mimxrt/machine_uart: Set the UART clock to a fixed 40MHz value.

There is a single UART clock for all devices, so switching it for one will affect all devices used at that time. This commit fixes that issue by keeping the clock at a fixed value. This fixed clock still supports the common baud rates between 300 and 921600 baud. Signed-off-by: robert-hh <robert@hammelrath.com>
Infineon · Sep 29, 2023 · 0701341 · 0701341
1 parent 52e3da0
commit 0701341
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Showing 13 changed files with 12 additions and 25 deletions.
diff --git a/ports/mimxrt/boards/MIMXRT1011_clock_config.c b/ports/mimxrt/boards/MIMXRT1011_clock_config.c
@@ -241,7 +241,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart3);
     CLOCK_DisableClock(kCLOCK_Lpuart4);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable SPDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1011_clock_config.h b/ports/mimxrt/boards/MIMXRT1011_clock_config.h
@@ -71,7 +71,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT 30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT 0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT 117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY_CLK 0UL
 
 /*! @brief Usb1 PLL set for BOARD_BootClockRUN configuration.

diff --git a/ports/mimxrt/boards/MIMXRT1015_clock_config.c b/ports/mimxrt/boards/MIMXRT1015_clock_config.c
@@ -257,7 +257,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart3);
     CLOCK_DisableClock(kCLOCK_Lpuart4);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable SPDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1015_clock_config.h b/ports/mimxrt/boards/MIMXRT1015_clock_config.h
@@ -74,7 +74,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT            30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT          0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT             117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT              80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT              40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY1_CLK                0UL
 
 /*! @brief Usb1 PLL set for BOARD_BootClockRUN configuration.

diff --git a/ports/mimxrt/boards/MIMXRT1021_clock_config.c b/ports/mimxrt/boards/MIMXRT1021_clock_config.c
@@ -306,7 +306,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart7);
     CLOCK_DisableClock(kCLOCK_Lpuart8);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable SPDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1021_clock_config.h b/ports/mimxrt/boards/MIMXRT1021_clock_config.h
@@ -79,7 +79,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT 30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT 0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT 117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY1_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USDHC1_CLK_ROOT 176000000UL
 #define BOARD_BOOTCLOCKRUN_USDHC2_CLK_ROOT 176000000UL

diff --git a/ports/mimxrt/boards/MIMXRT1052_clock_config.c b/ports/mimxrt/boards/MIMXRT1052_clock_config.c
@@ -311,7 +311,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart7);
     CLOCK_DisableClock(kCLOCK_Lpuart8);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable LCDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1052_clock_config.h b/ports/mimxrt/boards/MIMXRT1052_clock_config.h
@@ -83,7 +83,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT 30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT 0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT 117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY1_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USBPHY2_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USDHC1_CLK_ROOT 198000000UL

diff --git a/ports/mimxrt/boards/MIMXRT1062_clock_config.c b/ports/mimxrt/boards/MIMXRT1062_clock_config.c
@@ -324,7 +324,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart7);
     CLOCK_DisableClock(kCLOCK_Lpuart8);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable LCDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1062_clock_config.h b/ports/mimxrt/boards/MIMXRT1062_clock_config.h
@@ -86,7 +86,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT 30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT 0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT 117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY1_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USBPHY2_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USDHC1_CLK_ROOT 198000000UL

diff --git a/ports/mimxrt/boards/MIMXRT1064_clock_config.c b/ports/mimxrt/boards/MIMXRT1064_clock_config.c
@@ -324,7 +324,7 @@ void BOARD_BootClockRUN(void) {
     CLOCK_DisableClock(kCLOCK_Lpuart7);
     CLOCK_DisableClock(kCLOCK_Lpuart8);
     /* Set UART_CLK_PODF. */
-    CLOCK_SetDiv(kCLOCK_UartDiv, 0);
+    CLOCK_SetDiv(kCLOCK_UartDiv, 1);
     /* Set Uart clock source. */
     CLOCK_SetMux(kCLOCK_UartMux, 0);
     /* Disable LCDIF clock gate. */

diff --git a/ports/mimxrt/boards/MIMXRT1064_clock_config.h b/ports/mimxrt/boards/MIMXRT1064_clock_config.h
@@ -86,7 +86,7 @@ void BOARD_InitBootClocks(void);
 #define BOARD_BOOTCLOCKRUN_SPDIF0_CLK_ROOT 30000000UL
 #define BOARD_BOOTCLOCKRUN_SPDIF0_EXTCLK_OUT 0UL
 #define BOARD_BOOTCLOCKRUN_TRACE_CLK_ROOT 117333333UL
-#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 80000000UL
+#define BOARD_BOOTCLOCKRUN_UART_CLK_ROOT 40000000UL
 #define BOARD_BOOTCLOCKRUN_USBPHY1_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USBPHY2_CLK 0UL
 #define BOARD_BOOTCLOCKRUN_USDHC1_CLK_ROOT 198000000UL

diff --git a/ports/mimxrt/machine_uart.c b/ports/mimxrt/machine_uart.c
@@ -153,24 +153,12 @@ static void machine_uart_ensure_active(machine_uart_obj_t *uart) {
     }
 }
 
-#if !defined(MIMXRT117x_SERIES)
-static inline void uart_set_clock_divider(uint32_t baudrate) {
-    // For baud rates < 460800 divide the clock by 10, supporting baud rates down to 50 baud.
-    if (baudrate >= 460800) {
-        CLOCK_SetDiv(kCLOCK_UartDiv, 0);
-    } else {
-        CLOCK_SetDiv(kCLOCK_UartDiv, 9);
-    }
-}
-#endif
-
 void machine_uart_set_baudrate(mp_obj_t uart_in, uint32_t baudrate) {
     machine_uart_obj_t *uart = MP_OBJ_TO_PTR(uart_in);
     #if defined(MIMXRT117x_SERIES)
     // Use the Lpuart1 clock value, which is set for All UART devices.
     LPUART_SetBaudRate(uart->lpuart, baudrate, CLOCK_GetRootClockFreq(kCLOCK_Root_Lpuart1));
     #else
-    uart_set_clock_divider(baudrate);
     LPUART_SetBaudRate(uart->lpuart, baudrate, CLOCK_GetClockRootFreq(kCLOCK_UartClkRoot));
     #endif
 }
@@ -315,7 +303,6 @@ STATIC mp_obj_t machine_uart_init_helper(machine_uart_obj_t *self, size_t n_args
         // Use the Lpuart1 clock value, which is set for All UART devices.
         LPUART_Init(self->lpuart, &self->config, CLOCK_GetRootClockFreq(kCLOCK_Root_Lpuart1));
         #else
-        uart_set_clock_divider(self->config.baudRate_Bps);
         LPUART_Init(self->lpuart, &self->config, CLOCK_GetClockRootFreq(kCLOCK_UartClkRoot));
         #endif
         LPUART_TransferCreateHandle(self->lpuart, &self->handle,  LPUART_UserCallback, self);