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authorHarald Welte <laforge@gnumonks.org>2011-07-24 09:39:28 +0200
committerHarald Welte <laforge@gnumonks.org>2011-07-24 09:39:28 +0200
commit98f9d442b44dbe2e3e4b3c8296be7e78d5d05450 (patch)
treee9d0a9c86ce3645926c3206f83026deff142af25 /at91lib/peripherals/cp15
initial import of the usb ccid example for the sam7s
Diffstat (limited to 'at91lib/peripherals/cp15')
-rw-r--r--at91lib/peripherals/cp15/cp15.c268
-rw-r--r--at91lib/peripherals/cp15/cp15.h84
-rw-r--r--at91lib/peripherals/cp15/cp15_asm.S138
3 files changed, 490 insertions, 0 deletions
diff --git a/at91lib/peripherals/cp15/cp15.c b/at91lib/peripherals/cp15/cp15.c
new file mode 100644
index 0000000..17a1f70
--- /dev/null
+++ b/at91lib/peripherals/cp15/cp15.c
@@ -0,0 +1,268 @@
+/* ----------------------------------------------------------------------------
+ * ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2008, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+//-----------------------------------------------------------------------------
+// Headers
+//-----------------------------------------------------------------------------
+
+#include <board.h>
+
+#ifdef CP15_PRESENT
+
+#include <utility/trace.h>
+#include "cp15.h"
+
+#if defined(__ICCARM__)
+#include <intrinsics.h>
+#endif
+
+
+//-----------------------------------------------------------------------------
+// Macros
+//-----------------------------------------------------------------------------
+
+//-----------------------------------------------------------------------------
+// Defines
+//-----------------------------------------------------------------------------
+/*
+#define CP15_RR_BIT 14 // RR bit Replacement strategy for ICache and DCache:
+ // 0 = Random replacement
+ // 1 = Round-robin replacement.
+
+#define CP15_V_BIT 13 // V bit Location of exception vectors:
+ // 0 = Normal exception vectors selected address range = 0x0000 0000 to 0x0000 001C
+ // 1 = High exception vect selected, address range = 0xFFFF 0000 to 0xFFFF 001C
+*/
+#define CP15_I_BIT 12 // I bit ICache enable/disable:
+ // 0 = ICache disabled
+ // 1 = ICache enabled
+/*
+#define CP15_R_BIT 9 // R bit ROM protection
+
+#define CP15_S_BIT 8 // S bit System protection
+
+#define CP15_B_BIT 7 // B bit Endianness:
+ // 0 = Little-endian operation
+ // 1 = Big-endian operation.
+*/
+#define CP15_C_BIT 2 // C bit DCache enable/disable:
+ // 0 = Cache disabled
+ // 1 = Cache enabled
+/*
+#define CP15_A_BIT 1 // A bit Alignment fault enable/disable:
+ // 0 = Data address alignment fault checking disabled
+ // 1 = Data address alignment fault checking enabled
+*/
+#define CP15_M_BIT 0 // M bit MMU enable/disable: 0 = disabled 1 = enabled.
+ // 0 = disabled
+ // 1 = enabled
+
+
+//-----------------------------------------------------------------------------
+// Global functions
+//-----------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+/// Check Instruction Cache
+/// \return 0 if I_Cache disable, 1 if I_Cache enable
+//------------------------------------------------------------------------------
+unsigned int CP15_Is_I_CacheEnabled(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+ return ((control & (1 << CP15_I_BIT)) != 0);
+}
+
+//------------------------------------------------------------------------------
+/// Enable Instruction Cache
+//------------------------------------------------------------------------------
+void CP15_Enable_I_Cache(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ // Check if cache is disabled
+ if ((control & (1 << CP15_I_BIT)) == 0) {
+
+ control |= (1 << CP15_I_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("I cache enabled.\n\r");
+ }
+#if !defined(OP_BOOTSTRAP_on)
+ else {
+
+ TRACE_INFO("I cache is already enabled.\n\r");
+ }
+#endif
+}
+
+//------------------------------------------------------------------------------
+/// Disable Instruction Cache
+//------------------------------------------------------------------------------
+void CP15_Disable_I_Cache(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ // Check if cache is enabled
+ if ((control & (1 << CP15_I_BIT)) != 0) {
+
+ control &= ~(1 << CP15_I_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("I cache disabled.\n\r");
+ }
+ else {
+
+ TRACE_INFO("I cache is already disabled.\n\r");
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Check MMU
+/// \return 0 if MMU disable, 1 if MMU enable
+//------------------------------------------------------------------------------
+unsigned int CP15_Is_MMUEnabled(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+ return ((control & (1 << CP15_M_BIT)) != 0);
+}
+
+//------------------------------------------------------------------------------
+/// Enable MMU
+//------------------------------------------------------------------------------
+void CP15_EnableMMU(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ // Check if MMU is disabled
+ if ((control & (1 << CP15_M_BIT)) == 0) {
+
+ control |= (1 << CP15_M_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("MMU enabled.\n\r");
+ }
+ else {
+
+ TRACE_INFO("MMU is already enabled.\n\r");
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Disable MMU
+//------------------------------------------------------------------------------
+void CP15_DisableMMU(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ // Check if MMU is enabled
+ if ((control & (1 << CP15_M_BIT)) != 0) {
+
+ control &= ~(1 << CP15_M_BIT);
+ control &= ~(1 << CP15_C_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("MMU disabled.\n\r");
+ }
+ else {
+
+ TRACE_INFO("MMU is already disabled.\n\r");
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Check D_Cache
+/// \return 0 if D_Cache disable, 1 if D_Cache enable (with MMU of course)
+//------------------------------------------------------------------------------
+unsigned int CP15_Is_DCacheEnabled(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+ return ((control & ((1 << CP15_C_BIT)||(1 << CP15_M_BIT))) != 0);
+}
+
+//------------------------------------------------------------------------------
+/// Enable Data Cache
+//------------------------------------------------------------------------------
+void CP15_Enable_D_Cache(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ if( !CP15_Is_MMUEnabled() ) {
+ TRACE_ERROR("Do nothing: MMU not enabled\n\r");
+ }
+ else {
+ // Check if cache is disabled
+ if ((control & (1 << CP15_C_BIT)) == 0) {
+
+ control |= (1 << CP15_C_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("D cache enabled.\n\r");
+ }
+ else {
+
+ TRACE_INFO("D cache is already enabled.\n\r");
+ }
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Disable Data Cache
+//------------------------------------------------------------------------------
+void CP15_Disable_D_Cache(void)
+{
+ unsigned int control;
+
+ control = _readControlRegister();
+
+ // Check if cache is enabled
+ if ((control & (1 << CP15_C_BIT)) != 0) {
+
+ control &= ~(1 << CP15_C_BIT);
+ _writeControlRegister(control);
+ TRACE_INFO("D cache disabled.\n\r");
+ }
+ else {
+
+ TRACE_INFO("D cache is already disabled.\n\r");
+ }
+}
+
+#endif // CP15_PRESENT
+
diff --git a/at91lib/peripherals/cp15/cp15.h b/at91lib/peripherals/cp15/cp15.h
new file mode 100644
index 0000000..ddaaeb6
--- /dev/null
+++ b/at91lib/peripherals/cp15/cp15.h
@@ -0,0 +1,84 @@
+/* ----------------------------------------------------------------------------
+ * ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2008, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+//------------------------------------------------------------------------------
+/// \unit
+///
+/// !Purpose
+///
+/// Methods to manage the Coprocessor 15. Coprocessor 15, or System Control
+/// Coprocessor CP15, is used to configure and control all the items in the
+/// list below:
+/// • ARM core
+/// • Caches (ICache, DCache and write buffer)
+/// • TCM
+/// • MMU
+/// • Other system options
+///
+/// !Usage
+///
+/// -# Enable or disable D cache with Enable_D_Cache and Disable_D_Cache
+/// -# Enable or disable I cache with Enable_I_Cache and Disable_I_Cache
+///
+//------------------------------------------------------------------------------
+
+#ifndef _CP15_H
+#define _CP15_H
+
+#ifdef CP15_PRESENT
+
+//-----------------------------------------------------------------------------
+// Exported functions
+//-----------------------------------------------------------------------------
+extern void CP15_Enable_I_Cache(void);
+extern unsigned int CP15_Is_I_CacheEnabled(void);
+extern void CP15_Enable_I_Cache(void);
+extern void CP15_Disable_I_Cache(void);
+extern unsigned int CP15_Is_MMUEnabled(void);
+extern void CP15_EnableMMU(void);
+extern void CP15_DisableMMU(void);
+extern unsigned int CP15_Is_DCacheEnabled(void);
+extern void CP15_Enable_D_Cache(void);
+extern void CP15_Disable_D_Cache(void);
+
+//-----------------------------------------------------------------------------
+// External functions defined in cp15.S
+//-----------------------------------------------------------------------------
+extern unsigned int _readControlRegister(void);
+extern void _writeControlRegister(unsigned int value);
+extern void _waitForInterrupt(void);
+extern void _writeTTB(unsigned int value);
+extern void _writeDomain(unsigned int value);
+extern void _writeITLBLockdown(unsigned int value);
+extern void _prefetchICacheLine(unsigned int value);
+
+#endif // CP15_PRESENT
+
+#endif // #ifndef _CP15_H
+
diff --git a/at91lib/peripherals/cp15/cp15_asm.S b/at91lib/peripherals/cp15/cp15_asm.S
new file mode 100644
index 0000000..00ef47d
--- /dev/null
+++ b/at91lib/peripherals/cp15/cp15_asm.S
@@ -0,0 +1,138 @@
+/* ----------------------------------------------------------------------------
+ * ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2008, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+//------------------------------------------------------------------------------
+// Headers
+//------------------------------------------------------------------------------
+
+#define __ASSEMBLY__
+#include "board.h"
+
+#ifdef CP15_PRESENT
+
+//------------------------------------------------------------------------------
+/// Functions to access CP15 coprocessor register
+//------------------------------------------------------------------------------
+
+ .global _readControlRegister
+ .global _writeControlRegister
+ .global _waitForInterrupt
+ .global _writeTTB
+ .global _writeDomain
+ .global _writeITLBLockdown
+ .global _prefetchICacheLine
+
+//------------------------------------------------------------------------------
+/// Control Register c1
+/// Register c1 is the Control Register for the ARM926EJ-S processor.
+/// This register specifies the configuration used to enable and disable the
+/// caches and MMU. It is recommended that you access this register using a
+/// read-modify-write sequence.
+//------------------------------------------------------------------------------
+// CP15 Read Control Register
+_readControlRegister:
+ mov r0, #0
+ mrc p15, 0, r0, c1, c0, 0
+ bx lr
+
+// CP15 Write Control Register
+_writeControlRegister:
+ mcr p15, 0, r0, c1, c0, 0
+ bx lr
+
+//------------------------------------------------------------------------------
+/// CP15 Wait For Interrupt operation
+/// The purpose of the Wait For Interrupt operation is to put the processor in
+/// to a low power state.
+/// This puts the processor into a low-power state and stops it executing more
+/// instructions until an interrupt, or debug request occurs, regardless of
+/// whether the interrupts are disabled by the masks in the CPSR.
+/// When an interrupt does occur, the MCR instruction completes and the IRQ or
+/// FIQ handler is entered as normal. The return link in r14_irq or r14_fiq
+/// contains the address of the MCR instruction plus 8, so that the normal
+/// instruction used for interrupt return (SUBS PC,R14,#4) returns to the
+/// instruction following the MCR.
+/// Wait For Interrupt : MCR p15, 0, <Rd>, c7, c0, 4
+//------------------------------------------------------------------------------
+_waitForInterrupt:
+ mov r0, #0
+ mcr p15, 0, r0, c7, c0, 4
+ bx lr
+
+//------------------------------------------------------------------------------
+/// CP15 Translation Table Base Register c2
+/// Register c2 is the Translation Table Base Register (TTBR), for the base
+/// address of the first-level translation table.
+/// Reading from c2 returns the pointer to the currently active first-level
+/// translation table in bits [31:14] and an Unpredictable value in bits [13:0].
+/// Writing to register c2 updates the pointer to the first-level translation
+/// table from the value in bits [31:14] of the written value. Bits [13:0]
+/// Should Be Zero.
+/// You can use the following instructions to access the TTBR:
+/// Read TTBR : MRC p15, 0, <Rd>, c2, c0, 0
+/// Write TTBR : MCR p15, 0, <Rd>, c2, c0, 0
+//------------------------------------------------------------------------------
+_writeTTB:
+ MCR p15, 0, r0, c2, c0, 0
+ bx lr
+
+//------------------------------------------------------------------------------
+/// Domain Access Control Register c3
+/// Read domain access permissions : MRC p15, 0, <Rd>, c3, c0, 0
+/// Write domain access permissions : MCR p15, 0, <Rd>, c3, c0, 0
+//------------------------------------------------------------------------------
+_writeDomain:
+ MCR p15, 0, r0, c3, c0, 0
+ bx lr
+
+//------------------------------------------------------------------------------
+/// TLB Lockdown Register c10
+/// The TLB Lockdown Register controls where hardware page table walks place the
+/// TLB entry, in the set associative region or the lockdown region of the TLB,
+/// and if in the lockdown region, which entry is written. The lockdown region
+/// of the TLB contains eight entries. See TLB structure for a description of
+/// the structure of the TLB.
+/// Read data TLB lockdown victim : MRC p15,0,<Rd>,c10,c0,0
+/// Write data TLB lockdown victim : MCR p15,0,<Rd>,c10,c0,0
+//------------------------------------------------------------------------------
+_writeITLBLockdown:
+ MCR p15, 0, r0, c10, c0, 0
+ bx lr
+
+//------------------------------------------------------------------------------
+/// Prefetch ICache line
+/// Performs an ICache lookup of the specified modified virtual address.
+/// If the cache misses, and the region is cacheable, a linefill is performed.
+/// Prefetch ICache line (MVA): MCR p15, 0, <Rd>, c7, c13, 1
+//------------------------------------------------------------------------------
+_prefetchICacheLine:
+ MCR p15, 0, r0, c7, c13, 1
+ bx lr
+#endif
+
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