From b34ea31fe013569d42b7e8681ef3f717f77c5b72 Mon Sep 17 00:00:00 2001 From: Dafna Hirschfeld Date: Fri, 16 Apr 2021 12:54:49 +0200 Subject: [PATCH] iommu/mediatek: Always enable the clk on resume In mtk_iommu_runtime_resume always enable the clk, even if m4u_dom is null. Otherwise the 'suspend' cb might disable the clk which is already disabled causing the warning: [ 1.586104] infra_m4u already disabled [ 1.586133] WARNING: CPU: 0 PID: 121 at drivers/clk/clk.c:952 clk_core_disable+0xb0/0xb8 [ 1.594391] mtk-iommu 10205000.iommu: bound 18001000.larb (ops mtk_smi_larb_component_ops) [ 1.598108] Modules linked in: [ 1.598114] CPU: 0 PID: 121 Comm: kworker/0:2 Not tainted 5.12.0-rc5 #69 [ 1.609246] mtk-iommu 10205000.iommu: bound 14027000.larb (ops mtk_smi_larb_component_ops) [ 1.617487] Hardware name: Google Elm (DT) [ 1.617491] Workqueue: pm pm_runtime_work [ 1.620545] mtk-iommu 10205000.iommu: bound 19001000.larb (ops mtk_smi_larb_component_ops) [ 1.627229] pstate: 60000085 (nZCv daIf -PAN -UAO -TCO BTYPE=--) [ 1.659297] pc : clk_core_disable+0xb0/0xb8 [ 1.663475] lr : clk_core_disable+0xb0/0xb8 [ 1.667652] sp : ffff800011b9bbe0 [ 1.670959] x29: ffff800011b9bbe0 x28: 0000000000000000 [ 1.676267] x27: ffff800011448000 x26: ffff8000100cfd98 [ 1.681574] x25: ffff800011b9bd48 x24: 0000000000000000 [ 1.686882] x23: 0000000000000000 x22: ffff8000106fad90 [ 1.692189] x21: 000000000000000a x20: ffff0000c0048500 [ 1.697496] x19: ffff0000c0048500 x18: ffffffffffffffff [ 1.702804] x17: 0000000000000000 x16: 0000000000000000 [ 1.708112] x15: ffff800011460300 x14: fffffffffffe0000 [ 1.713420] x13: ffff8000114602d8 x12: 0720072007200720 [ 1.718727] x11: 0720072007200720 x10: 0720072007200720 [ 1.724035] x9 : ffff800011b9bbe0 x8 : ffff800011b9bbe0 [ 1.729342] x7 : 0000000000000009 x6 : ffff8000114b8328 [ 1.734649] x5 : 0000000000000000 x4 : 0000000000000000 [ 1.739956] x3 : 00000000ffffffff x2 : ffff800011460298 [ 1.745263] x1 : 1af1d7de276f4500 x0 : 0000000000000000 [ 1.750572] Call trace: [ 1.753010] clk_core_disable+0xb0/0xb8 [ 1.756840] clk_core_disable_lock+0x24/0x40 [ 1.761105] clk_disable+0x20/0x30 [ 1.764501] mtk_iommu_runtime_suspend+0x88/0xa8 [ 1.769114] pm_generic_runtime_suspend+0x2c/0x48 [ 1.773815] __rpm_callback+0xe0/0x178 [ 1.777559] rpm_callback+0x24/0x88 [ 1.781041] rpm_suspend+0xdc/0x470 [ 1.784523] rpm_idle+0x12c/0x170 [ 1.787831] pm_runtime_work+0xa8/0xc0 [ 1.791573] process_one_work+0x1e8/0x360 [ 1.795580] worker_thread+0x44/0x478 [ 1.799237] kthread+0x150/0x158 [ 1.802460] ret_from_fork+0x10/0x30 [ 1.806034] ---[ end trace 82402920ef64573b ]--- [ 1.810728] ------------[ cut here ]------------ In addition, we now don't need to enable the clock from the function mtk_iommu_hw_init since it is already enabled by the resume. Fixes: c0b57581b73b ("iommu/mediatek: Add power-domain operation") Signed-off-by: Dafna Hirschfeld Reviewed-by: Yong Wu Link: https://lore.kernel.org/r/20210416105449.4744-1-dafna.hirschfeld@collabora.com Signed-off-by: Joerg Roedel --- drivers/iommu/mtk_iommu.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 7537593..cdda3a8 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -690,13 +690,6 @@ static const struct iommu_ops mtk_iommu_ops = { static int mtk_iommu_hw_init(const struct mtk_iommu_data *data) { u32 regval; - int ret; - - ret = clk_prepare_enable(data->bclk); - if (ret) { - dev_err(data->dev, "Failed to enable iommu bclk(%d)\n", ret); - return ret; - } if (data->plat_data->m4u_plat == M4U_MT8173) { regval = F_MMU_PREFETCH_RT_REPLACE_MOD | @@ -762,7 +755,6 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data) if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0, dev_name(data->dev), (void *)data)) { writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR); - clk_disable_unprepare(data->bclk); dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq); return -ENODEV; } @@ -979,14 +971,19 @@ static int __maybe_unused mtk_iommu_runtime_resume(struct device *dev) void __iomem *base = data->base; int ret; - /* Avoid first resume to affect the default value of registers below. */ - if (!m4u_dom) - return 0; ret = clk_prepare_enable(data->bclk); if (ret) { dev_err(data->dev, "Failed to enable clk(%d) in resume\n", ret); return ret; } + + /* + * Uppon first resume, only enable the clk and return, since the values of the + * registers are not yet set. + */ + if (!m4u_dom) + return 0; + writel_relaxed(reg->wr_len_ctrl, base + REG_MMU_WR_LEN_CTRL); writel_relaxed(reg->misc_ctrl, base + REG_MMU_MISC_CTRL); writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM_DIS); -- 2.7.4