/* * Memory controller driver for ARM PrimeCell PL172 * PrimeCell MultiPort Memory Controller (PL172) * * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com> * * Based on: * TI AEMIF driver, Copyright (C) 2010 - 2013 Texas Instruments Inc. * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/amba/bus.h> #include <linux/clk.h> #include <linux/device.h> #include <linux/err.h> #include <linux/init.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_platform.h> #include <linux/time.h> #define MPMC_STATIC_CFG(n) (0x200 + 0x20 * n) #define MPMC_STATIC_CFG_MW_8BIT 0x0 #define MPMC_STATIC_CFG_MW_16BIT 0x1 #define MPMC_STATIC_CFG_MW_32BIT 0x2 #define MPMC_STATIC_CFG_PM BIT(3) #define MPMC_STATIC_CFG_PC BIT(6) #define MPMC_STATIC_CFG_PB BIT(7) #define MPMC_STATIC_CFG_EW BIT(8) #define MPMC_STATIC_CFG_B BIT(19) #define MPMC_STATIC_CFG_P BIT(20) #define MPMC_STATIC_WAIT_WEN(n) (0x204 + 0x20 * n) #define MPMC_STATIC_WAIT_WEN_MAX 0x0f #define MPMC_STATIC_WAIT_OEN(n) (0x208 + 0x20 * n) #define MPMC_STATIC_WAIT_OEN_MAX 0x0f #define MPMC_STATIC_WAIT_RD(n) (0x20c + 0x20 * n) #define MPMC_STATIC_WAIT_RD_MAX 0x1f #define MPMC_STATIC_WAIT_PAGE(n) (0x210 + 0x20 * n) #define MPMC_STATIC_WAIT_PAGE_MAX 0x1f #define MPMC_STATIC_WAIT_WR(n) (0x214 + 0x20 * n) #define MPMC_STATIC_WAIT_WR_MAX 0x1f #define MPMC_STATIC_WAIT_TURN(n) (0x218 + 0x20 * n) #define MPMC_STATIC_WAIT_TURN_MAX 0x0f /* Maximum number of static chip selects */ #define PL172_MAX_CS 4 struct pl172_data { void __iomem *base; unsigned long rate; struct clk *clk; }; static int pl172_timing_prop(struct amba_device *adev, const struct device_node *np, const char *name, u32 reg_offset, u32 max, int start) { struct pl172_data *pl172 = amba_get_drvdata(adev); int cycles; u32 val; if (!of_property_read_u32(np, name, &val)) { cycles = DIV_ROUND_UP(val * pl172->rate, NSEC_PER_MSEC) - start; if (cycles < 0) { cycles = 0; } else if (cycles > max) { dev_err(&adev->dev, "%s timing too tight\n", name); return -EINVAL; } writel(cycles, pl172->base + reg_offset); } dev_dbg(&adev->dev, "%s: %u cycle(s)\n", name, start + readl(pl172->base + reg_offset)); return 0; } static int pl172_setup_static(struct amba_device *adev, struct device_node *np, u32 cs) { struct pl172_data *pl172 = amba_get_drvdata(adev); u32 cfg; int ret; /* MPMC static memory configuration */ if (!of_property_read_u32(np, "mpmc,memory-width", &cfg)) { if (cfg == 8) { cfg = MPMC_STATIC_CFG_MW_8BIT; } else if (cfg == 16) { cfg = MPMC_STATIC_CFG_MW_16BIT; } else if (cfg == 32) { cfg = MPMC_STATIC_CFG_MW_32BIT; } else { dev_err(&adev->dev, "invalid memory width cs%u\n", cs); return -EINVAL; } } else { dev_err(&adev->dev, "memory-width property required\n"); return -EINVAL; } if (of_property_read_bool(np, "mpmc,async-page-mode")) cfg |= MPMC_STATIC_CFG_PM; if (of_property_read_bool(np, "mpmc,cs-active-high")) cfg |= MPMC_STATIC_CFG_PC; if (of_property_read_bool(np, "mpmc,byte-lane-low")) cfg |= MPMC_STATIC_CFG_PB; if (of_property_read_bool(np, "mpmc,extended-wait")) cfg |= MPMC_STATIC_CFG_EW; if (amba_part(adev) == 0x172 && of_property_read_bool(np, "mpmc,buffer-enable")) cfg |= MPMC_STATIC_CFG_B; if (of_property_read_bool(np, "mpmc,write-protect")) cfg |= MPMC_STATIC_CFG_P; writel(cfg, pl172->base + MPMC_STATIC_CFG(cs)); dev_dbg(&adev->dev, "mpmc static config cs%u: 0x%08x\n", cs, cfg); /* MPMC static memory timing */ ret = pl172_timing_prop(adev, np, "mpmc,write-enable-delay", MPMC_STATIC_WAIT_WEN(cs), MPMC_STATIC_WAIT_WEN_MAX, 1); if (ret) goto fail; ret = pl172_timing_prop(adev, np, "mpmc,output-enable-delay", MPMC_STATIC_WAIT_OEN(cs), MPMC_STATIC_WAIT_OEN_MAX, 0); if (ret) goto fail; ret = pl172_timing_prop(adev, np, "mpmc,read-access-delay", MPMC_STATIC_WAIT_RD(cs), MPMC_STATIC_WAIT_RD_MAX, 1); if (ret) goto fail; ret = pl172_timing_prop(adev, np, "mpmc,page-mode-read-delay", MPMC_STATIC_WAIT_PAGE(cs), MPMC_STATIC_WAIT_PAGE_MAX, 1); if (ret) goto fail; ret = pl172_timing_prop(adev, np, "mpmc,write-access-delay", MPMC_STATIC_WAIT_WR(cs), MPMC_STATIC_WAIT_WR_MAX, 2); if (ret) goto fail; ret = pl172_timing_prop(adev, np, "mpmc,turn-round-delay", MPMC_STATIC_WAIT_TURN(cs), MPMC_STATIC_WAIT_TURN_MAX, 1); if (ret) goto fail; return 0; fail: dev_err(&adev->dev, "failed to configure cs%u\n", cs); return ret; } static int pl172_parse_cs_config(struct amba_device *adev, struct device_node *np) { u32 cs; if (!of_property_read_u32(np, "mpmc,cs", &cs)) { if (cs >= PL172_MAX_CS) { dev_err(&adev->dev, "cs%u invalid\n", cs); return -EINVAL; } return pl172_setup_static(adev, np, cs); } dev_err(&adev->dev, "cs property required\n"); return -EINVAL; } static const char * const pl172_revisions[] = {"r1", "r2", "r2p3", "r2p4"}; static const char * const pl175_revisions[] = {"r1"}; static const char * const pl176_revisions[] = {"r0"}; static int pl172_probe(struct amba_device *adev, const struct amba_id *id) { struct device_node *child_np, *np = adev->dev.of_node; struct device *dev = &adev->dev; static const char *rev = "?"; struct pl172_data *pl172; int ret; if (amba_part(adev) == 0x172) { if (amba_rev(adev) < ARRAY_SIZE(pl172_revisions)) rev = pl172_revisions[amba_rev(adev)]; } else if (amba_part(adev) == 0x175) { if (amba_rev(adev) < ARRAY_SIZE(pl175_revisions)) rev = pl175_revisions[amba_rev(adev)]; } else if (amba_part(adev) == 0x176) { if (amba_rev(adev) < ARRAY_SIZE(pl176_revisions)) rev = pl176_revisions[amba_rev(adev)]; } dev_info(dev, "ARM PL%x revision %s\n", amba_part(adev), rev); pl172 = devm_kzalloc(dev, sizeof(*pl172), GFP_KERNEL); if (!pl172) return -ENOMEM; pl172->clk = devm_clk_get(dev, "mpmcclk"); if (IS_ERR(pl172->clk)) { dev_err(dev, "no mpmcclk provided clock\n"); return PTR_ERR(pl172->clk); } ret = clk_prepare_enable(pl172->clk); if (ret) { dev_err(dev, "unable to mpmcclk enable clock\n"); return ret; } pl172->rate = clk_get_rate(pl172->clk) / MSEC_PER_SEC; if (!pl172->rate) { dev_err(dev, "unable to get mpmcclk clock rate\n"); ret = -EINVAL; goto err_clk_enable; } ret = amba_request_regions(adev, NULL); if (ret) { dev_err(dev, "unable to request AMBA regions\n"); goto err_clk_enable; } pl172->base = devm_ioremap(dev, adev->res.start, resource_size(&adev->res)); if (!pl172->base) { dev_err(dev, "ioremap failed\n"); ret = -ENOMEM; goto err_no_ioremap; } amba_set_drvdata(adev, pl172); /* * Loop through each child node, which represent a chip select, and * configure parameters and timing. If successful; populate devices * under that node. */ for_each_available_child_of_node(np, child_np) { ret = pl172_parse_cs_config(adev, child_np); if (ret) continue; of_platform_populate(child_np, NULL, NULL, dev); } return 0; err_no_ioremap: amba_release_regions(adev); err_clk_enable: clk_disable_unprepare(pl172->clk); return ret; } static int pl172_remove(struct amba_device *adev) { struct pl172_data *pl172 = amba_get_drvdata(adev); clk_disable_unprepare(pl172->clk); amba_release_regions(adev); return 0; } static const struct amba_id pl172_ids[] = { /* PrimeCell MPMC PL172, EMC found on NXP LPC18xx and LPC43xx */ { .id = 0x07041172, .mask = 0x3f0fffff, }, /* PrimeCell MPMC PL175, EMC found on NXP LPC32xx */ { .id = 0x07041175, .mask = 0x3f0fffff, }, /* PrimeCell MPMC PL176 */ { .id = 0x89041176, .mask = 0xff0fffff, }, { 0, 0 }, }; MODULE_DEVICE_TABLE(amba, pl172_ids); static struct amba_driver pl172_driver = { .drv = { .name = "memory-pl172", }, .probe = pl172_probe, .remove = pl172_remove, .id_table = pl172_ids, }; module_amba_driver(pl172_driver); MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>"); MODULE_DESCRIPTION("PL172 Memory Controller Driver"); MODULE_LICENSE("GPL v2");