anlogic: fix high frequency flash programming issue

src/anlogic.cpp

@@ -29,7 +29,7 @@ Anlogic::Anlogic(Jtag *jtag, const std::string &filename,
 	const std::string &file_type,
 	Device::prog_type_t prg_type, bool verify, int8_t verbose):
 	Device(jtag, filename, file_type, verify, verbose),
-	SPIInterface(filename, verbose, 0, verify)
+	SPIInterface(filename, verbose, 0, verify), _target_freq(0)
 {
 	if (prg_type == Device::RD_FLASH) {
 		_mode = Device::READ_MODE;
@@ -157,6 +157,11 @@ uint32_t Anlogic::idCode()
 
 bool Anlogic::prepare_flash_access()
 {
+	_target_freq = _jtag->getClkFreq();
+	if (_target_freq > 6000000) {
+		_jtag->setClkFreq(6000000);
+	}
+
 	for (int i = 0; i < 5; i++)
 		_jtag->shiftIR(BYPASS, IRLENGTH);
 	//Verify Device id.
@@ -174,6 +179,13 @@ bool Anlogic::prepare_flash_access()
 	return true;
 }
 
+void Anlogic::restore_flash_access_frequency()
+{
+	if (_target_freq > 6000000) {
+		_jtag->setClkFreq(_target_freq);
+	}
+}
+
 /* SPI wrapper
  * For read operation a delay of one bit is added
  * So add one bit more and move everything by one

src/anlogic.hpp

@@ -68,11 +68,18 @@ class Anlogic: public Device, SPIInterface {
 		 * \brief move device to SPI access
 		 */
 		virtual bool prepare_flash_access() override;
+		/*!
+		 * \brief restore frequency after flash ID read
+		 */
+		virtual void restore_flash_access_frequency() override;
 		/*!
 		 * \brief end of device to SPI access
 		 */
 		virtual bool post_flash_access() override {reset(); return true;}
 
+private:
+		uint32_t _target_freq; /*< target JTAG frequency */
+
 };
 
 #endif  // SRC_ANLOGIC_HPP_

src/spiInterface.cpp

@@ -187,6 +187,7 @@ bool SPIInterface::write(uint32_t offset, const uint8_t *data, uint32_t len,
 	/* test SPI */
 	try {
 		SPIFlash flash(this, unprotect_flash, _spif_verbose);
+		restore_flash_access_frequency();
 		flash.read_status_reg();
 		if (flash.erase_and_prog(offset, data, len) == -1)
 			ret = false;

src/spiInterface.hpp

@@ -108,6 +108,10 @@ class SPIInterface {
 	 * \brief prepare SPI flash access
 	 */
 	virtual bool prepare_flash_access() {return false;}
+	/*!
+	 * \brief restore frequency after flash ID read
+	 */
+	virtual void restore_flash_access_frequency() {}
 	/*!
 	 * \brief end of SPI flash access
 	 */