From e3075fd6f80c9a6ce678fa2f5bbdb2824c506c6c Mon Sep 17 00:00:00 2001 From: Kuppuswamy Sathyanarayanan Date: Sat, 7 Oct 2017 15:19:51 -0700 Subject: [PATCH] platform/x86: intel_pmc_ipc: Use spin_lock to protect GCR updates Currently, update_no_reboot_bit() function implemented in this driver uses mutex_lock() to protect its register updates. But this function is called with in atomic context in iTCO_wdt_start() and iTCO_wdt_stop() functions in iTCO_wdt.c driver, which in turn causes "sleeping into atomic context" issue. This patch fixes this issue by replacing the mutex_lock() with spin_lock() to protect the GCR read/write/update APIs. Fixes: 9d855d4 ("platform/x86: intel_pmc_ipc: Fix iTCO_wdt GCS memory mapping failure") Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Andy Shevchenko --- drivers/platform/x86/intel_pmc_ipc.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/drivers/platform/x86/intel_pmc_ipc.c b/drivers/platform/x86/intel_pmc_ipc.c index 751b1212d01c..e03fa31446ca 100644 --- a/drivers/platform/x86/intel_pmc_ipc.c +++ b/drivers/platform/x86/intel_pmc_ipc.c @@ -33,6 +33,7 @@ #include #include #include +#include #include @@ -131,6 +132,7 @@ static struct intel_pmc_ipc_dev { /* gcr */ void __iomem *gcr_mem_base; bool has_gcr_regs; + spinlock_t gcr_lock; /* punit */ struct platform_device *punit_dev; @@ -225,17 +227,17 @@ int intel_pmc_gcr_read(u32 offset, u32 *data) { int ret; - mutex_lock(&ipclock); + spin_lock(&ipcdev.gcr_lock); ret = is_gcr_valid(offset); if (ret < 0) { - mutex_unlock(&ipclock); + spin_unlock(&ipcdev.gcr_lock); return ret; } *data = readl(ipcdev.gcr_mem_base + offset); - mutex_unlock(&ipclock); + spin_unlock(&ipcdev.gcr_lock); return 0; } @@ -255,17 +257,17 @@ int intel_pmc_gcr_write(u32 offset, u32 data) { int ret; - mutex_lock(&ipclock); + spin_lock(&ipcdev.gcr_lock); ret = is_gcr_valid(offset); if (ret < 0) { - mutex_unlock(&ipclock); + spin_unlock(&ipcdev.gcr_lock); return ret; } writel(data, ipcdev.gcr_mem_base + offset); - mutex_unlock(&ipclock); + spin_unlock(&ipcdev.gcr_lock); return 0; } @@ -287,7 +289,7 @@ int intel_pmc_gcr_update(u32 offset, u32 mask, u32 val) u32 new_val; int ret = 0; - mutex_lock(&ipclock); + spin_lock(&ipcdev.gcr_lock); ret = is_gcr_valid(offset); if (ret < 0) @@ -309,7 +311,7 @@ int intel_pmc_gcr_update(u32 offset, u32 mask, u32 val) } gcr_ipc_unlock: - mutex_unlock(&ipclock); + spin_unlock(&ipcdev.gcr_lock); return ret; } EXPORT_SYMBOL_GPL(intel_pmc_gcr_update); @@ -489,6 +491,8 @@ static int ipc_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) pmc->irq_mode = IPC_TRIGGER_MODE_IRQ; + spin_lock_init(&ipcdev.gcr_lock); + ret = pcim_enable_device(pdev); if (ret) return ret; @@ -903,6 +907,7 @@ static int ipc_plat_probe(struct platform_device *pdev) ipcdev.dev = &pdev->dev; ipcdev.irq_mode = IPC_TRIGGER_MODE_IRQ; init_completion(&ipcdev.cmd_complete); + spin_lock_init(&ipcdev.gcr_lock); ipcdev.irq = platform_get_irq(pdev, 0); if (ipcdev.irq < 0) {