Adding RP2350 SDK and target framework (#13988)

* Adding RP2350 SDK and target framework

* Spacing

* Removing board definitions

lib/main/pico-sdk/rp2_common/pico_stdio_semihosting/include/pico/stdio_semihosting.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef _PICO_STDIO_SEMIHOSTING_H
+#define _PICO_STDIO_SEMIHOSTING_H
+
+#include "pico/stdio.h"
+
+/** \brief Experimental support for stdout using RAM semihosting
+ *  \defgroup pico_stdio_semihosting pico_stdio_semihosting
+ *  \ingroup pico_stdio
+ *
+ *  Linking this library or calling `pico_enable_stdio_semihosting(TARGET ENABLED)` in the CMake (which
+ *  achieves the same thing) will add semihosting to the drivers used for standard output
+ */
+
+// PICO_CONFIG: PICO_STDIO_SEMIHOSTING_DEFAULT_CRLF, Default state of CR/LF translation for semihosting output, type=bool, default=PICO_STDIO_DEFAULT_CRLF, group=pico_stdio_semihosting
+#ifndef PICO_STDIO_SEMIHOSTING_DEFAULT_CRLF
+#define PICO_STDIO_SEMIHOSTING_DEFAULT_CRLF PICO_STDIO_DEFAULT_CRLF
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern stdio_driver_t stdio_semihosting;
+
+/*! \brief Explicitly initialize stdout over semihosting and add it to the current set of stdout targets
+ *  \ingroup pico_stdio_semihosting
+ *
+ * \note this method is automatically called by \ref stdio_init_all() if `pico_stdio_semihosting` is included in the build
+ */
+void stdio_semihosting_init(void);
+
+/*! \brief Explicitly deinitialize stdout over semihosting and add it to the current set of stdout targets
+ *  \ingroup pico_stdio_semihosting
+ *
+ * \note this method is automatically called by \ref stdio_deinit_all() if `pico_stdio_semihosting` is included in the build
+ */
+void stdio_semihosting_deinit(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

lib/main/pico-sdk/rp2_common/pico_stdio_semihosting/stdio_semihosting.c

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+/*
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "pico/stdio/driver.h"
+#include "pico/stdio_semihosting.h"
+#include "pico/binary_info.h"
+
+static void stdio_semihosting_out_chars(const char *buf, int length) {
+    // must be volatile or the buffer gets put in registers & optimized away
+    volatile struct {
+        // https://developer.arm.com/documentation/dui0375/g/What-is-Semihosting-/SYS-WRITE--0x05-
+        // arguments, in order:
+        // word 0 = file handle (1 = stdout)
+        // word 1 = pointer to buffer
+        // word 2 = length of buffer
+        size_t fd;
+        const char *buf;
+        size_t len;
+    } args;
+
+    args.fd = 1;  // 1 = stdout
+    args.buf = buf;
+    args.len = length;
+
+    pico_default_asm (
+#ifdef __riscv
+        // a0 encodes the semihosting call number, 0x05 = SYS_WRITE
+        "li a0, 0x05\n"
+        // a1 points to the arguments
+        "mv a1, %[args]\n"
+        // Magic three-instruction sequence, containing a breakpoint. Note the
+        // RISC-V unpriv spec implies the final instruction might encode the
+        // call number (passed in a1) but openocd source shows this is just a
+        // constant value of 0x07. These instructions must be uncompressed:
+        ".option push\n"
+        ".option norvc\n"
+        "slli x0, x0, 0x1f\n"
+        "ebreak\n"
+        "srai x0, x0, 0x07\n"
+        ".option pop\n"
+        :
+        : [args] "r" (&args)
+        : "a0", "a1"
+#else
+        // r1 must contain a pointer to the arguments
+        "movs r1, %[args]\n"
+        // semihosting call number 0x05 = SYS_WRITE
+        "movs r0, #5\n"
+        // make the semihosting call: https://developer.arm.com/documentation/dui0375/g/What-is-Semihosting-/The-semihosting-interface
+        "bkpt 0xab\n"
+        :
+        : [args] "r" (&args)
+        : "r0", "r1", "cc", "memory"
+#endif
+    );
+}
+
+stdio_driver_t stdio_semihosting = {
+        .out_chars = stdio_semihosting_out_chars,
+#if PICO_STDIO_ENABLE_CRLF_SUPPORT
+        .crlf_enabled = PICO_STDIO_SEMIHOSTING_DEFAULT_CRLF
+#endif
+};
+
+void stdio_semihosting_init(void) {
+#if !PICO_NO_BI_STDIO_SEMIHOSTING
+    bi_decl_if_func_used(bi_program_feature("semihosting stdout"));
+#endif
+    stdio_set_driver_enabled(&stdio_semihosting, true);
+}
+
+void stdio_semihosting_deinit(void) {
+    stdio_set_driver_enabled(&stdio_semihosting, false);
+}