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authorAlan Cox <alan@linux.intel.com>2010-06-18 14:05:52 +0100
committerMatthew Garrett <mjg@redhat.com>2010-08-03 09:48:50 -0400
commitc715a38bb7fc22fb8018b916c8a9f7ff017a8ad7 (patch)
treeb51c087653a2e6cd9a03057cf995eca3100bfb0e /drivers/platform
parent97ba0af097dc3428b85dc6a1282968d7ba9510f5 (diff)
downloadblackbird-op-linux-c715a38bb7fc22fb8018b916c8a9f7ff017a8ad7.tar.gz
blackbird-op-linux-c715a38bb7fc22fb8018b916c8a9f7ff017a8ad7.zip
rar: Move the RAR driver into the right place as its now clean
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>
Diffstat (limited to 'drivers/platform')
-rw-r--r--drivers/platform/x86/Kconfig22
-rw-r--r--drivers/platform/x86/Makefile1
-rw-r--r--drivers/platform/x86/intel_rar_register.c671
3 files changed, 694 insertions, 0 deletions
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 724b2ed1a3cb..2f173bc0ff05 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -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
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 7318fc2c1629..ed50eca1b556 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -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
diff --git a/drivers/platform/x86/intel_rar_register.c b/drivers/platform/x86/intel_rar_register.c
new file mode 100644
index 000000000000..73f8e6d72669
--- /dev/null
+++ b/drivers/platform/x86/intel_rar_register.c
@@ -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");
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