Scalable Clocks (AMD Alveo™ Platforms only)
An AMD
Alveo platform provides a frequency scalable kernel clock
with ID (or Index) 0 that drives all XRT managed kernels. XRT can set the clock frequency of
this clock according to the metadata contained in the xclbin file, when loading the file. An Alveo platform also provides a second scalable clock with ID 1 that is also
controllable based on xclbin metadata. You do not
need to provide an option to connect to scalable clocks, but you can specify the clock
frequency during v++ linking using the --freqhz option or --kernel_frequency, as described in
v++ General
Options in the Vitis
Reference Guide (UG1702). The v++ linker automatically connects PL kernel clocks ap_clk to clock ID 0, and ap_clk2 to clock ID
1.
ap_clk2 is primarily found on RTL kernels, because the HLS
compiler does not generate kernels with multiple clocks.You can determine the clocks available in the target platform by using
the platforminfo command.
=================
Clock Information
=================
Default Clock Index: 2
Default Clock Frequency: 312.499712
Default Clock Pretty Name: PL 2
Clock Index: 0
Frequency: 156.249856
Status: fixed
Name: clk_wizard_0_clk_out2
Pretty Name: PL 0
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 6.400006
Normalized Period: .006400
Clock Index: 1
Frequency: 104.166570
Status: fixed
Name: clk_wizard_0_clk_out1
Pretty Name: PL 1
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 9.600009
Normalized Period: .009600
Clock Index: 2
Frequency: 312.499712
Status: fixed
Name: clk_wizard_0_clk_out3
Pretty Name: PL 2
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 3.200003
Normalized Period: .003200
Clock Index: 3
Frequency: 78.124928
Status: fixed
Name: clk_wizard_0_clk_out4
Pretty Name: PL 3
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 12.800012
Normalized Period: .012800
Clock Index: 4
Frequency: 208.333141
Status: fixed
Name: clk_wizard_0_clk_out5
Pretty Name: PL 4
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 4.800004
Normalized Period: .004800
Clock Index: 5
Frequency: 416.666283
Status: fixed
Name: clk_wizard_0_clk_out6
Pretty Name: PL 5
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 2.400002
Normalized Period: .002400
Clock Index: 6
Frequency: 624.999425
Status: fixed
Name: clk_wizard_0_clk_out7
Pretty Name: PL 6
Inst Ref: clk_wizard_0
Comp Ref: clk_wizard
Period: 1.600001
Normalized Period: .001600