PCIe TLP write packet address only 31:2 bits
Let's take a sample write packet : Suppose that the CPU wrote the value
0x12345678to the physical address0xfdaff040using 32-bit addressing
This example is from this site (I didn't understand the explanations in the original post)
- Why does the address start at the second bit
[31 : 2] - Why isn't the address the same
Solution
An address of an aligned, 32-bit chunk always has two zero bits at the end of the address. You can think of this as either writing the address of the chunk to the 32-bit slot or as writing the addresses divided by four to bits 2 through 31 of the address. The result is the same either way since dividing by four is equivalent to shifting two bit positions to the right.
- what is the purpose of using index caches in rigtorp's SPSCQueue
- What does it mean by word size in computer?
- How is cache coherency maintained on ARMv8 big.LITTLE system?
- FLOPs per cycle for Sandy Bridge and Haswell and others SSE2 / AVX / AVX2 / AVX-512
- How can I implement the overflow flag in Logisim without having access to the second last carry?
- Difference between x86, x32, and x64 architectures?
- The most efficient way to test if a positive integer is 2^n (i.e. 1, 2, 4, 8, etc.) in C++20?
- What is the cost of atomic operations?
- How can the control hardware know which registers to read before it completes decoding the instruction?
- Microarchitectural zeroing of a register via the register renamer: performance versus a mov?
- Why do I get 'Error executing binary file' despite compiling for the correct architecture?
- Hardware interrupt when Power Button pressed?
- Program Counter incrementation
- Why is processing a sorted array faster than processing an unsorted array?
- Is lock acquiring function atomic?
- Understanding micro-architectural causes for longer code to execute 4x faster (AMD Zen 2 architecture)
- when we say a memory controller does it mean the component that manages communication between the RAM and the processor only?
- In shift left instruction, why is rt used as source register instead of rs?
- Intel vs AMD gather AVX performance
- In a RISC-V architecture, do jump instructions (conditional or JAL/JALR) increase the PC by 4 as the rest of the instructions?
- Why is memory aliasing needed?
- Understanding LW in MIPS
- How can x86 bsr/bsf have fixed latency, not data dependent? Doesn't it loop over bits like the pseudocode shows?
- Getting docker-entrypoint.sh: exec format error while the architecture matches
- Implementing closures and performance impacts of, for instance, relative vs absolute jump
- Are data memory and instruction memory in data path L1 caches?
- How does gem decide, which arch-specific gem to install?
- Why is the size of L1 cache smaller than that of the L2 cache in most of the processors?
- PCIe TLP write packet address only 31:2 bits
- Determine target ISA extensions of binary file in Linux (library or executable)