// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2020 MediaTek Inc. */ #include <linux/clk.h> #include <linux/interrupt.h> #include <linux/iopoll.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/of_device.h> #include <linux/of_irq.h> #include <linux/of_address.h> #define VIO_MOD_TO_REG_IND(m) ((m) / 32) #define VIO_MOD_TO_REG_OFF(m) ((m) % 32) struct mtk_devapc_vio_dbgs { union { u32 vio_dbg0; struct { u32 mstid:16; u32 dmnid:6; u32 vio_w:1; u32 vio_r:1; u32 addr_h:4; u32 resv:4; } dbg0_bits; }; u32 vio_dbg1; }; struct mtk_devapc_data { /* numbers of violation index */ u32 vio_idx_num; /* reg offset */ u32 vio_mask_offset; u32 vio_sta_offset; u32 vio_dbg0_offset; u32 vio_dbg1_offset; u32 apc_con_offset; u32 vio_shift_sta_offset; u32 vio_shift_sel_offset; u32 vio_shift_con_offset; }; struct mtk_devapc_context { struct device *dev; void __iomem *infra_base; struct clk *infra_clk; const struct mtk_devapc_data *data; }; static void clear_vio_status(struct mtk_devapc_context *ctx) { void __iomem *reg; int i; reg = ctx->infra_base + ctx->data->vio_sta_offset; for (i = 0; i < VIO_MOD_TO_REG_IND(ctx->data->vio_idx_num) - 1; i++) writel(GENMASK(31, 0), reg + 4 * i); writel(GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1, 0), reg + 4 * i); } static void mask_module_irq(struct mtk_devapc_context *ctx, bool mask) { void __iomem *reg; u32 val; int i; reg = ctx->infra_base + ctx->data->vio_mask_offset; if (mask) val = GENMASK(31, 0); else val = 0; for (i = 0; i < VIO_MOD_TO_REG_IND(ctx->data->vio_idx_num) - 1; i++) writel(val, reg + 4 * i); val = readl(reg + 4 * i); if (mask) val |= GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1, 0); else val &= ~GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1, 0); writel(val, reg + 4 * i); } #define PHY_DEVAPC_TIMEOUT 0x10000 /* * devapc_sync_vio_dbg - do "shift" mechansim" to get full violation information. * shift mechanism is depends on devapc hardware design. * Mediatek devapc set multiple slaves as a group. * When violation is triggered, violation info is kept * inside devapc hardware. * Driver should do shift mechansim to sync full violation * info to VIO_DBGs registers. * */ static int devapc_sync_vio_dbg(struct mtk_devapc_context *ctx) { void __iomem *pd_vio_shift_sta_reg; void __iomem *pd_vio_shift_sel_reg; void __iomem *pd_vio_shift_con_reg; int min_shift_group; int ret; u32 val; pd_vio_shift_sta_reg = ctx->infra_base + ctx->data->vio_shift_sta_offset; pd_vio_shift_sel_reg = ctx->infra_base + ctx->data->vio_shift_sel_offset; pd_vio_shift_con_reg = ctx->infra_base + ctx->data->vio_shift_con_offset; /* Find the minimum shift group which has violation */ val = readl(pd_vio_shift_sta_reg); if (!val) return false; min_shift_group = __ffs(val); /* Assign the group to sync */ writel(0x1 << min_shift_group, pd_vio_shift_sel_reg); /* Start syncing */ writel(0x1, pd_vio_shift_con_reg); ret = readl_poll_timeout(pd_vio_shift_con_reg, val, val == 0x3, 0, PHY_DEVAPC_TIMEOUT); if (ret) { dev_err(ctx->dev, "%s: Shift violation info failed\n", __func__); return false; } /* Stop syncing */ writel(0x0, pd_vio_shift_con_reg); /* Write clear */ writel(0x1 << min_shift_group, pd_vio_shift_sta_reg); return true; } /* * devapc_extract_vio_dbg - extract full violation information after doing * shift mechanism. */ static void devapc_extract_vio_dbg(struct mtk_devapc_context *ctx) { struct mtk_devapc_vio_dbgs vio_dbgs; void __iomem *vio_dbg0_reg; void __iomem *vio_dbg1_reg; vio_dbg0_reg = ctx->infra_base + ctx->data->vio_dbg0_offset; vio_dbg1_reg = ctx->infra_base + ctx->data->vio_dbg1_offset; vio_dbgs.vio_dbg0 = readl(vio_dbg0_reg); vio_dbgs.vio_dbg1 = readl(vio_dbg1_reg); /* Print violation information */ if (vio_dbgs.dbg0_bits.vio_w) dev_info(ctx->dev, "Write Violation\n"); else if (vio_dbgs.dbg0_bits.vio_r) dev_info(ctx->dev, "Read Violation\n"); dev_info(ctx->dev, "Bus ID:0x%x, Dom ID:0x%x, Vio Addr:0x%x\n", vio_dbgs.dbg0_bits.mstid, vio_dbgs.dbg0_bits.dmnid, vio_dbgs.vio_dbg1); } /* * devapc_violation_irq - the devapc Interrupt Service Routine (ISR) will dump * violation information including which master violates * access slave. */ static irqreturn_t devapc_violation_irq(int irq_number, void *data) { struct mtk_devapc_context *ctx = data; while (devapc_sync_vio_dbg(ctx)) devapc_extract_vio_dbg(ctx); clear_vio_status(ctx); return IRQ_HANDLED; } /* * start_devapc - unmask slave's irq to start receiving devapc violation. */ static void start_devapc(struct mtk_devapc_context *ctx) { writel(BIT(31), ctx->infra_base + ctx->data->apc_con_offset); mask_module_irq(ctx, false); } /* * stop_devapc - mask slave's irq to stop service. */ static void stop_devapc(struct mtk_devapc_context *ctx) { mask_module_irq(ctx, true); writel(BIT(2), ctx->infra_base + ctx->data->apc_con_offset); } static const struct mtk_devapc_data devapc_mt6779 = { .vio_idx_num = 511, .vio_mask_offset = 0x0, .vio_sta_offset = 0x400, .vio_dbg0_offset = 0x900, .vio_dbg1_offset = 0x904, .apc_con_offset = 0xF00, .vio_shift_sta_offset = 0xF10, .vio_shift_sel_offset = 0xF14, .vio_shift_con_offset = 0xF20, }; static const struct of_device_id mtk_devapc_dt_match[] = { { .compatible = "mediatek,mt6779-devapc", .data = &devapc_mt6779, }, { }, }; MODULE_DEVICE_TABLE(of, mtk_devapc_dt_match); static int mtk_devapc_probe(struct platform_device *pdev) { struct device_node *node = pdev->dev.of_node; struct mtk_devapc_context *ctx; u32 devapc_irq; int ret; if (IS_ERR(node)) return -ENODEV; ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); if (!ctx) return -ENOMEM; ctx->data = of_device_get_match_data(&pdev->dev); ctx->dev = &pdev->dev; ctx->infra_base = of_iomap(node, 0); if (!ctx->infra_base) return -EINVAL; devapc_irq = irq_of_parse_and_map(node, 0); if (!devapc_irq) return -EINVAL; ctx->infra_clk = devm_clk_get(&pdev->dev, "devapc-infra-clock"); if (IS_ERR(ctx->infra_clk)) return -EINVAL; if (clk_prepare_enable(ctx->infra_clk)) return -EINVAL; ret = devm_request_irq(&pdev->dev, devapc_irq, devapc_violation_irq, IRQF_TRIGGER_NONE, "devapc", ctx); if (ret) { clk_disable_unprepare(ctx->infra_clk); return ret; } platform_set_drvdata(pdev, ctx); start_devapc(ctx); return 0; } static int mtk_devapc_remove(struct platform_device *pdev) { struct mtk_devapc_context *ctx = platform_get_drvdata(pdev); stop_devapc(ctx); clk_disable_unprepare(ctx->infra_clk); return 0; } static struct platform_driver mtk_devapc_driver = { .probe = mtk_devapc_probe, .remove = mtk_devapc_remove, .driver = { .name = "mtk-devapc", .of_match_table = mtk_devapc_dt_match, }, }; module_platform_driver(mtk_devapc_driver); MODULE_DESCRIPTION("Mediatek Device APC Driver"); MODULE_AUTHOR("Neal Liu <neal.liu@mediatek.com>"); MODULE_LICENSE("GPL");