From e21ec5162adafcced2de3abef60e7b942e7874af Mon Sep 17 00:00:00 2001
From: Roberto Hexsel <roberto@inf.ufpr.br>
Date: Fri, 22 Apr 2016 11:23:02 -0300
Subject: [PATCH] hw interrupts were connected to the wront IRQs
---
cMIPS/include/handlers.s | 37 ++++++++++++++++++++++---------------
cMIPS/include/start.s | 6 +++---
cMIPS/tests/extCounter.c | 2 +-
cMIPS/vhdl/tb_cMIPS.vhd | 6 ++++--
4 files changed, 30 insertions(+), 21 deletions(-)
diff --git a/cMIPS/include/handlers.s b/cMIPS/include/handlers.s
index 01fadb9..1889009 100644
--- a/cMIPS/include/handlers.s
+++ b/cMIPS/include/handlers.s
@@ -31,7 +31,7 @@ extCounter:
sw $zero, 0($k0) # Reset counter, remove interrupt request
#----------------------------------
- # save additional registers
+ # if you change this handler, then save additional registers
# lui $k1, %hi(_counter_saves)
# ori $k1, $k1, %lo(_counter_saves)
# sw $a0, 0*4($k1)
@@ -50,7 +50,7 @@ extCounter:
sw $k1,0($k0)
#----------------------------------
- # and then restore those same registers
+ # if you changed this handler, then restore those same registers
# lui $k1, %hi(_counter_saves)
# ori $k1, $k1, %lo(_counter_saves)
# lw $a0, 0*4($k1)
@@ -206,11 +206,14 @@ cmips_delay:
#----------------------------------------------------------------
- # print a message, does not disturbs registers
- .bss
+ # print a message from within "the kernel"
+ # void cmips_kmsg( $k1 )
+ # this function preserves registers other than k0,k1
+ #
+ .data
.align 2
- .comm _kmsg_saves 4*4 # area to save up to 4 registers
- # _kmsg_saves[0]=$a0, [1]=$a1, [2]=$a2, [3]=$ra
+ .comm _kmsg_saves 4*4 # area to save 4 registers
+ # _kmsg_saves[0]=$a0, [1]=$a1, [2]=$a2, [3]=$a3
#
.text
.align 2
@@ -218,8 +221,8 @@ cmips_delay:
.set noat
.global cmips_kmsg
.ent cmips_kmsg
- .equ stdout_addr,(x_IO_BASE_ADDR + 1*x_IO_ADDR_RANGE);
- # void cmips_kmsg( $k1 )
+ .equ stdout,(x_IO_BASE_ADDR + 1*x_IO_ADDR_RANGE);
+
cmips_kmsg:
lui $k0, %hi(_kmsg_saves)
ori $k0, $k0, %lo(_kmsg_saves)
@@ -232,14 +235,15 @@ cmips_kmsg:
sll $k1, $k1, 2 # adjust index onto table
addu $a1, $a1, $k1
-
- lui $a2, %hi(stdout_addr)
- ori $a2, $a2, %lo(stdout_addr)
+ lw $a1, 0($a1) # de-reference pointer
+
+ lui $a2, %hi(stdout)
+ ori $a2, $a2, %lo(stdout)
k_for: lbu $a0, 0($a1)
- sb $a0, 0($a2) # send it to simulator's stdout
- bne $a0, $zero, k_for
addiu $a1, $a1, 1
+ bne $a0, $zero, k_for
+ sb $a0, 0($a2) # send it to simulator's stdout
lw $a0, 0*4($k0)
lw $a1, 1*4($k0)
@@ -250,12 +254,15 @@ k_for: lbu $a0, 0($a1)
.equ kmsg_interr,0
.equ kmsg_excep,1
+
.data
.align 2
- .global _kmsg_list
_kmsg_interr: .asciiz "\n\tinterrupt\n\n"
-_kmsg_excep: .asciiz "\n\texceptioninterrupt\n\n"
+_kmsg_excep: .asciiz "\n\texception\n\n"
+ .global _kmsg_list
+ .data
+ .align 2
_kmsg_list: .word _kmsg_interr,_kmsg_excep
#----------------------------------------------------------------
diff --git a/cMIPS/include/start.s b/cMIPS/include/start.s
index 7aad3ea..f32602b 100644
--- a/cMIPS/include/start.s
+++ b/cMIPS/include/start.s
@@ -130,7 +130,7 @@ _excp_0100:
.set noreorder
.set noat
- la $k0, x_IO_BASE_ADDR
+ la $k0, x_IO_BASE_ADDR # PANIC: SHOULD NEVER GET HERE
mfc0 $k1, cop0_CAUSE
sw $k1, 0($k0) # print CAUSE, flush pipe and stop simulation
nop
@@ -268,7 +268,7 @@ _excp_0200:
mfc0 $k1, cop0_STATUS
and $k0, $k0, $k1 # and mask with IM bits
- srl $k0, $k0, 11 # keep only 3 MS bits of IP (irq7..5)
+ srl $k0, $k0, 10 # keep only 3 MS bits of IP (irq7..5)
lui $k1, %hi(handlers_tbl) # plus displacement in j-table of 8 bytes
ori $k1, $k1, %lo(handlers_tbl)
add $k1, $k1, $k0
@@ -326,7 +326,7 @@ _excp_BFC0:
.set noreorder
.set noat
- la $k0, x_IO_BASE_ADDR
+ la $k0, x_IO_BASE_ADDR # PANIC: SHOULD NEVER GET HERE
mfc0 $k1, cop0_CAUSE
sw $k1, 0($k0) # print CAUSE, flush pipe and stop simulation
nop
diff --git a/cMIPS/tests/extCounter.c b/cMIPS/tests/extCounter.c
index 75a0b62..4fc8f16 100644
--- a/cMIPS/tests/extCounter.c
+++ b/cMIPS/tests/extCounter.c
@@ -34,7 +34,7 @@ void main(void) {
increased = FALSE;
}
- } while ( (readCounter() & 0x3fffffff) < (newValue & 0x3ffffff) );
+ } while ( (readCounter() & 0x3fffffff) < (newValue & 0x3fffffff) );
// are we done yet?
if (increased) {
diff --git a/cMIPS/vhdl/tb_cMIPS.vhd b/cMIPS/vhdl/tb_cMIPS.vhd
index 135e1fe..40335d2 100644
--- a/cMIPS/vhdl/tb_cMIPS.vhd
+++ b/cMIPS/vhdl/tb_cMIPS.vhd
@@ -506,9 +506,11 @@ begin -- TB
not_waiting <= (inst_wait and data_wait and sdram_wait); -- and io_wait);
+ -- Count=Compare at IRQ7, UART at IRQ6, extCounter at IRQ5
+ -- C=C U E 0 0 0 sw1 sw0
+ irq <= '0' & uart_irq & counter_irq & b"000"; -- uart+counter interrupts
+ -- irq <= b"00" & counter_irq & b"000"; -- counter interrupts
-- irq <= b"000000"; -- NO interrupt requests
- irq <= uart_irq & counter_irq & b"0000"; -- uart+counter interrupts
- -- irq <= counter_irq & b"00000"; -- counter interrupts
nmi <= '0'; -- input port to TB
U_CORE: core
--
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