net: mvpp2: handle register mapping and access for PPv2.2
This commit adjusts the mvpp2 driver register mapping and access logic to support PPv2.2, to handle a number of differences. Due to how the registers are laid out in memory, the Device Tree binding for the "reg" property is different: - On PPv2.1, we had a first area for the packet processor registers (common to all ports), and then one area per port. - On PPv2.2, we have a first area for the packet processor registers (common to all ports), and a second area for numerous other registers, including a large number of per-port registers In addition, on PPv2.2, the area for the common registers is split into so-called "address spaces" of 64 KB each. They allow to access per-CPU registers, where each CPU has its own copy of some registers. A few other registers, which have a single copy, also need to be accessed from those per-CPU windows if they are related to a per-CPU register. For example: - Writing to MVPP2_TXQ_NUM_REG selects a TX queue. This register is a per-CPU register, it must be accessed from the current CPU register window. - Then a write to MVPP2_TXQ_PENDING_REG, MVPP2_TXQ_DESC_ADDR_REG (and a few others) will affect the TX queue that was selected by the write to MVPP2_TXQ_NUM_REG. It must be accessed from the same CPU window as the write to the TXQ_NUM_REG. Therefore, the ->base member of 'struct mvpp2' is replaced with a ->cpu_base[] array, each entry pointing to a mapping of the per-CPU area. Since PPv2.1 doesn't have this concept of per-CPU windows, all entries in ->cpu_base[] point to the same io-remapped area. The existing mvpp2_read() and mvpp2_write() accessors use cpu_base[0], they are used for registers for which the CPU window doesn't matter. mvpp2_percpu_read() and mvpp2_percpu_write() are new accessors added to access the registers for which the CPU window does matter, which is why they take a "cpu" as argument. The driver is then changed to use mvpp2_percpu_read() and mvpp2_percpu_write() where it matters. Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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