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rar: Move the RAR driver into the right place as its now clean

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We exit staging rar! rar! rar!...

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Cox
2010-06-18 14:05:52 +01:00
committed by Matthew Garrett
parent 97ba0af097
commit c715a38bb7
9 changed files with 26 additions and 43 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
drivers/platform/x86/Kconfig
View File

@@ -539,6 +539,28 @@ config INTEL_SCU_IPC
some embedded Intel x86 platforms. This is not needed for PC-type
machines.
config RAR_REGISTER
bool "Restricted Access Region Register Driver"
depends on PCI && X86_MRST
default n
---help---
This driver allows other kernel drivers access to the
contents of the restricted access region control registers.
The restricted access region control registers
(rar_registers) are used to pass address and
locking information on restricted access regions
to other drivers that use restricted access regions.
The restricted access regions are regions of memory
on the Intel MID Platform that are not accessible to
the x86 processor, but are accessible to dedicated
processors on board peripheral devices.
The purpose of the restricted access regions is to
protect sensitive data from compromise by unauthorized
programs running on the x86 processor.
config INTEL_IPS
tristate "Intel Intelligent Power Sharing"
depends on ACPI

1
drivers/platform/x86/Makefile
View File

@@ -26,4 +26,5 @@ obj-$(CONFIG_TOPSTAR_LAPTOP) += topstar-laptop.o
obj-$(CONFIG_ACPI_TOSHIBA) += toshiba_acpi.o
obj-$(CONFIG_TOSHIBA_BT_RFKILL) += toshiba_bluetooth.o
obj-$(CONFIG_INTEL_SCU_IPC) += intel_scu_ipc.o
obj-$(CONFIG_RAR_REGISTER) += intel_rar_register.o
obj-$(CONFIG_INTEL_IPS) += intel_ips.o

671
drivers/platform/x86/intel_rar_register.c Normal file
View File

@@ -0,0 +1,671 @@
/*
* rar_register.c - An Intel Restricted Access Region register driver
*
* Copyright(c) 2009 Intel Corporation. All rights reserved.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*
* -------------------------------------------------------------------
* 20091204 Mark Allyn <mark.a.allyn@intel.com>
* Ossama Othman <ossama.othman@intel.com>
* Cleanup per feedback from Alan Cox and Arjan Van De Ven
*
* 20090806 Ossama Othman <ossama.othman@intel.com>
* Return zero high address if upper 22 bits is zero.
* Cleaned up checkpatch errors.
* Clarified that driver is dealing with bus addresses.
*
* 20090702 Ossama Othman <ossama.othman@intel.com>
* Removed unnecessary include directives
* Cleaned up spinlocks.
* Cleaned up logging.
* Improved invalid parameter checks.
* Fixed and simplified RAR address retrieval and RAR locking
* code.
*
* 20090626 Mark Allyn <mark.a.allyn@intel.com>
* Initial publish
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/rar_register.h>
/* === Lincroft Message Bus Interface === */
#define LNC_MCR_OFFSET 0xD0 /* Message Control Register */
#define LNC_MDR_OFFSET 0xD4 /* Message Data Register */
/* Message Opcodes */
#define LNC_MESSAGE_READ_OPCODE 0xD0
#define LNC_MESSAGE_WRITE_OPCODE 0xE0
/* Message Write Byte Enables */
#define LNC_MESSAGE_BYTE_WRITE_ENABLES 0xF
/* B-unit Port */
#define LNC_BUNIT_PORT 0x3
/* === Lincroft B-Unit Registers - Programmed by IA32 firmware === */
#define LNC_BRAR0L 0x10
#define LNC_BRAR0H 0x11
#define LNC_BRAR1L 0x12
#define LNC_BRAR1H 0x13
/* Reserved for SeP */
#define LNC_BRAR2L 0x14
#define LNC_BRAR2H 0x15
/* Moorestown supports three restricted access regions. */
#define MRST_NUM_RAR 3
/* RAR Bus Address Range */
struct rar_addr {
dma_addr_t low;
dma_addr_t high;
};
/*
* We create one of these for each RAR
*/
struct client {
int (*callback)(unsigned long data);
unsigned long driver_priv;
bool busy;
};
static DEFINE_MUTEX(rar_mutex);
static DEFINE_MUTEX(lnc_reg_mutex);
/*
* One per RAR device (currently only one device)
*/
struct rar_device {
struct rar_addr rar_addr[MRST_NUM_RAR];
struct pci_dev *rar_dev;
bool registered;
bool allocated;
struct client client[MRST_NUM_RAR];
};
/* Current platforms have only one rar_device for 3 rar regions */
static struct rar_device my_rar_device;
/*
* Abstract out multiple device support. Current platforms only
* have a single RAR device.
*/
/**
* alloc_rar_device - return a new RAR structure
*
* Return a new (but not yet ready) RAR device object
*/
static struct rar_device *alloc_rar_device(void)
{
if (my_rar_device.allocated)
return NULL;
my_rar_device.allocated = 1;
return &my_rar_device;
}
/**
* free_rar_device - free a RAR object
* @rar: the RAR device being freed
*
* Release a RAR object and any attached resources
*/
static void free_rar_device(struct rar_device *rar)
{
pci_dev_put(rar->rar_dev);
rar->allocated = 0;
}
/**
* _rar_to_device - return the device handling this RAR
* @rar: RAR number
* @off: returned offset
*
* Internal helper for looking up RAR devices. This and alloc are the
* two functions that need touching to go to multiple RAR devices.
*/
static struct rar_device *_rar_to_device(int rar, int *off)
{
if (rar >= 0 && rar <= 3) {
*off = rar;
return &my_rar_device;
}
return NULL;
}
/**
* rar_to_device - return the device handling this RAR
* @rar: RAR number
* @off: returned offset
*
* Return the device this RAR maps to if one is present, otherwise
* returns NULL. Reports the offset relative to the base of this
* RAR device in off.
*/
static struct rar_device *rar_to_device(int rar, int *off)
{
struct rar_device *rar_dev = _rar_to_device(rar, off);
if (rar_dev == NULL || !rar_dev->registered)
return NULL;
return rar_dev;
}
/**
* rar_to_client - return the client handling this RAR
* @rar: RAR number
*
* Return the client this RAR maps to if a mapping is known, otherwise
* returns NULL.
*/
static struct client *rar_to_client(int rar)
{
int idx;
struct rar_device *r = _rar_to_device(rar, &idx);
if (r != NULL)
return &r->client[idx];
return NULL;
}
/**
* rar_read_addr - retrieve a RAR mapping
* @pdev: PCI device for the RAR
* @offset: offset for message
* @addr: returned address
*
* Reads the address of a given RAR register. Returns 0 on success
* or an error code on failure.
*/
static int rar_read_addr(struct pci_dev *pdev, int offset, dma_addr_t *addr)
{
/*
* ======== The Lincroft Message Bus Interface ========
* Lincroft registers may be obtained via PCI from
* the host bridge using the Lincroft Message Bus
* Interface. That message bus interface is generally
* comprised of two registers: a control register (MCR, 0xDO)
* and a data register (MDR, 0xD4).
*
* The MCR (message control register) format is the following:
* 1. [31:24]: Opcode
* 2. [23:16]: Port
* 3. [15:8]: Register Offset
* 4. [7:4]: Byte Enables (use 0xF to set all of these bits
* to 1)
* 5. [3:0]: reserved
*
* Read (0xD0) and write (0xE0) opcodes are written to the
* control register when reading and writing to Lincroft
* registers, respectively.
*
* We're interested in registers found in the Lincroft
* B-unit. The B-unit port is 0x3.
*
* The six B-unit RAR register offsets we use are listed
* earlier in this file.
*
* Lastly writing to the MCR register requires the "Byte
* enables" bits to be set to 1. This may be achieved by
* writing 0xF at bit 4.
*
* The MDR (message data register) format is the following:
* 1. [31:0]: Read/Write Data
*
* Data being read from this register is only available after
* writing the appropriate control message to the MCR
* register.
*
* Data being written to this register must be written before
* writing the appropriate control message to the MCR
* register.
*/
int result;
u32 addr32;
/* Construct control message */
u32 const message =
(LNC_MESSAGE_READ_OPCODE << 24)
| (LNC_BUNIT_PORT << 16)
| (offset << 8)
| (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
dev_dbg(&pdev->dev, "Offset for 'get' LNC MSG is %x\n", offset);
/*
* We synchronize access to the Lincroft MCR and MDR registers
* until BOTH the command is issued through the MCR register
* and the corresponding data is read from the MDR register.
* Otherwise a race condition would exist between accesses to
* both registers.
*/
mutex_lock(&lnc_reg_mutex);
/* Send the control message */
result = pci_write_config_dword(pdev, LNC_MCR_OFFSET, message);
if (!result) {
/* Read back the address as a 32bit value */
result = pci_read_config_dword(pdev, LNC_MDR_OFFSET, &addr32);
*addr = (dma_addr_t)addr32;
}
mutex_unlock(&lnc_reg_mutex);
return result;
}
/**
* rar_set_addr - Set a RAR mapping
* @pdev: PCI device for the RAR
* @offset: offset for message
* @addr: address to set
*
* Sets the address of a given RAR register. Returns 0 on success
* or an error code on failure.
*/
static int rar_set_addr(struct pci_dev *pdev,
int offset,
dma_addr_t addr)
{
/*
* Data being written to this register must be written before
* writing the appropriate control message to the MCR
* register.
* See rar_get_addrs() for a description of the
* message bus interface being used here.
*/
int result;
/* Construct control message */
u32 const message = (LNC_MESSAGE_WRITE_OPCODE << 24)
| (LNC_BUNIT_PORT << 16)
| (offset << 8)
| (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
/*
* We synchronize access to the Lincroft MCR and MDR registers
* until BOTH the command is issued through the MCR register
* and the corresponding data is read from the MDR register.
* Otherwise a race condition would exist between accesses to
* both registers.
*/
mutex_lock(&lnc_reg_mutex);
/* Send the control message */
result = pci_write_config_dword(pdev, LNC_MDR_OFFSET, addr);
if (!result)
/* And address */
result = pci_write_config_dword(pdev, LNC_MCR_OFFSET, message);
mutex_unlock(&lnc_reg_mutex);
return result;
}
/*
* rar_init_params - Initialize RAR parameters
* @rar: RAR device to initialise
*
* Initialize RAR parameters, such as bus addresses, etc. Returns 0
* on success, or an error code on failure.
*/
static int init_rar_params(struct rar_device *rar)
{
struct pci_dev *pdev = rar->rar_dev;
unsigned int i;
int result = 0;
int offset = 0x10; /* RAR 0 to 2 in order low/high/low/high/... */
/* Retrieve RAR start and end bus addresses.
* Access the RAR registers through the Lincroft Message Bus
* Interface on PCI device: 00:00.0 Host bridge.
*/
for (i = 0; i < MRST_NUM_RAR; ++i) {
struct rar_addr *addr = &rar->rar_addr[i];
result = rar_read_addr(pdev, offset++, &addr->low);
if (result != 0)
return result;
result = rar_read_addr(pdev, offset++, &addr->high);
if (result != 0)
return result;
/*
* Only the upper 22 bits of the RAR addresses are
* stored in their corresponding RAR registers so we
* must set the lower 10 bits accordingly.
* The low address has its lower 10 bits cleared, and
* the high address has all its lower 10 bits set,
* e.g.:
* low = 0x2ffffc00
*/
addr->low &= (dma_addr_t)0xfffffc00u;
/*
* Set bits 9:0 on uppser address if bits 31:10 are non
* zero; otherwize clear all bits
*/
if ((addr->high & 0xfffffc00u) == 0)
addr->high = 0;
else
addr->high |= 0x3ffu;
}
/* Done accessing the device. */
if (result == 0) {
for (i = 0; i != MRST_NUM_RAR; ++i) {
/*
* "BRAR" refers to the RAR registers in the
* Lincroft B-unit.
*/
dev_info(&pdev->dev, "BRAR[%u] bus address range = "
"[%lx, %lx]\n", i,
(unsigned long)rar->rar_addr[i].low,
(unsigned long)rar->rar_addr[i].high);
}
}
return result;
}
/**
* rar_get_address - get the bus address in a RAR
* @start: return value of start address of block
* @end: return value of end address of block
*
* The rar_get_address function is used by other device drivers
* to obtain RAR address information on a RAR. It takes three
* parameters:
*
* The function returns a 0 upon success or an error if there is no RAR
* facility on this system.
*/
int rar_get_address(int rar_index, dma_addr_t *start, dma_addr_t *end)
{
int idx;
struct rar_device *rar = rar_to_device(rar_index, &idx);
if (rar == NULL) {
WARN_ON(1);
return -ENODEV;
}
*start = rar->rar_addr[idx].low;
*end = rar->rar_addr[idx].high;
return 0;
}
EXPORT_SYMBOL(rar_get_address);
/**
* rar_lock - lock a RAR register
* @rar_index: RAR to lock (0-2)
*
* The rar_lock function is ued by other device drivers to lock an RAR.
* once a RAR is locked, it stays locked until the next system reboot.
*
* The function returns a 0 upon success or an error if there is no RAR
* facility on this system, or the locking fails
*/
int rar_lock(int rar_index)
{
struct rar_device *rar;
int result;
int idx;
dma_addr_t low, high;
rar = rar_to_device(rar_index, &idx);
if (rar == NULL) {
WARN_ON(1);
return -EINVAL;
}
low = rar->rar_addr[idx].low & 0xfffffc00u;
high = rar->rar_addr[idx].high & 0xfffffc00u;
/*
* Only allow I/O from the graphics and Langwell;
* not from the x86 processor
*/
if (rar_index == RAR_TYPE_VIDEO) {
low |= 0x00000009;
high |= 0x00000015;
} else if (rar_index == RAR_TYPE_AUDIO) {
/* Only allow I/O from Langwell; nothing from x86 */
low |= 0x00000008;
high |= 0x00000018;
} else
/* Read-only from all agents */
high |= 0x00000018;
/*
* Now program the register using the Lincroft message
* bus interface.
*/
result = rar_set_addr(rar->rar_dev,
2 * idx, low);
if (result == 0)
result = rar_set_addr(rar->rar_dev,
2 * idx + 1, high);
return result;
}
EXPORT_SYMBOL(rar_lock);
/**
* register_rar - register a RAR handler
* @num: RAR we wish to register for
* @callback: function to call when RAR support is available
* @data: data to pass to this function
*
* The register_rar function is to used by other device drivers
* to ensure that this driver is ready. As we cannot be sure of
* the compile/execute order of drivers in ther kernel, it is
* best to give this driver a callback function to call when
* it is ready to give out addresses. The callback function
* would have those steps that continue the initialization of
* a driver that do require a valid RAR address. One of those
* steps would be to call rar_get_address()
*
* This function return 0 on success or an error code on failure.
*/
int register_rar(int num, int (*callback)(unsigned long data),
unsigned long data)
{
/* For now we hardcode a single RAR device */
struct rar_device *rar;
struct client *c;
int idx;
int retval = 0;
mutex_lock(&rar_mutex);
/* Do we have a client mapping for this RAR number ? */
c = rar_to_client(num);
if (c == NULL) {
retval = -ERANGE;
goto done;
}
/* Is it claimed ? */
if (c->busy) {
retval = -EBUSY;
goto done;
}
c->busy = 1;
/* See if we have a handler for this RAR yet, if we do then fire it */
rar = rar_to_device(num, &idx);
if (rar) {
/*
* if the driver already registered, then we can simply
* call the callback right now
*/
(*callback)(data);
goto done;
}
/* Arrange to be called back when the hardware is found */
c->callback = callback;
c->driver_priv = data;
done:
mutex_unlock(&rar_mutex);
return retval;
}
EXPORT_SYMBOL(register_rar);
/**
* unregister_rar - release a RAR allocation
* @num: RAR number
*
* Releases a RAR allocation, or pending allocation. If a callback is
* pending then this function will either complete before the unregister
* returns or not at all.
*/
void unregister_rar(int num)
{
struct client *c;
mutex_lock(&rar_mutex);
c = rar_to_client(num);
if (c == NULL || !c->busy)
WARN_ON(1);
else
c->busy = 0;
mutex_unlock(&rar_mutex);
}
EXPORT_SYMBOL(unregister_rar);
/**
* rar_callback - Process callbacks
* @rar: new RAR device
*
* Process the callbacks for a newly found RAR device.
*/
static void rar_callback(struct rar_device *rar)
{
struct client *c = &rar->client[0];
int i;
mutex_lock(&rar_mutex);
rar->registered = 1; /* Ensure no more callbacks queue */
for (i = 0; i < MRST_NUM_RAR; i++) {
if (c->callback && c->busy) {
c->callback(c->driver_priv);
c->callback = NULL;
}
c++;
}
mutex_unlock(&rar_mutex);
}
/**
* rar_probe - PCI probe callback
* @dev: PCI device
* @id: matching entry in the match table
*
* A RAR device has been discovered. Initialise it and if successful
* process any pending callbacks that can now be completed.
*/
static int rar_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
int error;
struct rar_device *rar;
dev_dbg(&dev->dev, "PCI probe starting\n");
rar = alloc_rar_device();
if (rar == NULL)
return -EBUSY;
/* Enable the device */
error = pci_enable_device(dev);
if (error) {
dev_err(&dev->dev,
"Error enabling RAR register PCI device\n");
goto end_function;
}
/* Fill in the rar_device structure */
rar->rar_dev = pci_dev_get(dev);
pci_set_drvdata(dev, rar);
/*
* Initialize the RAR parameters, which have to be retrieved
* via the message bus interface.
*/
error = init_rar_params(rar);
if (error) {
pci_disable_device(dev);
dev_err(&dev->dev, "Error retrieving RAR addresses\n");
goto end_function;
}
/* now call anyone who has registered (using callbacks) */
rar_callback(rar);
return 0;
end_function:
free_rar_device(rar);
return error;
}
const struct pci_device_id rar_pci_id_tbl[] = {
{ PCI_VDEVICE(INTEL, 0x4110) },
{ 0 }
};
MODULE_DEVICE_TABLE(pci, rar_pci_id_tbl);
const struct pci_device_id *my_id_table = rar_pci_id_tbl;
/* field for registering driver to PCI device */
static struct pci_driver rar_pci_driver = {
.name = "rar_register_driver",
.id_table = rar_pci_id_tbl,
.probe = rar_probe,
/* Cannot be unplugged - no remove */
};
static int __init rar_init_handler(void)
{
return pci_register_driver(&rar_pci_driver);
}
static void __exit rar_exit_handler(void)
{
pci_unregister_driver(&rar_pci_driver);
}
module_init(rar_init_handler);
module_exit(rar_exit_handler);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Intel Restricted Access Region Register Driver");