h1r9: use timer to detect external clock frequency

firmware/common/clkin.c

@@ -0,0 +1,114 @@
+/*
+ * Copyright 2022 Great Scott Gadgets
+ *
+ * This file is part of HackRF.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "gpdma.h"
+#include <libopencm3/lpc43xx/timer.h>
+#include <libopencm3/lpc43xx/scu.h>
+#include <libopencm3/lpc43xx/gima.h>
+#include <stdint.h>
+
+#define CLOCK_CYCLES_1_MS     (204000)
+#define MEASUREMENT_WINDOW_MS (50)
+#define MEASUREMENT_CYCLES    (CLOCK_CYCLES_1_MS * MEASUREMENT_WINDOW_MS)
+
+/* DMA linked list item */
+typedef struct {
+	uint32_t src;
+	uint32_t dest;
+	uint32_t next_lli;
+	uint32_t control;
+} dma_lli;
+
+/* timer control register configuration sequence */
+typedef struct {
+	uint32_t first_tcr;
+	uint32_t second_tcr;
+} tcr_sequence;
+
+dma_lli timer_dma_lli;
+tcr_sequence reset;
+
+void clkin_detect_init(void)
+{
+	/* Timer3 triggers periodic measurement */
+	timer_set_prescaler(TIMER3, 0);
+	timer_set_mode(TIMER3, TIMER_CTCR_MODE_TIMER);
+	TIMER3_MCR = TIMER_MCR_MR0R;
+	TIMER3_EMR = TIMER_EMR_EM0 | TIMER_EMR_EM3 |
+		(TIMER_EMR_EMC_SET << TIMER_EMR_EMC0_SHIFT) |
+		(TIMER_EMR_EMC_TOGGLE << TIMER_EMR_EMC3_SHIFT);
+	TIMER3_MR3 = MEASUREMENT_CYCLES;
+	TIMER3_MR0 = MEASUREMENT_CYCLES;
+
+	/* Timer0 counts CLKIN */
+	timer_set_prescaler(TIMER0, 0);
+	TIMER0_CCR = TIMER_CCR_CAP3RE;
+	GIMA_CAP0_3_IN = 0x20; // T3_MAT3
+
+	/* measure CLKIN signal on P2_5, pin 91, CTIN_2 */
+	TIMER0_CTCR = TIMER_CTCR_MODE_COUNTER_RISING | TIMER_CTCR_CINSEL_CAPN_2;
+	scu_pinmux(P2_5, SCU_GPIO_PDN | SCU_CONF_FUNCTION1);
+	GIMA_CAP0_2_IN = 0x00; // CTIN_2
+
+	// temporarily testing with T0_CAP1, P1_12, pin 56, P28 pin 4
+	//TIMER0_CTCR = TIMER_CTCR_MODE_COUNTER_RISING | TIMER_CTCR_CINSEL_CAPN_1;
+	//scu_pinmux(P1_12, SCU_GPIO_PDN | SCU_CONF_FUNCTION4);
+	//GIMA_CAP0_1_IN = 0x20; // T0_CAP1
+
+	reset.first_tcr = TIMER_TCR_CEN | TIMER_TCR_CRST;
+	reset.second_tcr = TIMER_TCR_CEN;
+	timer_dma_lli.src = (uint32_t) & (reset);
+	timer_dma_lli.dest = (uint32_t) & (TIMER0_TCR);
+	timer_dma_lli.next_lli = (uint32_t) & (timer_dma_lli);
+	timer_dma_lli.control = GPDMA_CCONTROL_TRANSFERSIZE(2) |
+		GPDMA_CCONTROL_SBSIZE(0)   // 1
+		| GPDMA_CCONTROL_DBSIZE(0) // 1
+		| GPDMA_CCONTROL_SWIDTH(2) // 32-bit word
+		| GPDMA_CCONTROL_DWIDTH(2) // 32-bit word
+		| GPDMA_CCONTROL_S(0)      // AHB Master 0
+		| GPDMA_CCONTROL_D(1)      // AHB Master 1
+		| GPDMA_CCONTROL_SI(1)     // increment source
+		| GPDMA_CCONTROL_DI(0)     // do not increment destination
+		| GPDMA_CCONTROL_PROT1(0)  // user mode
+		| GPDMA_CCONTROL_PROT2(0)  // not bufferable
+		| GPDMA_CCONTROL_PROT3(0)  // not cacheable
+		| GPDMA_CCONTROL_I(0);     // interrupt disabled
+	gpdma_controller_enable();
+	GPDMA_C0SRCADDR = timer_dma_lli.src;
+	GPDMA_C0DESTADDR = timer_dma_lli.dest;
+	GPDMA_C0LLI = timer_dma_lli.next_lli;
+	GPDMA_C0CONTROL = timer_dma_lli.control;
+	GPDMA_C0CONFIG = GPDMA_CCONFIG_DESTPERIPHERAL(0x7) // T3_MAT0
+		| GPDMA_CCONFIG_FLOWCNTRL(1)               // memory-to-peripheral
+		| GPDMA_CCONFIG_H(0);                      // do not halt
+	gpdma_channel_enable(0);
+
+	/* start counting */
+	timer_reset(TIMER0);
+	timer_reset(TIMER3);
+	timer_enable_counter(TIMER0);
+	timer_enable_counter(TIMER3);
+}
+
+uint32_t clkin_frequency(void)
+{
+	return TIMER0_CR3 * (1000 / MEASUREMENT_WINDOW_MS);
+};

firmware/common/clkin.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2022 Great Scott Gadgets
+ *
+ * This file is part of HackRF.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __CLKIN_H__
+#define __CLKIN_H__
+
+#include <stdint.h>
+
+void clkin_detect_init(void);
+uint32_t clkin_frequency(void);
+
+#endif //__CLKIN_H__

firmware/common/hackrf_core.c

@@ -727,7 +727,7 @@ void cpu_clock_init(void)
 	CCU1_CLK_APB3_ADC1_CFG = 0;
 	CCU1_CLK_APB3_CAN0_CFG = 0;
 	CCU1_CLK_APB3_DAC_CFG = 0;
-	CCU1_CLK_M4_DMA_CFG = 0;
+	//CCU1_CLK_M4_DMA_CFG = 0;
 	CCU1_CLK_M4_EMC_CFG = 0;
 	CCU1_CLK_M4_EMCDIV_CFG = 0;
 	CCU1_CLK_M4_ETHERNET_CFG = 0;
@@ -737,10 +737,10 @@ void cpu_clock_init(void)
 	// CCU1_CLK_M4_SCT_CFG = 0;
 	CCU1_CLK_M4_SDIO_CFG = 0;
 	CCU1_CLK_M4_SPIFI_CFG = 0;
-	CCU1_CLK_M4_TIMER0_CFG = 0;
+	//CCU1_CLK_M4_TIMER0_CFG = 0;
 	CCU1_CLK_M4_TIMER1_CFG = 0;
 	CCU1_CLK_M4_TIMER2_CFG = 0;
-	CCU1_CLK_M4_TIMER3_CFG = 0;
+	//CCU1_CLK_M4_TIMER3_CFG = 0;
 	CCU1_CLK_M4_UART1_CFG = 0;
 	CCU1_CLK_M4_USART0_CFG = 0;
 	CCU1_CLK_M4_USART2_CFG = 0;

firmware/hackrf-common.cmake

@@ -185,6 +185,8 @@ macro(DeclareTargets)
 		${PATH_HACKRF_FIRMWARE_COMMON}/hackrf_ui.c
 		${PATH_HACKRF_FIRMWARE_COMMON}/platform_detect.c
 		${PATH_HACKRF_FIRMWARE_COMMON}/firmware_info.c
+		${PATH_HACKRF_FIRMWARE_COMMON}/clkin.c
+		${PATH_HACKRF_FIRMWARE_COMMON}/gpdma.c
 	)
 
 	if(BOARD STREQUAL "RAD1O")

firmware/hackrf_usb/hackrf_usb.c

@@ -27,6 +27,7 @@
 #include <libopencm3/lpc43xx/ipc.h>
 #include <libopencm3/lpc43xx/m4/nvic.h>
 #include <libopencm3/lpc43xx/rgu.h>
+#include <libopencm3/lpc43xx/timer.h>
 
 #include <streaming.h>
 
@@ -55,6 +56,7 @@
 #include "portapack.h"
 #include "hackrf_ui.h"
 #include "platform_detect.h"
+#include "clkin.h"
 
 extern uint32_t __m0_start__;
 extern uint32_t __m0_end__;
@@ -286,6 +288,8 @@ int main(void)
 	}
 	operacake_init(operacake_allow_gpio);
 
+	clkin_detect_init();
+
 	while (true) {
 		transceiver_request_t request;