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Altera_Forum
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8 years ago

Arria 10 PCIe Gen 3 timing violations in Quartus 17.0.2

I got timing violations in Arria 10 PCIe Gen 3 design after upgrading to Quartus 17.0.2. The same design compiles without timing violations in Quartus 16.

Path# 1: Setup slack is -4.551 (VIOLATED)
; From Node          ; top:top|top_altera_pcie_a10_hip_170_ueiagsq:pcie_a10_hip_0|altpcie_a10_hip_pipen1b:altpcie_a10_hip_pipen1b|wys~ch3_pcs_chnl_hip_clk_out.reg
; To Node            ; top:top|top_altera_pcie_a10_hip_170_ueiagsq:pcie_a10_hip_0|altpcie_a10_hip_pipen1b:altpcie_a10_hip_pipen1b|altpcie_a10_hip_pllnphy:g_xcvr.altpcie_a10_hip_pllnphy|phy_g3x8:g_xcvr.g_phy_g3x8.phy_g3
x8|top_altera_xcvr_native_a10_170_ylcxrpq:phy_g3x8|twentynm_xcvr_native:g_xcvr_native_insts.twentynm_xcvr_native_inst|twentynm_xcvr_native_rev_20nm2:twentynm_xcvr_native_inst|twentynm_pcs_rev_20nm2:inst_twentynm_pcs
|gen_twentynm_hssi_common_pld_pcs_interface.inst_twentynm_hssi_common_pld_pcs_interface~pld_rate_reg.reg ;
; Launch Clock       ; top|pcie_a10_hip_0|tx_serial_clk
; Latch Clock        ; top|pcie_a10_hip_0|pll_serial_clk_8g
; Data Arrival Time  ; 7.020
; Data Required Time ; 2.469
; Slack              ; -4.551 (VIOLATED)
+---------------------------------------------------------------------------------------+
; Statistics                                                                            ;
+---------------------------+--------+-------+-------------+------------+-------+-------+
; Property                  ; Value  ; Count ; Total Delay ; % of Total ; Min   ; Max   ;
+---------------------------+--------+-------+-------------+------------+-------+-------+
; Setup Relationship        ; 0.050  ;       ;             ;            ;       ;       ;
; Clock Skew                ; -1.856 ;       ;             ;            ;       ;       ;
; Data Delay                ; 2.221  ;       ;             ;            ;       ;       ;
; Number of Logic Levels    ;        ; 0     ;             ;            ;       ;       ;
; Physical Delays           ;        ;       ;             ;            ;       ;       ;
;  Arrival Path             ;        ;       ;             ;            ;       ;       ;
;   Clock                   ;        ;       ;             ;            ;       ;       ;
;    Clock Network (Lumped) ;        ; 1     ; 3.599       ; 100        ; 3.599 ; 3.599 ;
;   Data                    ;        ;       ;             ;            ;       ;       ;
;    IC                     ;        ; 1     ; 0.001       ; 0          ; 0.001 ; 0.001 ;
;    Cell                   ;        ; 1     ; 0.000       ; 0          ; 0.000 ; 0.000 ;
;    uTco                   ;        ; 1     ; 2.220       ; 100        ; 2.220 ; 2.220 ;
;  Required Path            ;        ;       ;             ;            ;       ;       ;
;   Clock                   ;        ;       ;             ;            ;       ;       ;
;    Clock Network (Lumped) ;        ; 1     ; 1.743       ; 100        ; 1.743 ; 1.743 ;
+---------------------------+--------+-------+-------------+------------+-------+-------+

The problem is that this path is completely inside encrypted part of PCIe IP.

Is there a workaround? Quartus bug fix?

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Hi sols,

    Upgrade to Quartus 17.1 version. The timing of PCIe have been changed a lot and most of violations are removed.

    If you are using 128 bit 250 MHz clock(Gen 3 configuration of PCIe) and not seeing timing violation in PCIe, let me know as I am facing setup violations -0.5 to -0.6 in core clkout.