diff options
Diffstat (limited to 'rv64cpu/rtl/core/mmu/tlb.sv')
| -rw-r--r-- | rv64cpu/rtl/core/mmu/tlb.sv | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/rv64cpu/rtl/core/mmu/tlb.sv b/rv64cpu/rtl/core/mmu/tlb.sv index e4696fd..06eb947 100644 --- a/rv64cpu/rtl/core/mmu/tlb.sv +++ b/rv64cpu/rtl/core/mmu/tlb.sv @@ -15,7 +15,7 @@ // along with this program. If not, see <https://www.gnu.org/licenses/>. // File path: rtl/core/mmu/tlb.sv -// Description: Parameterized L1 TLB (Sv32/Sv48/Sv57) +// Description: Parameterized L1 TLB (Bare + Sv39, higher modes stubbed) module tlb import rv64_pkg::*; @@ -69,9 +69,10 @@ module tlb ); localparam logic [3:0] SATP_MODE_BARE = 4'd0; - localparam logic [3:0] SATP_MODE_SV32 = 4'd1; + localparam logic [3:0] SATP_MODE_SV39 = 4'd8; localparam logic [3:0] SATP_MODE_SV48 = 4'd9; localparam logic [3:0] SATP_MODE_SV57 = 4'd10; + localparam logic [3:0] SATP_MODE_SV64 = 4'd11; // Reserved/future stub. typedef struct packed { logic valid; @@ -105,24 +106,19 @@ module tlb int unsigned shift_index; function automatic logic is_supported_mode(input logic [3:0] mode); - return (mode == SATP_MODE_BARE) || (mode == SATP_MODE_SV32) || - (mode == SATP_MODE_SV48) || (mode == SATP_MODE_SV57); + return (mode == SATP_MODE_BARE) || (mode == SATP_MODE_SV39); endfunction function automatic int vpn_width(input logic [3:0] mode); case (mode) - SATP_MODE_SV32: vpn_width = 20; - SATP_MODE_SV48: vpn_width = 36; - SATP_MODE_SV57: vpn_width = 45; + SATP_MODE_SV39: vpn_width = 27; default: vpn_width = 0; endcase endfunction function automatic int vpn_stride(input logic [3:0] mode); case (mode) - SATP_MODE_SV32: vpn_stride = 10; - SATP_MODE_SV48, - SATP_MODE_SV57: vpn_stride = 9; + SATP_MODE_SV39: vpn_stride = 9; default: vpn_stride = 0; endcase endfunction @@ -160,15 +156,23 @@ module tlb begin vpn = '0; case (mode) - SATP_MODE_SV32: vpn[19:0] = vaddr[31:12]; - SATP_MODE_SV48: vpn[35:0] = vaddr[47:12]; - SATP_MODE_SV57: vpn[44:0] = vaddr[56:12]; + SATP_MODE_SV39: vpn[26:0] = vaddr[38:12]; default: vpn = '0; endcase vaddr_to_vpn = vpn; end endfunction + function automatic logic vaddr_is_canonical( + input logic [XLEN-1:0] vaddr, + input logic [3:0] mode + ); + case (mode) + SATP_MODE_SV39: vaddr_is_canonical = (vaddr[63:39] == {25{vaddr[38]}}); + default: vaddr_is_canonical = 1'b1; + endcase + endfunction + function automatic logic [5:0] page_shift( input logic [3:0] mode, input logic [2:0] level @@ -262,7 +266,7 @@ module tlb hit_d = 1'b0; if (req_valid) begin - if (!is_supported_mode(req_mode)) begin + if (!is_supported_mode(req_mode) || !vaddr_is_canonical(req_vaddr, req_mode)) begin resp_page_fault = 1'b1; end else if (req_mode == SATP_MODE_BARE || req_priv == 2'b11) begin // Bare mode or M-mode bypasses translation. |