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authorSteffen Görtz <contrib@steffen-goertz.de>2019-01-29 11:46:03 +0000
committerPeter Maydell <peter.maydell@linaro.org>2019-01-29 11:46:03 +0000
commit9d68bf564ecd038c8939b9779f4b6d62a01ce6f3 (patch)
tree0609383cbf6e3b8a635fcff272ecfd4d4cb27d6d /include/hw/i2c
parentab65eed3f82b57459ef8c45f75a89241f16cbad8 (diff)
arm: Stub out NRF51 TWI magnetometer/accelerometer detection
Recent microbit firmwares panic if the TWI magnetometer/accelerometer devices are not detected during startup. We don't implement TWI (I2C) so let's stub out these devices just to let the firmware boot. Signed-off by: Steffen Görtz <contrib@steffen-goertz.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20190110094020.18354-2-stefanha@redhat.com Reviewed-by: Peter Maydell <peter.maydell@linaro.org> [PMM: fixed comment style] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'include/hw/i2c')
-rw-r--r--include/hw/i2c/microbit_i2c.h42
1 files changed, 42 insertions, 0 deletions
diff --git a/include/hw/i2c/microbit_i2c.h b/include/hw/i2c/microbit_i2c.h
new file mode 100644
index 0000000000..aad636127e
--- /dev/null
+++ b/include/hw/i2c/microbit_i2c.h
@@ -0,0 +1,42 @@
+/*
+ * Microbit stub for Nordic Semiconductor nRF51 SoC Two-Wire Interface
+ * http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.1.pdf
+ *
+ * Copyright 2019 Red Hat, Inc.
+ *
+ * This code is licensed under the GPL version 2 or later. See
+ * the COPYING file in the top-level directory.
+ */
+
+#ifndef MICROBIT_I2C_H
+#define MICROBIT_I2C_H
+
+#include "hw/sysbus.h"
+#include "hw/arm/nrf51.h"
+
+#define NRF51_TWI_TASK_STARTRX 0x000
+#define NRF51_TWI_TASK_STARTTX 0x008
+#define NRF51_TWI_TASK_STOP 0x014
+#define NRF51_TWI_EVENT_STOPPED 0x104
+#define NRF51_TWI_EVENT_RXDREADY 0x108
+#define NRF51_TWI_EVENT_TXDSENT 0x11c
+#define NRF51_TWI_REG_ENABLE 0x500
+#define NRF51_TWI_REG_RXD 0x518
+#define NRF51_TWI_REG_TXD 0x51c
+#define NRF51_TWI_REG_ADDRESS 0x588
+
+#define TYPE_MICROBIT_I2C "microbit.i2c"
+#define MICROBIT_I2C(obj) \
+ OBJECT_CHECK(MicrobitI2CState, (obj), TYPE_MICROBIT_I2C)
+
+#define MICROBIT_I2C_NREGS (NRF51_TWI_SIZE / sizeof(uint32_t))
+
+typedef struct {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+ uint32_t regs[MICROBIT_I2C_NREGS];
+ uint32_t read_idx;
+} MicrobitI2CState;
+
+#endif /* MICROBIT_I2C_H */