Re: [PATCH 04/16] remoteproc/pru: Add PRU remoteproc driver

From: Dimitar Dimitrov
Date: Fri Nov 30 2018 - 16:39:55 EST


On Monday, 12/26/2018, 9:52:37 EET Roger Quadros wrote:
> +/*
> + * Convert PRU device address (instruction space) to kernel virtual address
> + *
> + * A PRU does not have an unified address space. Each PRU has its very own
> + * private Instruction RAM, and its device address is identical to that of
> + * its primary Data RAM device address.
> + */
> +static void *pru_i_da_to_va(struct pru_rproc *pru, u32 da, int len)
> +{
> + u32 offset;
> + void *va = NULL;
> +
> + if (len <= 0)
> + return NULL;

Could you please clear the upper 4 bits the of IRAM device address, in order
to support binutils ELF images? Here is an example line to add here:

+ /* GNU binutils do not support multiple address spaces. The
+ * default linker script from the official GNU pru-ld places
+ * IRAM at an arbitrary high offset, in order to differentiate it
+ * from DRAM. Hence we need to strip the artificial offset
+ * from the IRAM address.
+ */
+ da &= ~0xf0000000u;
+


> +
> + if (da >= pru->iram_da &&
> + da + len <= pru->iram_da + pru->mem_regions[PRU_MEM_IRAM].size {
> + offset = da - pru->iram_da;
> + va = (__force void *)(pru->mem_regions[PRU_MEM_IRAM].va +
> + offset);
> + }
> +
> + return va;
> +}