i40e: draft for hmc fetch for direct access

i40e_bm/i40e_bm.h

@@ -130,7 +130,7 @@ class host_mem_cache {
         static const uint16_t MAX_SEGMENTS = 0x1000;
 
         struct segment {
-            uint64_t pdir_addr;
+            uint64_t addr;
             uint16_t pgcount;
             bool valid;
             bool direct;
@@ -138,9 +138,18 @@ class host_mem_cache {
 
         i40e_bm &dev;
         segment segs[MAX_SEGMENTS];
+
     public:
+        class mem_op : public dma_base {
+            public:
+                bool failed;
+        };
+
         host_mem_cache(i40e_bm &dev);
         void reg_updated(uint64_t addr);
+
+        // issue a hmc memory operation (address is in the context
+        void issue_mem_op(mem_op &op);
 };
 
 

i40e_bm/i40e_hmc.cc

@@ -15,7 +15,7 @@ host_mem_cache::host_mem_cache(i40e_bm &dev_)
     : dev(dev_)
 {
     for (size_t i = 0; i < MAX_SEGMENTS; i++) {
-        segs[i].pdir_addr = 0;
+        segs[i].addr = 0;
         segs[i].pgcount = 0;
         segs[i].valid = false;
         segs[i].direct = false;
@@ -24,5 +24,86 @@ host_mem_cache::host_mem_cache(i40e_bm &dev_)
 
 void host_mem_cache::reg_updated(uint64_t addr)
 {
-    std::cerr << "hmc reg updated " << addr << std::endl;
+    if (addr == I40E_PFHMC_SDCMD) {
+        // read/write command for descriptor
+        uint32_t cmd = dev.regs.pfhmc_sdcmd;
+        uint16_t idx = (cmd & I40E_PFHMC_SDCMD_PMSDIDX_MASK) >>
+            I40E_PFHMC_SDCMD_PMSDIDX_SHIFT;
+
+        uint32_t lo = dev.regs.pfhmc_sddatalow;
+        uint32_t hi = dev.regs.pfhmc_sddatahigh;
+        if ((cmd & I40E_PFHMC_SDCMD_PMSDWR_MASK)) {
+            // write
+            std::cerr << "hmc: writing descriptor " << idx << std::endl;
+
+            segs[idx].addr = ((lo & I40E_PFHMC_SDDATALOW_PMSDDATALOW_MASK) >>
+                I40E_PFHMC_SDDATALOW_PMSDDATALOW_SHIFT) << 12;
+            segs[idx].addr |= ((uint64_t) hi) << 32;
+            segs[idx].pgcount = (lo & I40E_PFHMC_SDDATALOW_PMSDBPCOUNT_MASK) >>
+                I40E_PFHMC_SDDATALOW_PMSDBPCOUNT_SHIFT;
+            segs[idx].valid = !!(lo & I40E_PFHMC_SDDATALOW_PMSDVALID_MASK);
+            segs[idx].direct = !!(lo & I40E_PFHMC_SDDATALOW_PMSDTYPE_MASK);
+
+            std::cerr << "    addr=" << segs[idx].addr << " pgcount=" <<
+                segs[idx].pgcount << " valid=" << segs[idx].valid <<
+                " direct=" << segs[idx].direct << std::endl;
+        } else {
+            // read
+            std::cerr << "hmc: reading descriptor " << idx << std::endl;
+
+            dev.regs.pfhmc_sddatalow = ((segs[idx].addr >> 12) <<
+                    I40E_PFHMC_SDDATALOW_PMSDDATALOW_SHIFT) &
+                I40E_PFHMC_SDDATALOW_PMSDDATALOW_MASK;
+            dev.regs.pfhmc_sddatalow |= (segs[idx].pgcount <<
+                    I40E_PFHMC_SDDATALOW_PMSDBPCOUNT_SHIFT) &
+                I40E_PFHMC_SDDATALOW_PMSDBPCOUNT_MASK;
+            if (segs[idx].valid)
+                dev.regs.pfhmc_sddatalow |= I40E_PFHMC_SDDATALOW_PMSDVALID_MASK;
+            if (segs[idx].direct)
+                dev.regs.pfhmc_sddatalow |= I40E_PFHMC_SDDATALOW_PMSDTYPE_MASK;
+            dev.regs.pfhmc_sddatahigh = segs[idx].addr >> 32;
+        }
+    }
+}
+
+void host_mem_cache::issue_mem_op(mem_op &op)
+{
+    uint64_t addr = op.dma_addr;
+    uint16_t seg_idx = addr >> 21;
+    uint16_t seg_idx_last = (addr + op.len - 1) >> 21;
+    uint32_t dir_off = addr & ((1 << 21) - 1);
+    struct segment *seg = &segs[seg_idx];
+
+    if (seg_idx >= MAX_SEGMENTS) {
+        std::cerr << "hmc issue_mem_op: seg index too high " << seg_idx <<
+            std::endl;
+        abort();
+    }
+
+    if (!seg->valid) {
+        // TODO: errorinfo and data registers
+        std::cerr << "hmc issue_mem_op: segment invalid addr=" << addr <<
+            std::endl;
+        op.failed = true;
+        return;
+    }
+
+    if (seg_idx != seg_idx_last) {
+        std::cerr << "hmc issue_mem_op: operation crosses segs addr=" <<
+            addr << " len=" << op.len << std::endl;
+        abort();
+    }
+
+    if (!seg->direct) {
+        std::cerr << "hmc issue_mem_op: TODO paged ops addr=" << addr <<
+            std::endl;
+        abort();
+    }
+
+    op.failed = false;
+    op.dma_addr = seg->addr + dir_off;
+
+    std::cerr << "hmc issue_mem_op: hmc_addr=" << addr << " dma_addr=" <<
+        op.dma_addr << " len=" << op.len << std::endl;
+    runner->issue_dma(op);
 }