Hi nordic team
I am working with the Nordic nRF5340 SoC using Zephyr RTOS.
Hardware
External QSPI flash:
-
MX25R6435F
QSPI configuration (DeviceTree):
&qspi {
status = "okay";
pinctrl-0 = <&qspi_default>;
pinctrl-1 = <&qspi_sleep>;
pinctrl-names = "default", "sleep";
mx25r64: mx25r6435f@0 {
compatible = "nordic,qspi-nor";
reg = <0>;
sck-frequency = <32000000>;
readoc = "read4io";
jedec-id = [ c2 20 1a ];
/delete-property/ sfdp-bfp;
size = <536870912>;
address-size-32;
enter-4byte-addr = <0x01>;
has-dpd;
t-enter-dpd = <10000>;
t-exit-dpd = <35000>;
status = "okay";
partitions {
compatible = "fixed-partitions";
#address-cells = <1>;
#size-cells = <1>;
/* 0x00000000 - 0x007FFFFF : 8MB raw I2S / reserved */
raw_rec_part: partition@0 {
label = "raw_rec";
reg = <0x00000000 0x00800000>;
};
/* 0x00800000 - 0x03FFFFFF: 56MB FATFS */
fatfs_part: partition@800000 {
label = "fatfs";
reg = <0x00800000 0x03800000>;
};
};
};
};
the QSPI SCK clock = 32 MHz.
The application core CPU frequency = 128 MHz.
I am configuring the CPU to run at 128 MHz uisng the below api
void set_cpu_128mhz(void)
{
// Direct register access to set the clock divider to 1 (128MHz)
// 0 = 128MHz, 1 = 64MHz
NRF_CLOCK_S->HFCLKCTRL = 0;
// Update the system variable so timing functions (like your us conversion) are accurate
SystemCoreClockUpdate();
printf("SystemCoreClock: %u MHz\n", (unsigned int)(SystemCoreClock / 1000000));
}
Issue observed :
When the CPU runs at 128 MHz:
-
Flash read operations fail
-
Flash write operations fail
why QSPI flash read/write fails when the CPU runs at 128 MHz while the QSPI SCK is configured at 32 MHz?
Any insights on this issue would be helpful.
