ENGR00142679 SCC2 and SAHARA: changes to support loadable modules

To allow SCC2 and SAHARA drivers to work as loadable modules, needed
to add GPL license to SAHARA driver, export a couple of functions
from SCC2 driver, and the following data buffer mapping change in
SAHARA driver:

When compiled as a loadable module, a data buffer to be DMA'ed in the
SAHARA driver may not be in the kernel direct-mapped region but in
the "Kernel module space" between TASK_SIZE and high_memory-1
(see http://www.arm.linux.org.uk/developer/memory.txt). In this
scenario, the driver canno simply use the __pa macro to obtain
the physical address. It must walk the page tables to find the
page and use the page_to_phys function to find the physical
address that corresponds to the data buffer.

Signed-off-by: Anish Trivedi <anish@freescale.com>

4 files changed, 22 insertions, 5 deletions

diff --git a/drivers/mxc/security/sahara2/sah_driver_interface.c b/drivers/mxc/security/sahara2/sah_driver_interface.c
index cf01c5f8bfe0..015865f99873 100644
--- a/drivers/mxc/security/sahara2/sah_driver_interface.c
+++ b/drivers/mxc/security/sahara2/sah_driver_interface.c
@@ -48,6 +48,10 @@
 #define interruptible_sleep_on(x) sah_Handle_Interrupt()
 #endif
 
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Freescale Semiconductor");
+MODULE_DESCRIPTION("Device Driver for SAHARA2 crypto hw block");
+
 #define TEST_MODE_OFF 1
 #define TEST_MODE_ON 2
 
diff --git a/drivers/mxc/security/sahara2/sah_memory_mapper.c b/drivers/mxc/security/sahara2/sah_memory_mapper.c
index 2e3b80b14873..f863b0300c8f 100644
--- a/drivers/mxc/security/sahara2/sah_memory_mapper.c
+++ b/drivers/mxc/security/sahara2/sah_memory_mapper.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2004-2011 Freescale Semiconductor, Inc. All Rights Reserved.
  */
 
 /*
@@ -750,6 +750,7 @@ sah_Head_Desc *sah_Copy_Descriptors(fsl_shw_uco_t * user_ctx,
 sah_Link *sah_Physicalise_Links(sah_Link * first_link)
 {
 	sah_Link *link = first_link;
+	struct page *pg;
 
 	while (link != NULL) {
 #ifdef DO_DBG
@@ -814,8 +815,18 @@ sah_Link *sah_Physicalise_Links(sah_Link * first_link)
 			if (!(link->flags & SAH_PREPHYS_DATA)) {
 				link->original_data = link->data;
 
-				/* All pointers are virtual right now */
-				link->data = (void *)os_pa(link->data);
+				/* if the data buffer is not in kernel direct-
+				  * mapped region, find the physical addr
+				  * via other means.
+				  */
+				if (!virt_addr_valid(link->data)) {
+					pg = vmalloc_to_page(link->data);
+					link->data = (uint8_t *) (
+						page_to_phys(pg) +
+						(((unsigned int) link->data) &
+							~PAGE_MASK));
+				} else
+					link->data = (void *)os_pa(link->data);
 #ifdef DO_DBG
 				os_printk("%sput: %p (%d)\n",
 					  (link->
diff --git a/drivers/mxc/security/scc2_driver.c b/drivers/mxc/security/scc2_driver.c
index 358d516676f7..bc2d56c79e67 100644
--- a/drivers/mxc/security/scc2_driver.c
+++ b/drivers/mxc/security/scc2_driver.c
@@ -377,7 +377,7 @@ scc_return_t scc_diminish_permissions(void *part_base, uint32_t permissions)
 	return SCC_RET_FAIL;
 }
 
-extern scc_partition_status_t scc_partition_status(void *part_base)
+scc_partition_status_t scc_partition_status(void *part_base)
 {
 	uint32_t part_no;
 	uint32_t part_owner;
diff --git a/drivers/mxc/security/scc2_internals.h b/drivers/mxc/security/scc2_internals.h
index 1c047de0082e..c1a4e4c86829 100644
--- a/drivers/mxc/security/scc2_internals.h
+++ b/drivers/mxc/security/scc2_internals.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2004-2011 Freescale Semiconductor, Inc. All Rights Reserved.
  */
 
 /*
@@ -507,6 +507,8 @@ EXPORT_SYMBOL(scc_release_partition);
 EXPORT_SYMBOL(scc_diminish_permissions);
 EXPORT_SYMBOL(scc_encrypt_region);
 EXPORT_SYMBOL(scc_decrypt_region);
+EXPORT_SYMBOL(scc_partition_status);
+EXPORT_SYMBOL(scc_virt_to_phys);
 /*EXPORT_SYMBOL(make_vpu_partition);*/