From 53a61badf47e674fb43d73cd22f0f8065098ddf6 Mon Sep 17 00:00:00 2001 From: "Koul, Vinod" Date: Mon, 4 Oct 2010 10:42:40 +0000 Subject: [PATCH] intel_mid_dma: Add runtime PM support This patch adds runtime PM support in this dma driver for 4 PCI Controllers Whenever the driver is idle (no channels grabbed), it can go to low power state It also adds the PCI suspend and resume support Signed-off-by: Vinod Koul Signed-off-by: Alan Cox Signed-off-by: Dan Williams --- drivers/dma/intel_mid_dma.c | 123 +++++++++++++++++++++++++++++-- drivers/dma/intel_mid_dma_regs.h | 14 +++- 2 files changed, 129 insertions(+), 8 deletions(-) diff --git a/drivers/dma/intel_mid_dma.c b/drivers/dma/intel_mid_dma.c index c2591e8d9b6e..373396c462a0 100644 --- a/drivers/dma/intel_mid_dma.c +++ b/drivers/dma/intel_mid_dma.c @@ -25,6 +25,7 @@ */ #include #include +#include #include #define MAX_CHAN 4 /*max ch across controllers*/ @@ -247,13 +248,13 @@ static void midc_dostart(struct intel_mid_dma_chan *midc, struct middma_device *mid = to_middma_device(midc->chan.device); /* channel is idle */ - if (midc->in_use && test_ch_en(midc->dma_base, midc->ch_id)) { + if (midc->busy && test_ch_en(midc->dma_base, midc->ch_id)) { /*error*/ pr_err("ERR_MDMA: channel is busy in start\n"); /* The tasklet will hopefully advance the queue... */ return; } - + midc->busy = true; /*write registers and en*/ iowrite32(first->sar, midc->ch_regs + SAR); iowrite32(first->dar, midc->ch_regs + DAR); @@ -290,7 +291,7 @@ static void midc_descriptor_complete(struct intel_mid_dma_chan *midc, param_txd = txd->callback_param; list_move(&desc->desc_node, &midc->free_list); - + midc->busy = false; spin_unlock_bh(&midc->lock); if (callback_txd) { pr_debug("MDMA: TXD callback set ... calling\n"); @@ -434,7 +435,7 @@ static int intel_mid_dma_device_control(struct dma_chan *chan, return -ENXIO; spin_lock_bh(&midc->lock); - if (midc->in_use == false) { + if (midc->busy == false) { spin_unlock_bh(&midc->lock); return 0; } @@ -618,11 +619,11 @@ static void intel_mid_dma_free_chan_resources(struct dma_chan *chan) struct middma_device *mid = to_middma_device(chan->device); struct intel_mid_dma_desc *desc, *_desc; - if (true == midc->in_use) { + if (true == midc->busy) { /*trying to free ch in use!!!!!*/ pr_err("ERR_MDMA: trying to free ch in use\n"); } - + pm_runtime_put(&mid->pdev->dev); spin_lock_bh(&midc->lock); midc->descs_allocated = 0; list_for_each_entry_safe(desc, _desc, &midc->active_list, desc_node) { @@ -639,6 +640,7 @@ static void intel_mid_dma_free_chan_resources(struct dma_chan *chan) } spin_unlock_bh(&midc->lock); midc->in_use = false; + midc->busy = false; /* Disable CH interrupts */ iowrite32(MASK_INTR_REG(midc->ch_id), mid->dma_base + MASK_BLOCK); iowrite32(MASK_INTR_REG(midc->ch_id), mid->dma_base + MASK_ERR); @@ -659,11 +661,20 @@ static int intel_mid_dma_alloc_chan_resources(struct dma_chan *chan) dma_addr_t phys; int i = 0; + pm_runtime_get_sync(&mid->pdev->dev); + + if (mid->state == SUSPENDED) { + if (dma_resume(mid->pdev)) { + pr_err("ERR_MDMA: resume failed"); + return -EFAULT; + } + } /* ASSERT: channel is idle */ if (test_ch_en(mid->dma_base, midc->ch_id)) { /*ch is not idle*/ pr_err("ERR_MDMA: ch not idle\n"); + pm_runtime_put(&mid->pdev->dev); return -EIO; } midc->completed = chan->cookie = 1; @@ -674,6 +685,7 @@ static int intel_mid_dma_alloc_chan_resources(struct dma_chan *chan) desc = pci_pool_alloc(mid->dma_pool, GFP_KERNEL, &phys); if (!desc) { pr_err("ERR_MDMA: desc failed\n"); + pm_runtime_put(&mid->pdev->dev); return -ENOMEM; /*check*/ } @@ -686,7 +698,8 @@ static int intel_mid_dma_alloc_chan_resources(struct dma_chan *chan) list_add_tail(&desc->desc_node, &midc->free_list); } spin_unlock_bh(&midc->lock); - midc->in_use = false; + midc->in_use = true; + midc->busy = false; pr_debug("MID_DMA: Desc alloc done ret: %d desc\n", i); return i; } @@ -884,6 +897,7 @@ static int mid_setup_dma(struct pci_dev *pdev) pr_debug("MDMA:Adding %d channel for this controller\n", dma->max_chan); /*init CH structures*/ dma->intr_mask = 0; + dma->state = RUNNING; for (i = 0; i < dma->max_chan; i++) { struct intel_mid_dma_chan *midch = &dma->ch[i]; @@ -1070,6 +1084,9 @@ static int __devinit intel_mid_dma_probe(struct pci_dev *pdev, if (err) goto err_dma; + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_allow(&pdev->dev); return 0; err_dma: @@ -1104,6 +1121,85 @@ static void __devexit intel_mid_dma_remove(struct pci_dev *pdev) pci_disable_device(pdev); } +/* Power Management */ +/* +* dma_suspend - PCI suspend function +* +* @pci: PCI device structure +* @state: PM message +* +* This function is called by OS when a power event occurs +*/ +int dma_suspend(struct pci_dev *pci, pm_message_t state) +{ + int i; + struct middma_device *device = pci_get_drvdata(pci); + pr_debug("MDMA: dma_suspend called\n"); + + for (i = 0; i < device->max_chan; i++) { + if (device->ch[i].in_use) + return -EAGAIN; + } + device->state = SUSPENDED; + pci_set_drvdata(pci, device); + pci_save_state(pci); + pci_disable_device(pci); + pci_set_power_state(pci, PCI_D3hot); + return 0; +} + +/** +* dma_resume - PCI resume function +* +* @pci: PCI device structure +* +* This function is called by OS when a power event occurs +*/ +int dma_resume(struct pci_dev *pci) +{ + int ret; + struct middma_device *device = pci_get_drvdata(pci); + + pr_debug("MDMA: dma_resume called\n"); + pci_set_power_state(pci, PCI_D0); + pci_restore_state(pci); + ret = pci_enable_device(pci); + if (ret) { + pr_err("MDMA: device cant be enabled for %x\n", pci->device); + return ret; + } + device->state = RUNNING; + iowrite32(REG_BIT0, device->dma_base + DMA_CFG); + pci_set_drvdata(pci, device); + return 0; +} + +static int dma_runtime_suspend(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + return dma_suspend(pci_dev, PMSG_SUSPEND); +} + +static int dma_runtime_resume(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + return dma_resume(pci_dev); +} + +static int dma_runtime_idle(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct middma_device *device = pci_get_drvdata(pdev); + int i; + + for (i = 0; i < device->max_chan; i++) { + if (device->ch[i].in_use) + return -EAGAIN; + } + + return pm_schedule_suspend(dev, 0); +} + /****************************************************************************** * PCI stuff */ @@ -1116,11 +1212,24 @@ static struct pci_device_id intel_mid_dma_ids[] = { }; MODULE_DEVICE_TABLE(pci, intel_mid_dma_ids); +static const struct dev_pm_ops intel_mid_dma_pm = { + .runtime_suspend = dma_runtime_suspend, + .runtime_resume = dma_runtime_resume, + .runtime_idle = dma_runtime_idle, +}; + static struct pci_driver intel_mid_dma_pci = { .name = "Intel MID DMA", .id_table = intel_mid_dma_ids, .probe = intel_mid_dma_probe, .remove = __devexit_p(intel_mid_dma_remove), +#ifdef CONFIG_PM + .suspend = dma_suspend, + .resume = dma_resume, + .driver = { + .pm = &intel_mid_dma_pm, + }, +#endif }; static int __init intel_mid_dma_init(void) diff --git a/drivers/dma/intel_mid_dma_regs.h b/drivers/dma/intel_mid_dma_regs.h index d81aa658ab09..a12dd2572dc3 100644 --- a/drivers/dma/intel_mid_dma_regs.h +++ b/drivers/dma/intel_mid_dma_regs.h @@ -29,7 +29,7 @@ #include #include -#define INTEL_MID_DMA_DRIVER_VERSION "1.0.5" +#define INTEL_MID_DMA_DRIVER_VERSION "1.0.6" #define REG_BIT0 0x00000001 #define REG_BIT8 0x00000100 @@ -152,6 +152,7 @@ union intel_mid_dma_cfg_hi { u32 cfg_hi; }; + /** * struct intel_mid_dma_chan - internal mid representation of a DMA channel * @chan: dma_chan strcture represetation for mid chan @@ -166,6 +167,7 @@ union intel_mid_dma_cfg_hi { * @slave: dma slave struture * @descs_allocated: total number of decsiptors allocated * @dma: dma device struture pointer + * @busy: bool representing if ch is busy (active txn) or not * @in_use: bool representing if ch is in use or not */ struct intel_mid_dma_chan { @@ -181,6 +183,7 @@ struct intel_mid_dma_chan { struct intel_mid_dma_slave *slave; unsigned int descs_allocated; struct middma_device *dma; + bool busy; bool in_use; }; @@ -190,6 +193,10 @@ static inline struct intel_mid_dma_chan *to_intel_mid_dma_chan( return container_of(chan, struct intel_mid_dma_chan, chan); } +enum intel_mid_dma_state { + RUNNING = 0, + SUSPENDED, +}; /** * struct middma_device - internal representation of a DMA device * @pdev: PCI device @@ -205,6 +212,7 @@ static inline struct intel_mid_dma_chan *to_intel_mid_dma_chan( * @max_chan: max number of chs supported (from drv_data) * @block_size: Block size of DMA transfer supported (from drv_data) * @pimr_mask: MMIO register addr for periphral interrupt (from drv_data) + * @state: dma PM device state */ struct middma_device { struct pci_dev *pdev; @@ -220,6 +228,7 @@ struct middma_device { int max_chan; int block_size; unsigned int pimr_mask; + enum intel_mid_dma_state state; }; static inline struct middma_device *to_middma_device(struct dma_device *common) @@ -257,4 +266,7 @@ static inline struct intel_mid_dma_desc *to_intel_mid_dma_desc { return container_of(txd, struct intel_mid_dma_desc, txd); } + +int dma_resume(struct pci_dev *pci); + #endif /*__INTEL_MID_DMAC_REGS_H__*/ -- 2.39.5