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Date: Mon, 18 Jan 2010 13:23:41 -0800
From: Mark Allyn <mark.a.allyn@...el.com>
To: linux-kernel@...r.kernel.org, greg@...ah.com, alan@...ux.intel.com,
charles.f.johnson@...el.com
Cc: Mark Allyn <mark.a.allyn@...el.com>
Subject: [PATCH] Update rar_register.c to remove checkpatch errors and debug
The purpose of this patch is to clean up the rar_register
driver itself so that it uses proper data types; clean up
checkpatch issues; and to get the driver working.
This is the seventh of seven patches for the rar_register driver
for Sunday, January 17, 2009
The rar stands for restricted access region. The restricted access
region is an area of memory that can be locked from access by the
x86 processor.
The purpose of the restricted access region is to safeguard confidential
information from any unauthorized software running on the x86 processor.
The purpose of this driver is to enable other drivers to obtain
the address ranges of the restricted regions as well as lock them.
This patch is referenced off the linux-next repository as pulled
on Sunday, January 17, 2010
Signed-off-by: Mark Allyn <mark.a.allyn@...el.com>
Date: January 17, 2010
---
drivers/staging/rar_register/rar_register.c | 746 ++++++++++++++++----------
1 files changed, 459 insertions(+), 287 deletions(-)
diff --git a/drivers/staging/rar_register/rar_register.c b/drivers/staging/rar_register/rar_register.c
index 4b9a3a3..79c4c65 100644
--- a/drivers/staging/rar_register/rar_register.c
+++ b/drivers/staging/rar_register/rar_register.c
@@ -1,34 +1,68 @@
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/cdev.h>
-#include <linux/kdev_t.h>
-#include <linux/semaphore.h>
-#include <linux/mm.h>
-#include <linux/poll.h>
-#include <linux/wait.h>
-#include <linux/ioctl.h>
-#include <linux/ioport.h>
-#include <linux/io.h>
-#include <linux/interrupt.h>
-#include <linux/pagemap.h>
-#include <linux/pci.h>
-#include <linux/firmware.h>
-#include <linux/sched.h>
+/*
+ * rar_register.c - An Intel Restricted Access Region register driver
+ *
+ * Copyright(c) 2010 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@...el.com>
+ * Ossama Othman <ossama.othman@...el.com>
+ * Cleanup per feedback from Alan Cox and Arjan Van De Ven
+ *
+ * 20090806 Ossama Othman <ossama.othman@...el.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@...el.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@...el.com>
+ * Initial publish
+ */
+
+#define DEBUG 1
+
#include <linux/rar/rar_register.h>
#include <linux/rar/memrar.h>
-/* The following defines are for the IPC process to retrieve RAR in */
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
/* === Lincroft Message Bus Interface === */
/* Message Control Register */
#define LNC_MCR_OFFSET 0xD0
+/* Maximum number of clients (other drivers using this driver) */
+#define MAX_RAR_CLIENTS 10
+
/* Message Data Register */
#define LNC_MDR_OFFSET 0xD4
/* Message Opcodes */
-#define LNC_MESSAGE_READ_OPCODE 0xD0
+#define LNC_MESSAGE_READ_OPCODE 0xD0
#define LNC_MESSAGE_WRITE_OPCODE 0xE0
/* Message Write Byte Enables */
@@ -38,58 +72,73 @@
#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
+#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
+#define LNC_BRAR2L 0x14
+#define LNC_BRAR2H 0x15
+
+/* Moorestown supports three restricted access regions. */
+#define MRST_NUM_RAR 3
-/* This structure is only used during module initialization. */
-struct RAR_offsets {
- int low; /* Register offset for low RAR physical address. */
- int high; /* Register offset for high RAR physical address. */
+/* RAR Bus Address Range */
+struct RAR_address_range {
+ dma_addr_t low;
+ dma_addr_t high;
};
-struct pci_dev *rar_dev;
-static uint32_t registered;
-
-/* Moorestown supports three restricted access regions. */
-#define MRST_NUM_RAR 3
+/* Structure containing low and high RAR register offsets. */
+struct RAR_offsets {
+ u32 low; /* Register offset for low RAR bus address. */
+ u32 high; /* Register offset for high RAR bus address. */
+};
-struct RAR_address_struct rar_addr[MRST_NUM_RAR];
+struct client {
+ int (*client_callback)(void *client_data);
+ void *customer_data;
+ int client_called;
+ };
-/* prototype for init */
-static int __init rar_init_handler(void);
-static void __exit rar_exit_handler(void);
+static DEFINE_MUTEX(rar_mutex);
+static DEFINE_MUTEX(lnc_reg_mutex);
-/*
- function that is activated on the successfull probe of the RAR device
-*/
-static int __devinit rar_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
+struct RAR_device {
+ struct RAR_offsets const rar_offsets[MRST_NUM_RAR];
+ struct RAR_address_range rar_addr[MRST_NUM_RAR];
+ struct pci_dev *rar_dev;
+ bool registered;
+ };
-static struct pci_device_id rar_pci_id_tbl[] = {
- { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x4110) },
- { 0 }
+/* this platform has only one rar_device for 3 rar regions */
+static struct RAR_device my_rar_device = {
+ .rar_offsets = {
+ [0].low = LNC_BRAR0L,
+ [0].high = LNC_BRAR0H,
+ [1].low = LNC_BRAR1L,
+ [1].high = LNC_BRAR1H,
+ [2].low = LNC_BRAR2L,
+ [2].high = LNC_BRAR2H
+ }
};
-MODULE_DEVICE_TABLE(pci, rar_pci_id_tbl);
+/* this data is for handling requests from other drivers which arrive
+ * prior to this driver initializing
+ */
-/* field for registering driver to PCI device */
-static struct pci_driver rar_pci_driver = {
- .name = "rar_driver",
- .id_table = rar_pci_id_tbl,
- .probe = rar_probe
-};
+static struct client clients[MAX_RAR_CLIENTS];
+static int num_clients;
-/* This function is used to retrieved RAR info using the IPC message
- bus interface */
-static int memrar_get_rar_addr(struct pci_dev* pdev,
- int offset,
- u32 *addr)
+/*
+ * This function is used to retrieved RAR info using the Lincroft
+ * message bus interface.
+ */
+static int retrieve_rar_addr(struct pci_dev *pdev,
+ int offset,
+ dma_addr_t *addr)
{
/*
* ======== The Lincroft Message Bus Interface ========
@@ -131,291 +180,216 @@ static int memrar_get_rar_addr(struct pci_dev* pdev,
* Data being written to this register must be written before
* writing the appropriate control message to the MCR
* register.
- */
+ */
+
+ int result;
- int result = 0; /* result */
/* Construct control message */
u32 const message =
- (LNC_MESSAGE_READ_OPCODE << 24)
- | (LNC_BUNIT_PORT << 16)
- | (offset << 8)
- | (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
+ (LNC_MESSAGE_READ_OPCODE << 24)
+ | (LNC_BUNIT_PORT << 16)
+ | (offset << 8)
+ | (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
- printk(KERN_WARNING "rar- offset to LNC MSG is %x\n",offset);
+ dev_dbg(&pdev->dev, "Offset for 'get' LNC MSG is %x\n", offset);
- if (addr == 0)
+ if (addr == 0) {
+ WARN_ON(1);
return -EINVAL;
+ }
+
+ /*
+ * 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);
+ result = pci_write_config_dword(pdev, LNC_MCR_OFFSET, message);
- printk(KERN_WARNING "rar- result from send ctl register is %x\n"
- ,result);
+ dev_dbg(&pdev->dev, "Result from send ctl register is %x\n", result);
- if (!result)
- result = pci_read_config_dword(pdev,
- LNC_MDR_OFFSET,
- addr);
+ if (!result) {
+ result = pci_read_config_dword(pdev, LNC_MDR_OFFSET,
+ (u32 *)addr);
+ dev_dbg(&pdev->dev,
+ "Result from read data register is %x\n", result);
- printk(KERN_WARNING "rar- result from read data register is %x\n",
- result);
+ dev_dbg(&pdev->dev,
+ "Value read from data register is %Lx\n", *addr);
+ }
- printk(KERN_WARNING "rar- value read from data register is %x\n",
- *addr);
+ mutex_unlock(&lnc_reg_mutex);
- if (result)
- return -1;
- else
- return 0;
+ return result;
}
-static int memrar_set_rar_addr(struct pci_dev* pdev,
- int offset,
- u32 addr)
+static int set_rar_address(struct pci_dev *pdev,
+ int offset,
+ dma_addr_t addr)
{
/*
- * ======== The Lincroft Message Bus Interface ========
- * Lincroft registers may be obtained from the PCI
- * (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.
- */
+ * Data being written to this register must be written before
+ * writing the appropriate control message to the MCR
+ * register.
+ * @note See rar_get_address() for a description of the
+ * message bus interface being used here.
+ */
- int result = 0; /* result */
+ int result = 0;
/* Construct control message */
- u32 const message =
- (LNC_MESSAGE_WRITE_OPCODE << 24)
- | (LNC_BUNIT_PORT << 16)
- | (offset << 8)
- | (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
-
- printk(KERN_WARNING "rar- offset to LNC MSG is %x\n",offset);
+ u32 const message = (LNC_MESSAGE_WRITE_OPCODE << 24)
+ | (LNC_BUNIT_PORT << 16)
+ | (offset << 8)
+ | (LNC_MESSAGE_BYTE_WRITE_ENABLES << 4);
- if (addr == 0)
+ if (addr == 0) {
+ WARN_ON(1);
return -EINVAL;
+ }
- /* Send the control message */
- result = pci_write_config_dword(pdev,
- LNC_MDR_OFFSET,
- addr);
-
- printk(KERN_WARNING "rar- result from send ctl register is %x\n"
- ,result);
-
- if (!result)
- result = pci_write_config_dword(pdev,
- LNC_MCR_OFFSET,
- message);
+ dev_dbg(&pdev->dev, "Offset for 'set' LNC MSG is %x\n", offset);
- printk(KERN_WARNING "rar- result from write data register is %x\n",
- result);
+ /*
+ * 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.
+ */
- printk(KERN_WARNING "rar- value read to data register is %x\n",
- addr);
+ mutex_lock(&lnc_reg_mutex);
- if (result)
- return -1;
- else
- return 0;
-}
+ /* Send the control message */
+ result = pci_write_config_dword(pdev, LNC_MDR_OFFSET, addr);
-/*
+ dev_dbg(&pdev->dev, "Result from write data register is %x\n", result);
- * Initialize RAR parameters, such as physical addresses, etc.
+ if (!result) {
+ dev_dbg(&pdev->dev,
+ "Value written to data register is %Lx\n", addr);
- */
-static int memrar_init_rar_params(struct pci_dev *pdev)
-{
- struct RAR_offsets const offsets[] = {
- { LNC_BRAR0L, LNC_BRAR0H },
- { LNC_BRAR1L, LNC_BRAR1H },
- { LNC_BRAR2L, LNC_BRAR2H }
- };
-
- size_t const num_offsets = sizeof(offsets) / sizeof(offsets[0]);
- struct RAR_offsets const *end = offsets + num_offsets;
- struct RAR_offsets const *i;
- unsigned int n = 0;
- int result = 0;
+ result = pci_write_config_dword(pdev, LNC_MCR_OFFSET, message);
- /* Retrieve RAR start and end physical addresses. */
-
- /*
- * Access the RAR registers through the Lincroft Message Bus
- * Interface on PCI device: 00:00.0 Host bridge.
- */
-
- /* struct pci_dev *pdev = pci_get_bus_and_slot(0, PCI_DEVFN(0,0)); */
-
- if (pdev == NULL)
- return -ENODEV;
-
- for (i = offsets; i != end; ++i, ++n) {
- if (memrar_get_rar_addr (pdev,
- (*i).low,
- &(rar_addr[n].low)) != 0
- || memrar_get_rar_addr (pdev,
- (*i).high,
- &(rar_addr[n].high)) != 0) {
- result = -1;
- break;
- }
+ dev_dbg(&pdev->dev, "Result from send ctl register is %x\n",
+ result);
}
- /* Done accessing the device. */
- /* pci_dev_put(pdev); */
-
- if (result == 0) {
- if(1) {
- size_t z;
- for (z = 0; z != MRST_NUM_RAR; ++z) {
- printk(KERN_WARNING "rar - BRAR[%Zd] physical address low\n"
- "\tlow: 0x%08x\n"
- "\thigh: 0x%08x\n",
- z,
- rar_addr[z].low,
- rar_addr[z].high);
- }
- }
- }
+ mutex_unlock(&lnc_reg_mutex);
return result;
}
/*
- function that is activated on the successfull probe of the RAR device
+* Initialize RAR parameters, such as bus addresses, etc.
*/
-static int __devinit rar_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+static int init_rar_params(struct pci_dev *pdev)
{
- /* error */
- int error;
-
- /*------------------------
- CODE
- ---------------------------*/
-
- DEBUG_PRINT_0(RAR_DEBUG_LEVEL_EXTENDED,
- "Rar pci probe starting\n");
- error = 0;
-
- /* enable the device */
- error = pci_enable_device(pdev);
- if (error) {
- DEBUG_PRINT_0(RAR_DEBUG_LEVEL_EXTENDED,
- "error enabling pci device\n");
- goto end_function;
- }
+ unsigned int i;
+ int result = 0;
- rar_dev = pdev;
- registered = 1;
+ /* 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.
+ */
- /* Initialize the RAR parameters, which have to be retrieved */
- /* via the message bus service */
- error=memrar_init_rar_params(rar_dev);
+ for (i = 0; i < MRST_NUM_RAR; ++i) {
+ struct RAR_offsets const *offset =
+ &my_rar_device.rar_offsets[i];
+ struct RAR_address_range *addr = &my_rar_device.rar_addr[i];
- if (error) {
- DEBUG_PRINT_0(RAR_DEBUG_LEVEL_EXTENDED,
- "error getting RAR addresses device\n");
- registered = 0;
- goto end_function;
+ if ((retrieve_rar_addr(pdev, offset->low, &addr->low) != 0)
+ || (retrieve_rar_addr(pdev, offset->high, &addr->high) != 0)) {
+ result = -1;
+ break;
}
-end_function:
+ /*
+ * 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.
- return error;
-}
+ * The low address has its lower 10 bits cleared, and
+ * the high address has all its lower 10 bits set,
+ * e.g.:
+ * low = 0x2ffffc00
+ */
-/*
- this function registers th driver to
- the device subsystem( either PCI, USB, etc)
-*/
-static int __init rar_init_handler(void)
-{
- return pci_register_driver(&rar_pci_driver);
-}
+ addr->low &= (dma_addr_t)0xfffffc00u;
-static void __exit rar_exit_handler(void)
-{
- pci_unregister_driver(&rar_pci_driver);
-}
+ /*
+ * Set bits 9:0 on uppser address if bits 31:10 are non
+ * zero; otherwize clear all bits
+ */
-module_init(rar_init_handler);
-module_exit(rar_exit_handler);
+ if ((addr->high & 0xfffffc00u) == 0)
+ addr->high = 0;
+ else
+ addr->high |= 0x3ffu;
+ }
+ /* Done accessing the device. */
-MODULE_LICENSE("GPL");
+ if (result == 0) {
+ int z;
+ for (z = 0; z != MRST_NUM_RAR; ++z) {
+ /*
+ * "BRAR" refers to the RAR registers in the
+ * Lincroft B-unit.
+ */
+ dev_info(&pdev->dev, "BRAR[%u] bus address range = "
+ "[%Lx, %Lx]\n", z,
+ my_rar_device.rar_addr[z].low,
+ my_rar_device.rar_addr[z].high);
+ }
+ }
+ return result;
+}
-/* The get_rar_address function is used by other device drivers
- * to obtain RAR address information on a RAR. It takes two
- * parameter:
+/*
+ * The rar_get_address function is used by other device drivers
+ * to obtain RAR address information on a RAR. It takes three
+ * parameters:
*
* int rar_index
* The rar_index is an index to the rar for which you wish to retrieve
* the address information.
* Values can be 0,1, or 2.
*
- * struct RAR_address_struct is a pointer to a place to which the function
- * can return the address structure for the RAR.
- *
* The function returns a 0 upon success or a -1 if there is no RAR
* facility on this system.
*/
-int get_rar_address(int rar_index,struct RAR_address_struct *addresses)
+int rar_get_address(int rar_index,
+ dma_addr_t *start_address,
+ dma_addr_t *end_address)
{
- if (registered && (rar_index < 3) && (rar_index >= 0)) {
- *addresses=rar_addr[rar_index];
- /* strip off lock bit information */
- addresses->low = addresses->low & 0xfffffff0;
- addresses->high = addresses->high & 0xfffffff0;
- return 0;
+ int result = -ENODEV;
+
+ if (my_rar_device.registered) {
+ if (start_address == 0 || end_address == 0
+ || rar_index >= MRST_NUM_RAR || rar_index < 0) {
+ result = -EINVAL;
+ } else {
+ *start_address =
+ my_rar_device.rar_addr[rar_index].low;
+ *end_address =
+ my_rar_device.rar_addr[rar_index].high;
+
+ result = 0;
}
+ }
- else {
- return -ENODEV;
- }
+ return result;
}
+EXPORT_SYMBOL(rar_get_address);
-
-EXPORT_SYMBOL(get_rar_address);
-
-/* The lock_rar function is ued by other device drivers to lock an RAR.
+/*
+ * The rar_lock function is ued by other device drivers to lock an RAR.
* once an RAR is locked, it stays locked until the next system reboot.
* The function takes one parameter:
*
@@ -426,20 +400,218 @@ EXPORT_SYMBOL(get_rar_address);
* The function returns a 0 upon success or a -1 if there is no RAR
* facility on this system.
*/
-int lock_rar(int rar_index)
+int rar_lock(int rar_index)
{
- u32 working_addr;
- int result;
-if (registered && (rar_index < 3) && (rar_index >= 0)) {
- /* first make sure that lock bits are clear (this does lock) */
- working_addr=rar_addr[rar_index].low & 0xfffffff0;
+ int result = -ENODEV;
+
+ if (rar_index >= MRST_NUM_RAR || rar_index < 0) {
+ result = -EINVAL;
+ return result;
+ }
+
+ dev_dbg(&my_rar_device.rar_dev->dev, "rar_lock mutex locking\n");
+ mutex_lock(&rar_mutex);
+
+ if (my_rar_device.registered) {
+
+ dma_addr_t low = my_rar_device.rar_addr[rar_index].low &
+ 0xfffffc00u;
+
+ dma_addr_t high = my_rar_device.rar_addr[rar_index].high &
+ 0xfffffc00u;
+
+ /*
+ * Only allow I/O from the graphics and Langwell;
+ * Not from the x96 processor
+ */
+ if (rar_index == (int)RAR_TYPE_VIDEO) {
+ low |= 0x00000009;
+ high |= 0x00000015;
+ }
+
+ else if (rar_index == (int)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 = set_rar_address(my_rar_device.rar_dev,
+ my_rar_device.rar_offsets[rar_index].low,
+ low);
+
+ if (result == 0)
+ result = set_rar_address(
+ my_rar_device.rar_dev,
+ my_rar_device.rar_offsets[rar_index].high,
+ high);
+ }
+
+ dev_dbg(&my_rar_device.rar_dev->dev, "rar_lock mutex unlocking\n");
+ mutex_unlock(&rar_mutex);
+ return result;
+}
+EXPORT_SYMBOL(rar_lock);
+
+/* 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 dirvers 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 an -1 on failure.
+*/
+int register_rar(int (*callback)(void *yourparameter), void *yourparameter)
+{
+
+ int result = -ENODEV;
+
+ if (callback == NULL)
+ return -EINVAL;
+
+ dev_dbg(&my_rar_device.rar_dev->dev, "register_rar locking\n");
+ mutex_lock(&rar_mutex);
+
+ if (my_rar_device.registered) {
+
+ /*
+ * if the driver already registered, then we can simply
+ * call the callback right now
+ */
+
+ result = (*callback)(yourparameter);
+ if (result) {
+ dev_dbg(&my_rar_device.rar_dev->dev,
+ "Immediate Callback failed: %x\n",
+ result);
+ } else {
+ dev_dbg(&my_rar_device.rar_dev->dev,
+ "Immediate Callback ran okay\n");
+ }
+
+ dev_dbg(&my_rar_device.rar_dev->dev,
+ "register_rar unlocking\n");
+ mutex_unlock(&rar_mutex);
+ return result;
+ }
+
+ if (num_clients < MRST_NUM_RAR) {
- /* now send that value to the register using the IPC */
- result=memrar_set_rar_addr(rar_dev,rar_index,working_addr);
+ clients[num_clients].client_callback = callback;
+ clients[num_clients].customer_data = yourparameter;
+ num_clients += 1;
+ dev_dbg(&my_rar_device.rar_dev->dev, "Callback registered\n");
+ result = 0;
+ }
+
+ dev_dbg(&my_rar_device.rar_dev->dev,
+ "register_rar unlocking\n");
+ mutex_unlock(&rar_mutex);
return result;
+
+}
+EXPORT_SYMBOL(register_rar);
+
+/*
+ * This function registers the driver with the device subsystem (
+ * either PCI, USB, etc).
+ * Function that is activaed on the succesful probe of the RAR device
+ * (Moorestown host controller).
+ */
+static int rar_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+ int error;
+ int counter;
+
+ dev_dbg(&dev->dev, "PCI probe starting\n");
+
+ /* enable the device */
+ error = pci_enable_device(dev);
+ if (error) {
+ dev_err(&dev->dev,
+ "Error enabling RAR register PCI device\n");
+ goto end_function;
}
-else {
- return -ENODEV;
+ /* we have only one device; fill in the rar_device structure */
+ my_rar_device.rar_dev = dev;
+
+ /*
+ * Initialize the RAR parameters, which have to be retrieved
+ * via the message bus interface.
+ */
+ error = init_rar_params(dev);
+ if (error) {
+ pci_disable_device(dev);
+
+ dev_err(&dev->dev,
+ "Error retrieving RAR addresses\n");
+
+ goto end_function;
+ }
+
+ dev_dbg(&dev->dev, "PCI probe locking\n");
+ mutex_lock(&rar_mutex);
+ my_rar_device.registered = 1;
+
+ /* now call anyone who has registered (using callbacks) */
+ for (counter = 0; counter < num_clients; counter += 1) {
+ if (clients[counter].client_callback) {
+ error = (*clients[counter].client_callback)(
+ clients[counter].customer_data);
+ /* set callback to NULL to indicate it has been done */
+ clients[counter].client_callback = NULL;
+ dev_dbg(&my_rar_device.rar_dev->dev,
+ "Callback called for %d\n",
+ counter);
+ }
}
+
+ dev_dbg(&dev->dev, "PCI probe unlocking\n");
+ mutex_unlock(&rar_mutex);
+
+end_function:
+
+ return error;
}
+
+const struct pci_device_id rar_pci_id_tbl[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_RAR_DEVICE_ID) },
+ { 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
+};
+
+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");
--
1.6.0.6
--
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