Prepare flash code for multiple device type support (#5683)

* Prepare flash drivers for multiple device type support

* Add static assertions on device page and flashfs alloc sizes.

src/main/drivers/flash.c

@@ -0,0 +1,153 @@
+/*
+ * This file is part of Betaflight/Cleanflight.
+ *
+ * Betaflight/Cleanflight 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 3 of
+ * the License, or (at your option) any later version.
+ *
+ * Betaflight/Cleanflight 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 Betaflight/Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "platform.h"
+
+#include "build/debug.h"
+
+#ifdef USE_FLASH
+
+#include "flash.h"
+#include "flash_impl.h"
+#include "flash_m25p16.h"
+#include "drivers/bus_spi.h"
+#include "drivers/io.h"
+#include "drivers/time.h"
+
+static busDevice_t busInstance;
+static busDevice_t *busdev;
+
+static flashDevice_t flashDevice;
+
+// Read chip identification and send it to device detect
+
+bool flashInit(const flashConfig_t *flashConfig)
+{
+    busdev = &busInstance;
+    busdev->bustype = BUSTYPE_SPI;
+    spiBusSetInstance(busdev, spiInstanceByDevice(SPI_CFG_TO_DEV(flashConfig->spiDevice)));
+    if (flashConfig->csTag) {
+        busdev->busdev_u.spi.csnPin = IOGetByTag(flashConfig->csTag);
+    } else {
+        return false;
+    }
+
+    IOInit(busdev->busdev_u.spi.csnPin, OWNER_FLASH_CS, 0);
+    IOConfigGPIO(busdev->busdev_u.spi.csnPin, SPI_IO_CS_CFG);
+    IOHi(busdev->busdev_u.spi.csnPin);
+
+#ifndef M25P16_SPI_SHARED
+    //Maximum speed for standard READ command is 20mHz, other commands tolerate 25mHz
+    //spiSetDivisor(busdev->busdev_u.spi.instance, SPI_CLOCK_FAST);
+    spiSetDivisor(busdev->busdev_u.spi.instance, SPI_CLOCK_STANDARD*2);
+#endif
+
+    flashDevice.busdev = busdev;
+
+    const uint8_t out[] = { SPIFLASH_INSTRUCTION_RDID, 0, 0, 0 };
+
+    delay(50); // short delay required after initialisation of SPI device instance.
+
+    /* Just in case transfer fails and writes nothing, so we don't try to verify the ID against random garbage
+     * from the stack:
+     */
+    uint8_t in[4];
+    in[1] = 0;
+
+    // Clearing the CS bit terminates the command early so we don't have to read the chip UID:
+    spiBusTransfer(busdev, out, in, sizeof(out));
+
+    // Manufacturer, memory type, and capacity
+    uint32_t chipID = (in[1] << 16) | (in[2] << 8) | (in[3]);
+
+#ifdef USE_FLASH_M25P16
+    if (m25p16_detect(&flashDevice, chipID)) {
+        return true;
+    }
+#endif
+
+    spiPreInitCs(flashConfig->csTag);
+
+    return false;
+}
+
+bool flashIsReady(void)
+{
+    return flashDevice.vTable->isReady(&flashDevice);
+}
+
+bool flashWaitForReady(uint32_t timeoutMillis)
+{
+    return flashDevice.vTable->waitForReady(&flashDevice, timeoutMillis);
+}
+
+void flashEraseSector(uint32_t address)
+{
+    flashDevice.vTable->eraseSector(&flashDevice, address);
+}
+
+void flashEraseCompletely(void)
+{
+    flashDevice.vTable->eraseCompletely(&flashDevice);
+}
+
+void flashPageProgramBegin(uint32_t address)
+{
+    flashDevice.vTable->pageProgramBegin(&flashDevice, address);
+}
+
+void flashPageProgramContinue(const uint8_t *data, int length)
+{
+    flashDevice.vTable->pageProgramContinue(&flashDevice, data, length);
+}
+
+void flashPageProgramFinish(void)
+{
+    flashDevice.vTable->pageProgramFinish(&flashDevice);
+}
+
+void flashPageProgram(uint32_t address, const uint8_t *data, int length)
+{
+    flashDevice.vTable->pageProgram(&flashDevice, address, data, length);
+}
+
+int flashReadBytes(uint32_t address, uint8_t *buffer, int length)
+{
+    return flashDevice.vTable->readBytes(&flashDevice, address, buffer, length);
+}
+
+void flashFlush(void)
+{
+    flashDevice.vTable->flush(&flashDevice);
+}
+
+static const flashGeometry_t noFlashGeometry = {
+    .totalSize = 0,
+};
+
+const flashGeometry_t *flashGetGeometry(void)
+{
+    if (flashDevice.vTable && flashDevice.vTable->getGeometry) {
+        return flashDevice.vTable->getGeometry(&flashDevice);
+    }
+
+    return &noFlashGeometry;
+}
+#endif // USE_FLASH