbuf, u32 *retval)
> +{
> +	acpi_status status;
> +	struct acpi_object_list input;
> +	union acpi_object in_params[4];
> +	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
> +	union acpi_object *out_obj;
> +	u32 errors;
> +
> +	/* Setting up input parameters */
> +	input.count = 4;
> +	input.pointer = in_params;
> +	in_params[0].type 		= ACPI_TYPE_BUFFER;
> +	in_params[0].buffer.length 	= 16;
> +	in_params[0].buffer.pointer	= OSC_UUID;
> +	in_params[1].type 		= ACPI_TYPE_INTEGER;
> +	in_params[1].integer.value 	= 1;
> +	in_params[2].type 		= ACPI_TYPE_INTEGER;
> +	in_params[2].integer.value	= 3;
> +	in_params[3].type		= ACPI_TYPE_BUFFER;
> +	in_params[3].buffer.length 	= 12;
> +	in_params[3].buffer.pointer 	= (u8 *)capbuf;
> +
> +	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
> +	if (ACPI_FAILURE(status))
> +		return status;
> +
> +	if (!output.length)
> +		return AE_NULL_OBJECT;
> +
> +	out_obj = output.pointer;
> +	if (out_obj->type != ACPI_TYPE_BUFFER) {
> +		printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
> +		status = AE_TYPE;
> +		goto out_kfree;
> +	}
> +	/* Need to ignore the bit0 in result code */
> +	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
> +	if (errors) {
> +		if (errors & OSC_REQUEST_ERROR)
> +			printk(KERN_DEBUG "_OSC request fails\n");
> +		if (errors & OSC_INVALID_UUID_ERROR)
> +			printk(KERN_DEBUG "_OSC invalid UUID\n");
> +		if (errors & OSC_INVALID_REVISION_ERROR)
> +			printk(KERN_DEBUG "_OSC invalid revision\n");
> +		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
> +			if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
> +				goto out_success;
> +			printk(KERN_DEBUG "_OSC FW not grant req. control\n");

Can this be worded better? Perhaps "Firmware would not grant requested
_OSC control"? I know this is not your code, but maybe we can fix this
now.

> +			status = AE_SUPPORT;
> +			goto out_kfree;
> +		}
> +		status = AE_ERROR;
> +		goto out_kfree;
> +	}
> +out_success:
> +	*retval = *((u32 *)(out_obj->buffer.pointer + 8));
> +	status = AE_OK;
> +
> +out_kfree:
> +	kfree(output.pointer);
> +	return status;
> +}
> +
> +static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
> +{
> +	acpi_status status;
> +	u32 support_set, result, capbuf[3];
> +
> +	/* do _OSC query for all possible controls */
> +	support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
> +	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
> +	capbuf[OSC_SUPPORT_TYPE] = support_set;
> +	capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
> +
> +	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
> +	if (ACPI_SUCCESS(status)) {
> +		root->osc_support_set = support_set;
> +		root->osc_control_qry = result;
> +		root->osc_queried = 1;
> +	}
> +	return status;
> +}
> +
> +static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
> +{
> +	acpi_status status;
> +	acpi_handle tmp;
> +
> +	status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
> +	if (ACPI_FAILURE(status))
> +		return status;
> +	mutex_lock(&osc_lock);
> +	status = acpi_pci_query_osc(root, flags);
> +	mutex_unlock(&osc_lock);
> +	return status;
> +}
> +
> +static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
> +{
> +	struct acpi_pci_root *root;
> +	list_for_each_entry(root, &acpi_pci_roots, node) {
> +		if (root->device->handle == handle)
> +			return root;
> +	}
> +	return NULL;
> +}
> +
> +/**
> + * pci_osc_control_set - commit requested control to Firmware

Should this function be renamed to acpi_pci_osc_control_set?

> + * @handle: acpi_handle for the target ACPI object
> + * @flags: driver's requested control bits
> + *
> + * Attempt to take control from Firmware on requested control bits.
> + **/
> +acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
> +{

> +	acpi_status status;
> +	u32 control_req, result, capbuf[3];
> +	acpi_handle tmp;
> +	struct acpi_pci_root *root;
> +
> +	status = acpi_get_handle(handle, "_OSC", &tmp);
> +	if (ACPI_FAILURE(status))
> +		return status;
> +
> +	control_req = (flag

> s & OSC_CONTROL_MASKS);
> +	if (!control_req)
> +		return AE_TYPE;
> +
> +	root = acpi_pci_find_root(handle);
> +	if (!root)
> +		return AE_NOT_EXIST;
> +
> +	mutex_lock(&osc_lock);
> +	/* No need to evaluate _OSC if the control was already granted. */
> +	if ((root->osc_control_set & control_req) == control_req)
> +		goto out;
> +
> +	/* Need to query controls first before requesting them */
> +	if (!root->osc_queried) {
> +		status = acpi_pci_query_osc(root, root->osc_support_set);
> +		if (ACPI_FAILURE(status))
> +			goto out;
> +	}
> +	if ((root->osc_control_qry & control_req) != control_req) {
> +		printk(KERN

> _DEBUG "_OSC FW not grant req. control\n");

See above.

> +		status = AE_SUPPORT;
> +		goto out;
> +	}
> +
> +	capbuf[OSC_QUERY_TYPE] = 0;
> +	capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
> +	capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
> +	status = acpi_pci_run_osc(handle, capbuf, &result);
> +	if (ACPI_SUCCESS(status))
> +		root->osc_control_set = result;
> +out:
> +	mutex_unlock(&osc_lock);
> +	return status;
> +}
> +EXPORT_SYMBOL(pci_osc_control_set);
> +
>  static int __devinit acpi_pci_root_add(struct acpi_device *device)
>  {
>  	int result = 0;
> @@ -217,7 +391,7 @@ static int __devinit acpi_pci_root_add(s
>  	 * PCI domains, so we indicate this in _OSC support capabilities.
>  	 */
>  	flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
> -	pci_acpi_osc_support(device->handle, flags);
> +	acpi_pci_osc_support(root, flags);
>  
>  	/* 
>  	 * Segment
> @@ -353,7 +527,7 @@ static int __devinit acpi_pci_root_add(s
>  	if (pci_msi_enabled())
>  		flags |= OS

> C_MSI_SUPPORT;
>  	if (flags != base_flags)
> -		pci_acpi_osc_support(device->handle, flags);
> +		acpi_pci_osc_support(root, flags);
>  
>        end:
>  	if (result) {
> Index: 20090130/drivers/pci/pci-acpi.c
> ===================================================================
> --- 20090130.orig/drivers/pci/pci-acpi.c
> +++ 20090130/drivers/pci/pci-acpi.c
> @@ -18,221 +18,6 @@
>  #include <linux/pci-acpi.h>
>  #include "pci.h"
>  
> -struct acpi_osc_data {
> -	acpi_handle handle;
> -	u32 support_set;
> -	u32 control_set;
> -	u32 control_query;
> -	int is_queried;
> -	struct list_head sibiling;
> -};
> -static LIST_HEAD(acpi_osc_data_list);
> -
> -struct acpi_osc_args {
> -	u32 capbuf[3];
> -};
> -
> -static DEFINE_MUTEX(pci_acpi_lock);
> -
> -static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
> -{
> -	struct acpi_osc_data *data;
> -
> -	list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
> -		if (data->handle == handle)
> -			return data;
> -	}
> -	data = kzalloc(sizeof(*data), GFP_KERNEL);
> -	if (!data)
> -		return NULL;
> -	INIT_LIST_HEAD(&data->sibiling);
> -	data->handle = handle;
> -	list_add_tail(&data->sibiling, &acpi_osc_data_list);
> -	return data;
> -}
> -
> -static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
> -			  0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
> -
> -static acpi_status acpi_run_osc(acpi_handle handle,
> -				struct acpi_osc_args *osc_args, u32 *retval)
> -{
> -	acpi_status status;
> -	struct acpi_object_list input;
> -	union acpi_object in_params[4];
> -	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
> -	union acpi_object *out_obj;
> -	u32 errors, flags = osc_args->capbuf[OSC_QUERY_TYPE];
> -
> -	/* Setting up input parameters */
> -	input.count = 4;
> -	input.pointer = in_params;
> -	in_params[0].type 		= ACPI_TYPE_BUFFER;
> -	in_params[0].buffer.length 	= 16;
> -	in_params[0].buffer.pointer	= OSC_UUID;
> -	in_params[1].type 		= ACPI_TYPE_INTEGER;
> -	in_params[1].integer.value 	= 1;
> -	in_params[2].type 		= ACPI_TYPE_INTEGER;
> -	in_params[2].integer.value	= 3;
> -	in_params[3].type		= ACPI_TYPE_BUFFER;
> -	in_params[3].buffer.length 	= 12;
> -	in_params[3].buffer.pointer 	= (u8 *)osc_args->capbuf;
> -
> -	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
> -	if (ACPI_FAILURE(status))
> -		return status;
> -
> -	if (!output.length)
> -		return AE_NULL_OBJECT;
> -
> -	out_obj = output.pointer;
> -	if (out_obj->type != ACPI_TYPE_BUFFER) {
> -		printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
> -		status = AE_TYPE;
> -		goto out_kfree;
> -	}
> -	/* Need to ignore the bit0 in result code */
> -	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
> -	if (errors) {
> -		if (errors & OSC_REQUEST_ERROR)
> -			printk(KERN_DEBUG "_OSC request fails\n"); 
> -		if (errors & OSC_INVALID_UUID_ERROR)
> -			printk(KERN_DEBUG "_OSC invalid UUID\n"); 
> -		if (errors & OSC_INVALID_REVISION_ERROR)
> -			printk(KERN_DEBUG "_OSC invalid revision\n"); 
> -		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
> -			if (flags & OSC_QUERY_ENABLE)
> -				goto out_success;
> -			printk(KERN_DEBUG "_OSC FW not grant req. control\n");
> -			status = AE_SUPPORT;
> -			goto out_kfree;
> -		}
> -		status = AE_ERROR;
> -		goto out_kfree;
> -	}
> -out_success:
> -	*retval = *((u32 *)(out_obj->buffer.pointer + 8));
> -	status = AE_OK;
> -
> -out_kfree:
> -	kfree(output.pointer);
> -	return status;
> -}
> -
> -static acpi_status __acpi_

> query_osc(u32 flags, struct acpi_osc_data *osc_data)
> -{
> -	acpi_status status;
> -	u32 support_set, result;
> -	struct acpi_osc_args osc_args;
> -
> -	/* do _OSC query for all possible controls */
> -	support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
> -	osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
> -	osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
> -	osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
> -
> -	status = acpi_run_osc(osc_data->handle, &osc_args, &result);
> -	if (ACPI_SUCCESS(status)) {
> -		osc_data->support_set = support_set;
> -		osc_data->control_query = result;
> -		osc_data->is_queried = 1;
> -	}
> -
> -	return status;
> -}
> -
> -/*
> - * pci_acpi_osc_support: Invoke _OSC indicating support for the given feature
> - * @flags: Bitmask of flags to support
> - *
> - * See the ACPI spec for the definition of the flags
> - */
> -int pci_acpi_osc_support(acpi_handle handle, u32 flags)
> -{
> -	acpi_status status;
> -	acpi_handle tmp;
> -	struct acpi_osc_data *osc_data;
> -	int rc = 0;
> -
> -	status = acpi_get_handle(handle, "_OSC", &tmp);
> -	if (ACPI_FAILURE(status))
> -		return -ENOTTY;
> -
> -	mutex_lock(&pci_acpi_lock);
> -	osc_data = acpi_get_osc_data(handle);
> -	if (!osc_data) {
> -		printk(KERN_ERR "acpi osc data array is full\n");
> -		rc = -ENOMEM;
> -		goto out;
> -	}
> -
> -	__acpi_query_osc(flags, osc_data);
> -out:
> -	mutex_unlock(&pci_acpi_lock);
> -	return rc;
> -}
> -
> -/**
> - * pci_osc_control_set - commit requested control to Firmware
> - * @handle: acpi_handle for the target ACPI object
> - * @flags: driver's requested control bits
> - *
> - * Attempt to take control from Firmware on requested control bits.
> - **/
> -acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
> -{
> -	acpi_status status;
> -	u32 control_req, control_set, result;
> -	acpi_handle tmp;
> -	struct acpi_osc_data *osc_data;
> -	struct acpi_osc_args osc_args;
> -
> -	status = acpi_get_handle(handle, "_OSC", &tmp);
> -	if (ACPI_FAILURE(status))
> -		return status;
> -
> -	mutex_lock(&pci_acpi_lock);
> -	osc_data = acpi_get_osc_data(handle);
> -	if (!osc_data) {
> -		printk(KERN_ERR "acpi osc data array is full\n");
> -		status = AE_ERROR;
> -		goto out;
> -	}
> -
> -	control_req = (flags & OSC_CONTROL_MASKS);
> -	if (!control_req) {
> -		status = AE_TYPE;
> -		goto out;
> -	}
> -
> -	/* No need to evaluate _OSC if the control was already granted. */
> -	if ((osc_data->control_set & control_req) == control_req)
> -		goto out;
> -
> -	if (!osc_data->is_queried) {
> -		status = __acpi_query_osc(osc_data->support_set, osc_data);
> -		if (ACPI_FAILURE(status))
> -			goto out;
> -	}
> -
> -	if ((osc_data->control_query & control_req) != control_req) {
> -		status = AE_SUPPORT;
> -		goto out;
> -	}
> -
> -	control_set = osc_data->control_set | control_req;
> -	osc_args.capbuf[OSC_QUERY_TYPE] = 0;
> -	osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
> -	osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
> -	status = acpi_run_osc(handle, &osc_args, &result);
> -	if (ACPI_SUCCESS(status))
> -		osc_data->control_set = result;
> -out:
> -	mutex_unlock(&pci_acpi_lock);
> -	return status;
> -}
> -EXPORT_SYMBOL(pci_osc_control_set);
> -
>  /*
>   * _SxD returns the D-state with the highest power
>   * (lowest D-state number) supported in the S-state "x".
> Index: 20090130/include/linux/pci-acpi.h
> ===================================================================
> --- 20090130.orig/include/linux/pci-acpi.h
> +++ 20090130/include/linux/pci-acpi.h
> @@ -50,7 +50,6 @@
>  
>  #ifdef CONFIG_ACPI
>  extern acpi_status pci_osc_control_set(acpi_handle handle, u32 flags);
> -int pci_acpi_osc_support(acpi_handle handle, u32 flags);
>  static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
>  {
>  	/* Find root host bridge */

-- 
Andrew Patterson
Hewlett-Packard Company