From 556eded0923f449e56b2b71cbc8f6fa668c87a07 Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Sun, 28 Jun 2020 10:14:36 +0100 Subject: [PATCH] attempt to get Pi2LSUI FSM working --- src/soc/experiment/pi2ls.py | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/src/soc/experiment/pi2ls.py b/src/soc/experiment/pi2ls.py index 9356b912..32b9693d 100644 --- a/src/soc/experiment/pi2ls.py +++ b/src/soc/experiment/pi2ls.py @@ -58,29 +58,35 @@ class Pi2LSUI(Elaboratable): m.submodules.lenexp = lenexp = LenExpand(log2_int(self.addrbits), 8) ld_in_progress = Signal(reset=0) + st_in_progress = Signal(reset=0) m.d.comb += lsui.x_ld_i.eq(pi.is_ld_i) m.d.comb += lsui.x_st_i.eq(pi.is_st_i) - m.d.comb += pi.busy_o.eq(lsui.x_busy_o) + m.d.comb += pi.busy_o.eq(pi.is_ld_i | pi.is_st_i)#lsui.x_busy_o) + + lsbaddr, msbaddr = self.splitaddr(pi.addr.data) + m.d.comb += lenexp.len_i.eq(pi.data_len) + m.d.comb += lenexp.addr_i.eq(lsbaddr) # LSBs of addr + m.d.comb += lsui.x_addr_i.eq(pi.addr.data) # XXX hmmm... with m.If(pi.addr.ok): # expand the LSBs of address plus LD/ST len into 16-bit mask - lsbaddr, msbaddr = self.splitaddr(pi.addr.data) - m.d.comb += lenexp.len_i.eq(pi.data_len) - m.d.comb += lenexp.addr_i.eq(lsbaddr) # LSBs of addr m.d.comb += lsui.x_mask_i.eq(lenexp.lexp_o) # pass through the address, indicate "valid" - m.d.comb += lsui.x_addr_i.eq(pi.addr.data) # XXX hmmm... m.d.comb += lsui.x_valid_i.eq(1) # indicate "OK" - XXX should be checking address valid m.d.comb += pi.addr_ok_o.eq(1) - with m.If(pi.is_ld_i & pi.addr.ok): + with m.If(~lsui.x_busy_o & pi.is_st_i & pi.addr.ok): + m.d.sync += st_in_progress.eq(1) + + with m.If(pi.is_ld_i): # shift/mask out the loaded data m.d.comb += pi.ld.data.eq((lsui.m_ld_data_o & lenexp.rexp_o) >> (lenexp.addr_i*8)) # remember we're in the process of loading - m.d.sync += ld_in_progress.eq(1) + with m.If(pi.addr.ok): + m.d.sync += ld_in_progress.eq(1) # If a load happened on the previous cycle and the memory is # not busy, that means it returned the data from the load. In @@ -94,5 +100,9 @@ class Pi2LSUI(Elaboratable): with m.If(pi.is_st_i & pi.st.ok): m.d.comb += lsui.x_st_data_i.eq(pi.st.data << (lenexp.addr_i*8)) + with m.If(st_in_progress): + m.d.sync += st_in_progress.eq(0) + with m.Else(): + m.d.comb += pi.busy_o.eq(0) return m -- 2.30.2