Enable external clock selection on MAX32657

Now that external clock selection bits are defined, uncomment code to allow external clock to be used. Signed-off-by: Tahsin Mutlugun <[email protected]>
analogdevicesinc · Dec 13, 2024 · b5a4bd7 · b5a4bd7
1 parent eeb59b5
commit b5a4bd7
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Showing 5 changed files with 37 additions and 37 deletions.
diff --git a/Libraries/CMSIS/Device/Maxim/MAX32657/Source/system_max32657.c b/Libraries/CMSIS/Device/Maxim/MAX32657/Source/system_max32657.c
@@ -80,10 +80,9 @@ __weak void SystemCoreClockUpdate(void)
     case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_ERTCO:
         base_freq = ERTCO_FREQ;
         break;
-    // case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK:
-    //     base_freq = EXTCLK_FREQ;
-    //     break;
-    // TODO(JC): ^^^ Uncomment when EXTCLK register definition is added
+    case MXC_S_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK:
+        base_freq = EXTCLK_FREQ;
+        break;
     default:
         // Codes 001 and 111 are reserved.
         // This code should never execute, however, initialize to safe value.

diff --git a/Libraries/PeriphDrivers/Include/MAX32657/mxc_pins.h b/Libraries/PeriphDrivers/Include/MAX32657/mxc_pins.h
@@ -28,6 +28,7 @@
 
 /***** Global Variables *****/
 // Predefined GPIO Configurations
+extern const mxc_gpio_cfg_t gpio_cfg_extclk;
 extern const mxc_gpio_cfg_t gpio_cfg_i3c;
 
 extern const mxc_gpio_cfg_t gpio_cfg_uart;

diff --git a/Libraries/PeriphDrivers/Include/MAX32657/mxc_sys.h b/Libraries/PeriphDrivers/Include/MAX32657/mxc_sys.h
@@ -99,9 +99,8 @@ typedef enum {
         MXC_V_GCR_CLKCTRL_SYSCLK_SEL_INRO, /**< Select the Internal Nanoring Oscillator (INRO) */
     MXC_SYS_CLOCK_ERTCO =
         MXC_V_GCR_CLKCTRL_SYSCLK_SEL_ERTCO, /**< Select the External RTC Crystal Oscillator */
-    // MXC_SYS_CLOCK_EXTCLK =
-    //     MXC_V_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK /**< Use the external system clock input */
-    // TODO(JC): ^^^ EXTCLK select is missing from gcr_regs.h (should be 0x7)
+    MXC_SYS_CLOCK_EXTCLK =
+        MXC_V_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK /**< Use the external system clock input */
 } mxc_sys_system_clock_t;
 
 /** @brief Enumeration to set the System Clock divider */

diff --git a/Libraries/PeriphDrivers/Source/SYS/pins_me30.c b/Libraries/PeriphDrivers/Source/SYS/pins_me30.c
@@ -24,6 +24,9 @@
 /***** Global Variables *****/
 
 // clang-format off
+const mxc_gpio_cfg_t gpio_cfg_extclk = { MXC_GPIO0, (MXC_GPIO_PIN_7), MXC_GPIO_FUNC_IN,
+                                         MXC_GPIO_PAD_NONE, MXC_GPIO_VSSEL_VDDIO, MXC_GPIO_DRVSTR_0 };
+
 // P0.0 - I3C SCL
 // P0.1 - I3C SDA
 const mxc_gpio_cfg_t gpio_cfg_i3c = { MXC_GPIO0, (MXC_GPIO_PIN_0 | MXC_GPIO_PIN_1), MXC_GPIO_FUNC_ALT1,

diff --git a/Libraries/PeriphDrivers/Source/SYS/sys_me30.c b/Libraries/PeriphDrivers/Source/SYS/sys_me30.c
@@ -226,11 +226,10 @@ int MXC_SYS_ClockSourceEnable(mxc_sys_system_clock_t clock)
         return MXC_SYS_Clock_Timeout(MXC_F_GCR_CLKCTRL_IBRO_RDY);
         break;
 
-        // TODO(ME30): EXTCLK is missing from register definitions
-        // case MXC_SYS_CLOCK_EXTCLK:
-        //     // No "RDY" bit to monitor, so just configure the GPIO
-        //     return MXC_GPIO_Config(&gpio_cfg_extclk);
-        //     break;
+    case MXC_SYS_CLOCK_EXTCLK:
+        // No "RDY" bit to monitor, so just configure the GPIO
+        return MXC_GPIO_Config(&gpio_cfg_extclk);
+        break;
 
     case MXC_SYS_CLOCK_INRO:
         // The 80k clock is always enabled
@@ -291,16 +290,15 @@ int MXC_SYS_ClockSourceDisable(mxc_sys_system_clock_t clock)
         MXC_GCR->clkctrl &= ~MXC_F_GCR_CLKCTRL_IBRO_EN;
         break;
 
-        // TODO(ME30): Missing EXTCLK register definition
-        // case MXC_SYS_CLOCK_EXTCLK:
-        //     /*
-        //     There's not a great way to disable the external clock.
-        //     Deinitializing the GPIO here may have unintended consequences
-        //     for application code.
-        //     Selecting a different system clock source is sufficient
-        //     to "disable" the EXT_CLK source.
-        //     */
-        //     break;
+    case MXC_SYS_CLOCK_EXTCLK:
+        /*
+        There's not a great way to disable the external clock.
+        Deinitializing the GPIO here may have unintended consequences
+        for application code.
+        Selecting a different system clock source is sufficient
+        to "disable" the EXT_CLK source.
+        */
+        break;
 
     case MXC_SYS_CLOCK_INRO:
         // The 80k clock is always enabled
@@ -353,6 +351,7 @@ int MXC_SYS_Clock_Timeout(uint32_t ready)
 int MXC_SYS_Clock_Select(mxc_sys_system_clock_t clock)
 {
     uint32_t current_clock;
+    int err = E_NO_ERROR;
 
     // Save the current system clock
     current_clock = MXC_GCR->clkctrl & MXC_F_GCR_CLKCTRL_SYSCLK_SEL;
@@ -394,21 +393,20 @@ int MXC_SYS_Clock_Select(mxc_sys_system_clock_t clock)
 
         break;
 
-        // TODO(ME30): Missing EXTCLK register definition
-        // case MXC_SYS_CLOCK_EXTCLK:
-        //     /*
-        //     There's not "EXT_CLK RDY" bit for the ME17, so we'll
-        //     blindly enable (configure GPIO) the external clock every time.
-        //     */
-        //     err = MXC_SYS_ClockSourceEnable(MXC_SYS_CLOCK_EXTCLK);
-        //     if (err)
-        //         return err;
-
-        //     // Set EXT clock as System Clock
-        //     MXC_SETFIELD(MXC_GCR->clkctrl, MXC_F_GCR_CLKCTRL_SYSCLK_SEL,
-        //                  MXC_S_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK);
-
-        //     break;
+    case MXC_SYS_CLOCK_EXTCLK:
+        /*
+        There's not "EXT_CLK RDY" bit for the ME17, so we'll
+        blindly enable (configure GPIO) the external clock every time.
+        */
+        err = MXC_SYS_ClockSourceEnable(MXC_SYS_CLOCK_EXTCLK);
+        if (err)
+            return err;
+
+        // Set EXT clock as System Clock
+        MXC_SETFIELD(MXC_GCR->clkctrl, MXC_F_GCR_CLKCTRL_SYSCLK_SEL,
+                        MXC_S_GCR_CLKCTRL_SYSCLK_SEL_EXTCLK);
+
+        break;
 
     case MXC_SYS_CLOCK_ERFO: