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-rw-r--r--cpu/mpc824x/drivers/epic/README104
-rw-r--r--cpu/mpc824x/drivers/epic/epic2.S196
-rw-r--r--cpu/mpc824x/drivers/epic/epicutil.S58
3 files changed, 358 insertions, 0 deletions
diff --git a/cpu/mpc824x/drivers/epic/README b/cpu/mpc824x/drivers/epic/README
new file mode 100644
index 0000000..ae95b88
--- /dev/null
+++ b/cpu/mpc824x/drivers/epic/README
@@ -0,0 +1,104 @@
+CONTENT:
+
+ epic.h
+ epic1.c
+ epic2.s
+
+WHAT ARE THESE FILES:
+
+These files contain MPC8240 (Kahlua) EPIC
+driver routines. The driver routines are not
+written for any specific operating system.
+They serves the purpose of code sample, and
+jump-start for using the MPC8240 EPIC unit.
+
+For the reason of correctness of C language
+syntax, these files are compiled by Metaware
+C compiler and assembler.
+
+ENDIAN NOTATION:
+
+The algorithm is designed for big-endian mode,
+software is responsible for byte swapping.
+
+USAGE:
+
+1. The host system that is running on MPC8240
+ shall link the files listed here. The memory
+ location of driver routines shall take into
+ account of that driver routines need to run
+ in supervisor mode and they process external
+ interrupts.
+
+ The routine epic_exception shall be called by
+ exception vector at location 0x500, i.e.,
+ 603e core external exception vector.
+
+2. The host system is responsible for configuring
+ the MPC8240 including Embedded Utilities Memory
+ Block. All EPIC driver functions require the
+ content of Embedded Utilities Memory Block
+ Base Address Register, EUMBBAR, as the first
+ parameter.
+
+3. Before EPIC unit of MPC8240 can be used,
+ initialize EPIC unit by calling epicInit
+ with the corresponding parameters.
+
+ The initialization shall disable the 603e
+ core External Exception by calling CoreExtIntDisable( ).
+ Next, call epicInit( ). Last, enable the 603e core
+ External Exception by calling CoreExtIntEnable( ).
+
+4. After EPIC unit has been successfully initialized,
+ epicIntSourceSet( ) shall be used to register each
+ external interrupt source. Anytime, an external
+ interrupt source can be disabled or enabled by
+ calling corresponding function, epicIntDisable( ),
+ or epicIntEnable( ).
+
+ Global Timers' resource, base count and frequency,
+ can be changed by calling epicTmFrequencySet( )
+ and epicTmBaseSet( ).
+
+ To stop counting a specific global timer, use
+ the function, epicTmInhibit while epicTmEnable
+ can be used to start counting a timer.
+
+5. To mask a set of external interrupts that are
+ are certain level below, epicIntPrioritySet( )
+ can be used. For example, if the processor's
+ current task priority register is set to 0x7,
+ only interrupts of priority 0x8 or higher will
+ be passed to the processor.
+
+ Be careful when using this function. It may
+ corrupt the current interrupt pending, selector,
+ and request registers, resulting an invalid vetor.
+
+ After enabling an interrupt, disable it may also
+ cause an invalid vector. User may consider using
+ the spurious vector interrupt service routine to
+ handle this case.
+
+6. The EPIC driver routines contains a set
+ of utilities, Set and Get, for host system
+ to query and modify the desired EPIC source
+ registers.
+
+7. Each external interrupt source shall register
+ its interrupt service routine. The routine
+ shall contain all interrupt source specific
+ processes and keep as short as possible.
+
+ Special customized end of interrupt routine
+ is optional. If it is needed, it shall contain
+ the external interrupt source specific end of
+ interrupt process.
+
+ External interrupt exception vector at 0x500
+ shall always call the epicEOI just before
+ rfi instruction. Refer to the routine,
+ epic_exception, for a code sample.
+
+
diff --git a/cpu/mpc824x/drivers/epic/epic2.S b/cpu/mpc824x/drivers/epic/epic2.S
new file mode 100644
index 0000000..8979f88
--- /dev/null
+++ b/cpu/mpc824x/drivers/epic/epic2.S
@@ -0,0 +1,196 @@
+/**************************************
+ *
+ * copyright @ Motorola, 1999
+ *
+ **************************************/
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+#include <asm/processor.h>
+
+/*********************************************
+ * function: CoreExtIntEnable
+ *
+ * description: Enable 603e core external interrupt
+ *
+ * note: mtmsr is context-synchronization
+ **********************************************/
+ .text
+ .align 2
+ .global CoreExtIntEnable
+CoreExtIntEnable:
+ mfmsr r3
+
+ ori r3,r3,0x8000 /* enable external interrupt */
+ mtmsr r3
+
+ bclr 20, 0
+
+/*******************************************
+ * function: CoreExtIntDisable
+ *
+ * description: Disable 603e core external interrupt
+ *
+ * note:
+ *******************************************/
+ .text
+ .align 2
+ .global CoreExtIntDisable
+CoreExtIntDisable:
+ mfmsr r4
+
+ xor r3,r3,r3
+ or r3,r3,r4
+
+ andis. r4,r4,0xffff
+ andi. r3,r3,0x7fff /* disable external interrupt */
+
+ or r3,r3,r4
+ mtmsr r3
+
+ bclr 20, 0
+
+/*********************************************************
+ * function: epicEOI
+ *
+ * description: signal the EOI and restore machine status
+ * Input: r3 - value of eumbbar
+ * Output: r3 - value of eumbbar
+ * r4 - ISR vector value
+ * note:
+ ********************************************************/
+ .text
+ .align 2
+ .global epicEOI
+epicEOI:
+ lis r5,0x0006 /* Build End Of Interrupt Register offset */
+ ori r5,r5,0x00b0
+ xor r7,r7,r7 /* Clear r7 */
+ stwbrx r7,r5,r3 /* Save r7, writing to this register will
+ * intidate the end of processing the
+ * highest interrupt.
+ */
+ sync
+
+ /* ---RESTORE MACHINE STATE */
+ mfmsr r13 /* Clear Recoverable Interrupt bit in MSR */
+ or r7,r7,r13
+
+ andis. r7,r7,0xffff
+ andi. r13,r13,0x7ffd /* (and disable interrupts) */
+ or r13,r13,r7
+ mtmsr r13
+
+ lwz r13,0x1c(r1) /* pull ctr */
+ mtctr r13
+
+ lwz r13,0x18(r1) /* pull xer */
+ mtctr r13
+
+ lwz r13,0x14(r1) /* pull lr */
+ mtctr r13
+
+ lwz r13,0x10(r1) /* Pull SRR1 from stack */
+ mtspr SRR1,r13 /* Restore SRR1 */
+
+ lwz r13,0xc(r1) /* Pull SRR0 from stack */
+ mtspr SRR0,r13 /* Restore SRR0 */
+
+ lwz r13,0x8(r1) /* Pull User stack pointer from stack */
+ mtspr SPRG1,r13 /* Restore SPRG1 */
+
+ lwz r4,0x4(r1) /* vector value */
+ lwz r3,0x0(r1) /* eumbbar */
+ sync
+
+ addi r1,r1,0x20 /* Deallocate stack */
+ mtspr SPRG0,r1 /* Save updated Supervisor stack pointer */
+ mfspr r1,SPRG1 /* Restore User stack pointer */
+
+ bclr 20,0
+
+/***********************************************************
+ * function: exception routine called by exception vector
+ * at 0x500, external interrupt
+ *
+ * description: Kahlua EPIC controller
+ *
+ * input: r3 - content of eumbbar
+ * output: r3 - ISR return value
+ * r4 - Interrupt vector number
+ * note:
+ ***********************************************************/
+
+ .text
+ .align 2
+ .global epic_exception
+
+epic_exception:
+
+ /*---SAVE MACHINE STATE TO A STACK */
+ mtspr SPRG1,r1 /* Save User stack pointer to SPRG1 */
+ mfspr r1,SPRG0 /* Load Supervisor stack pointer into r1 */
+
+ stwu r3,-0x20(r1) /* Push the value of eumbbar onto stack */
+
+ mfspr r3,SPRG1 /* Push User stack pointer onto stack */
+ stw r3,0x8(r1)
+ mfspr r3,SRR0 /* Push SRR0 onto stack */
+ stw r1,0xc(r1)
+ mfspr r3,SRR1 /* Push SRR1 onto stack */
+ stw r3,0x10(r1)
+ mflr r3
+ stw r3,0x14(r1) /* Push LR */
+ mfxer r3
+ stw r3,0x18(r1) /* Push Xer */
+ mfctr r3
+ stw r3,0x1c(r1) /* Push CTR */
+
+ mtspr SPRG0,r1 /* Save updated Supervisor stack pointer
+ * value to SPRG0
+ */
+ mfmsr r3
+ ori r3,r3,0x0002 /* Set Recoverable Interrupt bit in MSR */
+ mtmsr r3
+
+ /* ---READ IN THE EUMBAR REGISTER */
+ lwz r6,0(r1) /* this is eumbbar */
+ sync
+
+ /* ---READ EPIC REGISTER: PROCESSOR INTERRUPT ACKNOWLEDGE REGISTER */
+ lis r5,0x0006 /* Build Interrupt Acknowledge Register
+ * offset
+ */
+ ori r5,r5,0x00a0
+ lwbrx r7,r5,r6 /* Load interrupt vector into r7 */
+ sync
+
+ /* --MASK OFF ALL BITS EXCEPT THE VECTOR */
+ xor r3,r3,r3
+ xor r4,r4,r4
+ or r3, r3, r6 /* eumbbar in r3 */
+ andi. r4,r7,0x00ff /* Mask off bits, vector in r4 */
+
+ stw r4,0x04(r1) /* save the vector value */
+
+ lis r5,epicISR@ha
+ ori r5,r5,epicISR@l
+ mtlr r5
+ blrl
+
+ xor r30,r30,r30
+ or r30,r30,r3 /* save the r3 which containts the return value from epicISR */
+
+ /* ---READ IN THE EUMBAR REGISTER */
+ lwz r3,0(r1)
+ sync
+
+ lis r5,epicEOI@ha
+ ori r5,r5,epicEOI@l
+ mtlr r5
+ blrl
+
+ xor r3,r3,r3
+ or r3,r3,r30 /* restore the ISR return value */
+
+ bclr 20,0
diff --git a/cpu/mpc824x/drivers/epic/epicutil.S b/cpu/mpc824x/drivers/epic/epicutil.S
new file mode 100644
index 0000000..a83fbd8
--- /dev/null
+++ b/cpu/mpc824x/drivers/epic/epicutil.S
@@ -0,0 +1,58 @@
+/**************************************
+ *
+ * copyright @ Motorola, 1999
+ *
+ *
+ * This file contains two commonly used
+ * lower level utility routines.
+ *
+ * The utility routines are also in other
+ * Kahlua device driver libraries. The
+ * need to be linked in only once.
+ **************************************/
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+
+/**********************************************************
+ * function: load_runtime_reg
+ *
+ * input: r3 - value of eumbbar
+ * r4 - register offset in embedded utility space
+ *
+ * output: r3 - register content
+ **********************************************************/
+ .text
+ .align 2
+ .global load_runtime_reg
+
+load_runtime_reg:
+
+ xor r5,r5,r5
+ or r5,r5,r3 /* save eumbbar */
+
+ lwbrx r3,r4,r5
+ sync
+
+ bclr 20, 0
+
+/****************************************************************
+ * function: store_runtime_reg
+ *
+ * input: r3 - value of eumbbar
+ * r4 - register offset in embedded utility space
+ * r5 - new value to be stored
+ *
+ ****************************************************************/
+ .text
+ .align 2
+ .global store_runtime_reg
+store_runtime_reg:
+
+ xor r0,r0,r0
+
+ stwbrx r5, r4, r3
+ sync
+
+ bclr 20,0
+