From e7a6bde56dab910b4a600d0d8301fbe74a69273a Mon Sep 17 00:00:00 2001
From: Oleksandr Grytsov <al1img@gmail.com>
Date: Mon, 21 Jan 2019 23:15:12 +0200
Subject: [PATCH] [samr21] Implement otPlatLog for SAMR21 XPLAINED PRO board
 (#3491)

Use EDBG DGI SPI interface to put log.

Signed-off-by: Oleksandr Grytsov <al1img@gmail.com>
---
 examples/platforms/samr21/logging.c         | 85 +++++++++++++++++++++
 examples/platforms/samr21/platform-samr21.h |  8 +-
 examples/platforms/samr21/system.c          |  5 ++
 3 files changed, 97 insertions(+), 1 deletion(-)

diff --git a/examples/platforms/samr21/logging.c b/examples/platforms/samr21/logging.c
index 4d3023e46..a8f938aa9 100644
--- a/examples/platforms/samr21/logging.c
+++ b/examples/platforms/samr21/logging.c
@@ -33,16 +33,101 @@
  */
 
 #include <openthread-core-config.h>
+#include <utils/code_utils.h>
 #include <openthread/config.h>
 #include <openthread/platform/logging.h>
 #include <openthread/platform/toolchain.h>
 
 #if (OPENTHREAD_CONFIG_LOG_OUTPUT == OPENTHREAD_CONFIG_LOG_OUTPUT_PLATFORM_DEFINED) || \
     (OPENTHREAD_CONFIG_LOG_OUTPUT == OPENTHREAD_CONFIG_LOG_OUTPUT_NCP_SPINEL)
+
+#if BOARD == SAMR21_XPLAINED_PRO
+
+#include "board.h"
+#include "spi.h"
+
+#define LOG_PARSE_BUFFER_SIZE 128
+#define LOG_TIMESTAMP_ENABLE 1
+
+struct spi_module     sMaster;
+struct spi_slave_inst sSlave;
+
+char sLogString[LOG_PARSE_BUFFER_SIZE + 1];
+
+static void logOutput(otLogLevel aLogLevel, otLogRegion aLogRegion, const char *aFormat, va_list ap)
+{
+    int len = 0;
+
+    len = vsnprintf(sLogString, LOG_PARSE_BUFFER_SIZE, aFormat, ap);
+
+    otEXPECT(len >= 0);
+
+exit:
+
+    if (len >= LOG_PARSE_BUFFER_SIZE)
+    {
+        len = LOG_PARSE_BUFFER_SIZE - 1;
+    }
+
+    sLogString[len++] = '\n';
+
+    spi_select_slave(&sMaster, &sSlave, true);
+
+    spi_write_buffer_wait(&sMaster, (uint8_t *)sLogString, len);
+
+    spi_select_slave(&sMaster, &sSlave, false);
+
+    return;
+}
+
+#endif
+
+void samr21LogInit(void)
+{
+#if BOARD == SAMR21_XPLAINED_PRO
+
+    struct spi_slave_inst_config slaveConfig;
+    struct spi_config            config;
+
+    spi_slave_inst_get_config_defaults(&slaveConfig);
+
+    slaveConfig.ss_pin = EDBG_SPI_SLAVE_SELECT_PIN;
+
+    spi_attach_slave(&sSlave, &slaveConfig);
+
+    spi_get_config_defaults(&config);
+
+    config.mux_setting                   = EDBG_SPI_SERCOM_MUX_SETTING;
+    config.mode_specific.master.baudrate = 8000000UL;
+    config.pinmux_pad0                   = EDBG_SPI_SERCOM_PINMUX_PAD0;
+    config.pinmux_pad1                   = EDBG_SPI_SERCOM_PINMUX_PAD1;
+    config.pinmux_pad2                   = EDBG_SPI_SERCOM_PINMUX_PAD2;
+    config.pinmux_pad3                   = EDBG_SPI_SERCOM_PINMUX_PAD3;
+
+    spi_init(&sMaster, EDBG_SPI_MODULE, &config);
+    spi_enable(&sMaster);
+
+#endif
+}
+
 OT_TOOL_WEAK void otPlatLog(otLogLevel aLogLevel, otLogRegion aLogRegion, const char *aFormat, ...)
 {
+#if BOARD == SAMR21_XPLAINED_PRO
+    va_list ap;
+
+    va_start(ap, aFormat);
+
+    logOutput(aLogLevel, aLogRegion, aFormat, ap);
+
+    va_end(ap);
+
+#else
+
     OT_UNUSED_VARIABLE(aLogLevel);
     OT_UNUSED_VARIABLE(aLogRegion);
     OT_UNUSED_VARIABLE(aFormat);
+
+#endif
 }
+
 #endif
diff --git a/examples/platforms/samr21/platform-samr21.h b/examples/platforms/samr21/platform-samr21.h
index 237087052..5c30979b5 100644
--- a/examples/platforms/samr21/platform-samr21.h
+++ b/examples/platforms/samr21/platform-samr21.h
@@ -100,4 +100,10 @@ void samr21UartProcess(void);
  */
 void samr21GetIeeeEui64(otInstance *aInstance, uint8_t *aIeeeEui64);
 
-#endif  // PLATFORM_SAMR21_H_
+/**
+ * Initialization of Logger driver.
+ *
+ */
+void samr21LogInit(void);
+
+#endif // PLATFORM_SAMR21_H_
diff --git a/examples/platforms/samr21/system.c b/examples/platforms/samr21/system.c
index 0c237272c..804f1c66d 100644
--- a/examples/platforms/samr21/system.c
+++ b/examples/platforms/samr21/system.c
@@ -34,6 +34,7 @@
 
 #include "asf.h"
 
+#include <openthread-core-config.h>
 #include <openthread/platform/radio.h>
 
 #include "openthread-system.h"
@@ -173,6 +174,10 @@ void otSysInit(int argc, char *argv[])
     getKitData();
 #endif
 
+#if (OPENTHREAD_CONFIG_LOG_OUTPUT == OPENTHREAD_CONFIG_LOG_OUTPUT_PLATFORM_DEFINED) || \
+    (OPENTHREAD_CONFIG_LOG_OUTPUT == OPENTHREAD_CONFIG_LOG_OUTPUT_NCP_SPINEL)
+    samr21LogInit();
+#endif
     samr21AlarmInit();
     samr21RadioInit();
 }