// SPDX-License-Identifier: GPL-2.0 /* * SDK7786 FPGA SRAM Support. * * Copyright (C) 2010 Paul Mundt */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> #include <linux/kernel.h> #include <linux/types.h> #include <linux/io.h> #include <linux/string.h> #include <mach/fpga.h> #include <asm/sram.h> #include <linux/sizes.h> static int __init fpga_sram_init(void) { unsigned long phys; unsigned int area; void __iomem *vaddr; int ret; u16 data; /* Enable FPGA SRAM */ data = fpga_read_reg(LCLASR); data |= LCLASR_FRAMEN; fpga_write_reg(data, LCLASR); /* * FPGA_SEL determines the area mapping */ area = (data & LCLASR_FPGA_SEL_MASK) >> LCLASR_FPGA_SEL_SHIFT; if (unlikely(area == LCLASR_AREA_MASK)) { pr_err("FPGA memory unmapped.\n"); return -ENXIO; } /* * The memory itself occupies a 2KiB range at the top of the area * immediately below the system registers. */ phys = (area << 26) + SZ_64M - SZ_4K; /* * The FPGA SRAM resides in translatable physical space, so set * up a mapping prior to inserting it in to the pool. */ vaddr = ioremap(phys, SZ_2K); if (unlikely(!vaddr)) { pr_err("Failed remapping FPGA memory.\n"); return -ENXIO; } pr_info("Adding %dKiB of FPGA memory at 0x%08lx-0x%08lx " "(area %d) to pool.\n", SZ_2K >> 10, phys, phys + SZ_2K - 1, area); ret = gen_pool_add(sram_pool, (unsigned long)vaddr, SZ_2K, -1); if (unlikely(ret < 0)) { pr_err("Failed adding memory\n"); iounmap(vaddr); return ret; } return 0; } postcore_initcall(fpga_sram_init);