GART looses it's state only in case of a deepest suspend level. Let's not waste memory if machine doesn't support that suspend level.
Signed-off-by: Dmitry Osipenko <[email protected]> --- drivers/iommu/tegra-gart.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c index 37e708fdbb5a..1557a6a9a438 100644 --- a/drivers/iommu/tegra-gart.c +++ b/drivers/iommu/tegra-gart.c @@ -31,6 +31,8 @@ #include <linux/iommu.h> #include <linux/of.h> +#include <soc/tegra/pmc.h> + #include <asm/cacheflush.h> /* bitmap of the page sizes currently supported */ @@ -354,10 +356,13 @@ static int tegra_gart_suspend(struct device *dev) u32 *data = gart->savedata; unsigned long flags; - spin_lock_irqsave(&gart->pte_lock, flags); - for_each_gart_pte(gart, iova) - *(data++) = gart_read_pte(gart, iova); - spin_unlock_irqrestore(&gart->pte_lock, flags); + if (gart->savedata != NULL) { + spin_lock_irqsave(&gart->pte_lock, flags); + for_each_gart_pte(gart, iova) + *(data++) = gart_read_pte(gart, iova); + spin_unlock_irqrestore(&gart->pte_lock, flags); + } + return 0; } @@ -366,9 +371,12 @@ static int tegra_gart_resume(struct device *dev) struct gart_device *gart = dev_get_drvdata(dev); unsigned long flags; - spin_lock_irqsave(&gart->pte_lock, flags); - do_gart_setup(gart, gart->savedata); - spin_unlock_irqrestore(&gart->pte_lock, flags); + if (gart->savedata != NULL) { + spin_lock_irqsave(&gart->pte_lock, flags); + do_gart_setup(gart, gart->savedata); + spin_unlock_irqrestore(&gart->pte_lock, flags); + } + return 0; } @@ -412,10 +420,16 @@ static int tegra_gart_probe(struct platform_device *pdev) gart->iovmm_base = (dma_addr_t)res_remap->start; gart->page_count = (resource_size(res_remap) >> GART_PAGE_SHIFT); - gart->savedata = vmalloc(sizeof(u32) * gart->page_count); - if (!gart->savedata) { - dev_err(dev, "failed to allocate context save area\n"); - return -ENOMEM; + /* + * The registers store/restore is required only in case of a + * deepest sleep state, do not waste memory if it's unnecessary. + */ + if (tegra_pmc_get_suspend_mode() == TEGRA_SUSPEND_LP0) { + gart->savedata = vmalloc(sizeof(u32) * gart->page_count); + if (!gart->savedata) { + dev_err(dev, "failed to allocate context save area\n"); + return -ENOMEM; + } } platform_set_drvdata(pdev, gart); -- 2.13.2 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
