On Tuesday, November 22, 2016 5:48:41 PM CET Gregory CLEMENT wrote:
> +#ifdef CONFIG_64BIT
> + void *data_tmp;
> +
> + /* In Neta HW only 32 bits data is supported, so in order to
> + * obtain whole 64 bits address from RX descriptor, we store
> + * the upper 32 bits when allocating buffer, and put it back
> + * when using buffer cookie for accessing packet in memory.
> + * Frags should be allocated from single 'memory' region,
> + * hence common upper address half should be sufficient.
> + */
> + data_tmp = mvneta_frag_alloc(pp->frag_size);
> + if (data_tmp) {
> + pp->data_high = (u64)upper_32_bits((u64)data_tmp) << 32;
> + mvneta_frag_free(pp->frag_size, data_tmp);
> + }
>
How does this work when the region spans a n*4GB address boundary?
Arnd
