cpu/gowin_emcu: Switch to LiteX's UART (Using integrated UART is not …

…really useful for now and make things less flexible, ie no UARTBone/Crossover possibilities).
enjoy-digital · Jan 4, 2024 · 6c6c238 · 6c6c238
1 parent 6a68370
commit 6c6c238
Show file tree

Hide file tree

Showing 4 changed files with 2 additions and 91 deletions.
diff --git a/litex/soc/cores/cpu/gowin_emcu/core.py b/litex/soc/cores/cpu/gowin_emcu/core.py
@@ -47,7 +47,6 @@ def mem_map(self):
     def gcc_flags(self):
         flags =  f" -march=armv7-m -mthumb"
         flags += f" -D__CortexM3__"
-        flags += f" -DUART_POLLING"
         return flags
 
     def __init__(self, platform, variant="standard"):
@@ -64,8 +63,8 @@ def __init__(self, platform, variant="standard"):
         self.cpu_params = dict(
             # Clk/Rst.
             i_FCLK           = ClockSignal("sys"),
-            i_PORESETN       = ~ (ResetSignal("sys") | self.reset),
-            i_SYSRESETN      = ~ (ResetSignal("sys") | self.reset),
+            i_PORESETN       = ~(ResetSignal("sys") | self.reset),
+            i_SYSRESETN      = ~(ResetSignal("sys") | self.reset),
             i_MTXREMAP       = Signal(4, reset=0b1111),
             o_MTXHRESETN     = bus_reset_n,
 

diff --git a/litex/soc/cores/cpu/gowin_emcu/crt0.c b/litex/soc/cores/cpu/gowin_emcu/crt0.c
@@ -19,9 +19,6 @@ void _start(void) {
     for (uint32_t *x = &_fbss; x < &_ebss; x ++)
         *x = 0;
 
-    UART0->ctrl = 0b11; // set rx and tx enable bits
-    UART0->baud_div = CONFIG_CLOCK_FREQUENCY / 115200; // FIXME
-
     __asm__("bl main");
     while(1);
 }

diff --git a/litex/soc/cores/cpu/gowin_emcu/irq.h b/litex/soc/cores/cpu/gowin_emcu/irq.h
@@ -1,37 +1,4 @@
 #ifndef __IRQ_H
 #define __IRQ_H
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-static inline unsigned int irq_getie(void)
-{
-	return 0; /* FIXME */
-}
-
-static inline void irq_setie(unsigned int ie)
-{
-	/* FIXME */
-}
-
-static inline unsigned int irq_getmask(void)
-{
-	return 0; /* FIXME */
-}
-
-static inline void irq_setmask(unsigned int mask)
-{
-	/* FIXME */
-}
-
-static inline unsigned int irq_pending(void)
-{
-	return 0; /* FIXME */
-}
-
-#ifdef __cplusplus
-}
-#endif
-
 #endif /* __IRQ_H */
diff --git a/litex/soc/cores/cpu/gowin_emcu/system.h b/litex/soc/cores/cpu/gowin_emcu/system.h
@@ -12,58 +12,6 @@ void flush_l2_cache(void);
 void busy_wait(unsigned int ms);
 void busy_wait_us(unsigned int us);
 
-#include <stdint.h>
-
-// FIXME
-#define CSR_UART_BASE
-
-struct EMCU_UART
-{
-  volatile uint32_t data;
-  volatile uint32_t state;
-  volatile uint32_t ctrl;
-  volatile uint32_t int_ctrl;
-  volatile uint32_t baud_div;
-};
-
-#define PERIPHERALS_BASE 0x40000000
-#define UART0 ((struct EMCU_UART *) (PERIPHERALS_BASE + 0x4000))
-
-static inline char uart_txfull_read(void);
-static inline char uart_rxempty_read(void);
-static inline void uart_ev_enable_write(char c);
-static inline void uart_rxtx_write(char c);
-static inline char uart_rxtx_read(void);
-static inline void uart_ev_pending_write(char);
-static inline char uart_ev_pending_read(void);
-
-static inline char uart_txfull_read(void) {
-  return UART0->state & 0b01;
-}
-
-static inline char uart_rxempty_read(void) {
-  return !(UART0->state & 0b10);
-}
-
-static inline void uart_ev_enable_write(char c) {
-  // FIXME
-}
-
-static inline void uart_rxtx_write(char c) {
-  UART0->data = (uint32_t) c;
-}
-
-static inline char uart_rxtx_read(void)
-{
-  return (char)(UART0->data);
-}
-
-static inline void uart_ev_pending_write(char x) {}
-static inline char uart_ev_pending_read(void) {
-  return 0;
-}
-
-
 #ifdef __cplusplus
 }
 #endif