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Revert "RISC-V: Add RV32E / FPU support for GCC (#140)" (#163)
This reverts commit 0037a6c.
1 parent cfb51b3 commit 2f14899

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‎portable/GCC/RISC-V/port.c‎

Lines changed: 46 additions & 91 deletions
Original file line numberDiff line numberDiff line change
@@ -25,11 +25,9 @@
2525
* 1 tab == 4 spaces!
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*/
2727

28-
/* ------------------------------------------------------------------
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* This file is part of the FreeRTOS distribution and was contributed
30-
* to the project by SiFive
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* ------------------------------------------------------------------
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*/
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/*-----------------------------------------------------------
29+
* Implementation of functions defined in portable.h for the RISC-V RV32 port.
30+
*----------------------------------------------------------*/
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3432
/* Scheduler includes. */
3533
#include "FreeRTOS.h"
@@ -120,69 +118,31 @@ task stack, not the ISR stack). */
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121119
#if( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 )
122120

123-
#if( __riscv_xlen == 32 )
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void vPortSetupTimerInterrupt( void )
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{
126-
uint32_t ulCurrentTimeHigh, ulCurrentTimeLow;
127-
volatile uint32_t * const pulTimeHigh = ( volatile uint32_t * const ) ( ( configMTIME_BASE_ADDRESS ) + 4UL ); /* 8-byte typer so high 32-bit word is 4 bytes up. */
128-
volatile uint32_t * const pulTimeLow = ( volatile uint32_t * const ) ( configMTIME_BASE_ADDRESS );
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volatile uint32_t * pulTimeCompareRegisterHigh;
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volatile uint32_t * pulTimeCompareRegisterLow;
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volatile uint32_t ulHartId;
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__asm volatile ( "csrr %0, mhartid" : "=r" ( ulHartId ) );
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/* pullMachineTimerCompareRegister is used by freertos_risc_v_trap_handler */
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pullMachineTimerCompareRegister = ( volatile uint64_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) );
138-
pulTimeCompareRegisterLow = ( volatile uint32_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) );
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pulTimeCompareRegisterHigh = ( volatile uint32_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) + 4UL );
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do
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{
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ulCurrentTimeHigh = *pulTimeHigh;
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ulCurrentTimeLow = *pulTimeLow;
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} while( ulCurrentTimeHigh != *pulTimeHigh );
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ullNextTime = ( uint64_t ) ulCurrentTimeHigh;
148-
ullNextTime <<= 32ULL; /* High 4-byte word is 32-bits up. */
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ullNextTime |= (( uint64_t ) ulCurrentTimeLow );
150-
ullNextTime += (( uint64_t ) uxTimerIncrementsForOneTick );
151-
/* Per spec, the RISC-V MTIME/MTIMECMP registers are 64 bit,
152-
* and are NOT internally latched for multiword transfers.
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* Need to be careful about sequencing to avoid triggering
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* spurious interrupts: For that set the high word to a max
155-
* value first.
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*/
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*pulTimeCompareRegisterHigh = 0xFFFFFFFF;
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*pulTimeCompareRegisterLow = (uint32_t)( ullNextTime );
159-
*pulTimeCompareRegisterHigh = (uint32_t)( ullNextTime >> 32ULL );
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/* Prepare the time to use after the next tick interrupt. */
162-
ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick;
163-
}
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#endif /* __riscv_xlen == 32 */
165-
166-
#if( __riscv_xlen == 64 )
167-
void vPortSetupTimerInterrupt( void )
168-
{
169-
volatile uint32_t * const pulTime = ( volatile uint32_t * const ) ( configMTIME_BASE_ADDRESS );
170-
171-
volatile uint32_t ulHartId;
172-
173-
__asm volatile ( "csrr %0, mhartid" : "=r" ( ulHartId ) );
174-
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pullMachineTimerCompareRegister = ( volatile uint64_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) );
176-
177-
ullNextTime = *pulTime;
178-
179-
ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick;
180-
*pullMachineTimerCompareRegister = ullNextTime;
181-
182-
/* Prepare the time to use after the next tick interrupt. */
183-
ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick;
184-
}
185-
#endif /* __riscv_xlen == 64 */
121+
void vPortSetupTimerInterrupt( void )
122+
{
123+
uint32_t ulCurrentTimeHigh, ulCurrentTimeLow;
124+
volatile uint32_t * const pulTimeHigh = ( volatile uint32_t * const ) ( ( configMTIME_BASE_ADDRESS ) + 4UL ); /* 8-byte typer so high 32-bit word is 4 bytes up. */
125+
volatile uint32_t * const pulTimeLow = ( volatile uint32_t * const ) ( configMTIME_BASE_ADDRESS );
126+
volatile uint32_t ulHartId;
127+
128+
__asm volatile( "csrr %0, mhartid" : "=r"( ulHartId ) );
129+
pullMachineTimerCompareRegister = ( volatile uint64_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) );
130+
131+
do
132+
{
133+
ulCurrentTimeHigh = *pulTimeHigh;
134+
ulCurrentTimeLow = *pulTimeLow;
135+
} while( ulCurrentTimeHigh != *pulTimeHigh );
136+
137+
ullNextTime = ( uint64_t ) ulCurrentTimeHigh;
138+
ullNextTime <<= 32ULL; /* High 4-byte word is 32-bits up. */
139+
ullNextTime |= ( uint64_t ) ulCurrentTimeLow;
140+
ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick;
141+
*pullMachineTimerCompareRegister = ullNextTime;
142+
143+
/* Prepare the time to use after the next tick interrupt. */
144+
ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick;
145+
}
186146

187147
#endif /* ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIME_BASE_ADDRESS != 0 ) */
188148
/*-----------------------------------------------------------*/
@@ -218,7 +178,20 @@ extern void xPortStartFirstTask( void );
218178
configure whichever clock is to be used to generate the tick interrupt. */
219179
vPortSetupTimerInterrupt();
220180

221-
/* Enabling mtime and external interrupts will be made into xPortStartFirstTask function */
181+
#if( ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) )
182+
{
183+
/* Enable mtime and external interrupts. 1<<7 for timer interrupt, 1<<11
184+
for external interrupt. _RB_ What happens here when mtime is not present as
185+
with pulpino? */
186+
__asm volatile( "csrs mie, %0" :: "r"(0x880) );
187+
}
188+
#else
189+
{
190+
/* Enable external interrupts. */
191+
__asm volatile( "csrs mie, %0" :: "r"(0x800) );
192+
}
193+
#endif /* ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) */
194+
222195
xPortStartFirstTask();
223196

224197
/* Should not get here as after calling xPortStartFirstTask() only tasks
@@ -232,26 +205,8 @@ void vPortEndScheduler( void )
232205
/* Not implemented. */
233206
for( ;; );
234207
}
235-
/*-----------------------------------------------------------*/
236208

237-
#if( configENABLE_FPU == 1 )
238-
void vPortSetupFPU( void )
239-
{
240-
#ifdef __riscv_fdiv
241-
__asm__ __volatile__ (
242-
"csrr t0, misa \n" /* Get misa */
243-
"li t1, 0x10028 \n" /* 0x10028 = Q,F,D Quad, Single or Double precission floating point */
244-
"and t0, t0, t1 \n"
245-
"beqz t0, 1f \n" /* check if Q,F or D is present into misa */
246-
"csrr t0, mstatus \n" /* Floating point unit is present so need to put it into initial state */
247-
"lui t1, 0x2 \n" /* t1 = 0x1 << 12 */
248-
"or t0, t0, t1 \n"
249-
"csrw mstatus, t0 \n" /* Set FS to initial state */
250-
"csrwi fcsr, 0 \n" /* Clear Floating-point Control and Status Register */
251-
"1: \n"
252-
:::
253-
);
254-
#endif /* __riscv_fdiv */
255-
}
256-
#endif /* configENABLE_FPU */
257-
/*-----------------------------------------------------------*/
209+
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