add XTAL freq getter and add cpu freq validation

Author: me-no-dev

Diff for: cores/esp32/esp32-hal-cpu.c

@@ -126,9 +126,32 @@ static uint32_t calculateApb(rtc_cpu_freq_config_t * conf){
 
 void esp_timer_impl_update_apb_freq(uint32_t apb_ticks_per_us); //private in IDF
 
-bool setCpuFrequency(uint32_t cpu_freq_mhz){
+bool setCpuFrequencyMhz(uint32_t cpu_freq_mhz){
     rtc_cpu_freq_config_t conf, cconf;
     uint32_t capb, apb;
+    //Get XTAL Frequency and calculate min CPU MHz
+    rtc_xtal_freq_t xtal = rtc_clk_xtal_freq_get();
+    uint32_t min_cpu_mhz = 10;
+    if(xtal > RTC_XTAL_FREQ_AUTO){
+        if(xtal < RTC_XTAL_FREQ_40M) {
+            min_cpu_mhz = xtal / 2; //13Mhz for 26Mhz XTAL
+            if(cpu_freq_mhz <= xtal && cpu_freq_mhz != xtal && cpu_freq_mhz != (xtal/2)){
+                log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2);
+                return false;
+            }
+        } else if(cpu_freq_mhz <= xtal && cpu_freq_mhz != xtal && cpu_freq_mhz != (xtal/2) && cpu_freq_mhz != (xtal/4)){
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2, xtal/4);
+            return false;
+        }
+    }
+    if(cpu_freq_mhz > xtal && cpu_freq_mhz != 240 && cpu_freq_mhz != 160 && cpu_freq_mhz != 80){
+        if(xtal >= RTC_XTAL_FREQ_40M){
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2, xtal/4);
+        } else {
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2);
+        }
+        return false;
+    }
     //Get current CPU clock configuration
     rtc_clk_cpu_freq_get_config(&cconf);
     //return if frequency has not changed
@@ -144,7 +167,7 @@ bool setCpuFrequency(uint32_t cpu_freq_mhz){
     capb = calculateApb(&cconf);
     //New APB
     apb = calculateApb(&conf);
-    log_i("%s: %u / %u = %u Mhz, APB: %u Hz", (conf.source == RTC_CPU_FREQ_SRC_PLL)?"PLL":((conf.source == RTC_CPU_FREQ_SRC_APLL)?"APLL":((conf.source == RTC_CPU_FREQ_SRC_XTAL)?"XTAL":"8M")), conf.source_freq_mhz, conf.div, conf.freq_mhz, apb);
+    log_d("%s: %u / %u = %u Mhz, APB: %u Hz", (conf.source == RTC_CPU_FREQ_SRC_PLL)?"PLL":((conf.source == RTC_CPU_FREQ_SRC_APLL)?"APLL":((conf.source == RTC_CPU_FREQ_SRC_XTAL)?"XTAL":"8M")), conf.source_freq_mhz, conf.div, conf.freq_mhz, apb);
     //Call peripheral functions before the APB change
     if(apb_change_callbacks){
         triggerApbChangeCallback(APB_BEFORE_CHANGE, capb, apb);
@@ -171,12 +194,16 @@ bool setCpuFrequency(uint32_t cpu_freq_mhz){
     return true;
 }
 
-uint32_t getCpuFrequency(){
+uint32_t getCpuFrequencyMhz(){
     rtc_cpu_freq_config_t conf;
     rtc_clk_cpu_freq_get_config(&conf);
     return conf.freq_mhz;
 }
 
+uint32_t getXtalFrequencyMhz(){
+    return rtc_clk_xtal_freq_get();
+}
+
 uint32_t getApbFrequency(){
     rtc_cpu_freq_config_t conf;
     rtc_clk_cpu_freq_get_config(&conf);

Diff for: cores/esp32/esp32-hal-cpu.h

@@ -31,14 +31,15 @@ bool addApbChangeCallback(void * arg, apb_change_cb_t cb);
 bool removeApbChangeCallback(void * arg, apb_change_cb_t cb);
 
 //function takes the following frequencies as valid values:
-//  240, 160, 80                     <<< For all XTAL types
-//  40, 20, 13, 10, 8, 5, 4, 3, 2, 1 <<< For 40MHz XTAL
-//  26, 13, 5, 4, 3, 2, 1            <<< For 26MHz XTAL
-//  24, 12, 8, 6, 4, 3, 2, 1         <<< For 24MHz XTAL
-bool setCpuFrequency(uint32_t cpu_freq_mhz);
-
-uint32_t getCpuFrequency(); // In MHz
-uint32_t getApbFrequency(); // In Hz
+//  240, 160, 80    <<< For all XTAL types
+//  40, 20, 10      <<< For 40MHz XTAL
+//  26, 13          <<< For 26MHz XTAL
+//  24, 12          <<< For 24MHz XTAL
+bool setCpuFrequencyMhz(uint32_t cpu_freq_mhz);
+
+uint32_t getCpuFrequencyMhz();  // In MHz
+uint32_t getXtalFrequencyMhz(); // In MHz
+uint32_t getApbFrequency();     // In Hz
 
 #ifdef __cplusplus
 }

Diff for: cores/esp32/esp32-hal-misc.c

@@ -149,7 +149,7 @@ void initArduino()
     //init proper ref tick value for PLL (uncomment if REF_TICK is different than 1MHz)
     //ESP_REG(APB_CTRL_PLL_TICK_CONF_REG) = APB_CLK_FREQ / REF_CLK_FREQ - 1;
 #ifdef F_CPU
-    setCpuFrequency(F_CPU/1000000);
+    setCpuFrequencyMhz(F_CPU/1000000);
 #endif
 #if CONFIG_SPIRAM_SUPPORT
     psramInit();