From b0e15f2fb510427f4a3b652453ea2e82ae8aac02 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 5 Jun 2020 11:45:00 +1000 Subject: [PATCH] litedram: Make the L2 twice as tall This increases the number of L2 lines from 32 to 64. The BRAM usage is the same as they were only half used. There's an increase in LUTs and registers due to the extra tags and valid bits, but none of it should be in a space constrained or critical timing path. We could make it wider instead (256 bytes lines) which would reduce usage instead, but this increases the latency by 8 cycles. Something to consider once the L2 is capable of early response on miss and starting reloads from any point in a line. Signed-off-by: Benjamin Herrenschmidt --- litedram/extras/litedram-wrapper-l2.vhdl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/litedram/extras/litedram-wrapper-l2.vhdl b/litedram/extras/litedram-wrapper-l2.vhdl index 6bd3636..eb818ee 100644 --- a/litedram/extras/litedram-wrapper-l2.vhdl +++ b/litedram/extras/litedram-wrapper-l2.vhdl @@ -22,7 +22,7 @@ entity litedram_wrapper is -- Line size in bytes LINE_SIZE : positive := 128; -- Number of lines in a set - NUM_LINES : positive := 32; + NUM_LINES : positive := 64; -- Number of ways NUM_WAYS : positive := 4; -- Max number of stores in the queue