| Message ID | 20210716082755.428187-6-leobras.c@gmail.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | DDW + Indirect Mapping | expand |
| Related | show |
On 16/07/2021 10:27, Leonardo Bras wrote: > enable_ddw() currently returns the address of the DMA window, which is > considered invalid if has the value 0x00. > > Also, it only considers valid an address returned from find_existing_ddw > if it's not 0x00. > > Changing this behavior makes sense, given the users of enable_ddw() only > need to know if direct mapping is possible. It can also allow a DMA window > starting at 0x00 to be used. > > This will be helpful for using a DDW with indirect mapping, as the window > address will be different than 0x00, but it will not map the whole > partition. > > Signed-off-by: Leonardo Bras <leobras.c@gmail.com> > Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- Looks good to me Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com> > arch/powerpc/platforms/pseries/iommu.c | 36 +++++++++++++------------- > 1 file changed, 18 insertions(+), 18 deletions(-) > > diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c > index 712d1667144a..b34b473bbdc1 100644 > --- a/arch/powerpc/platforms/pseries/iommu.c > +++ b/arch/powerpc/platforms/pseries/iommu.c > @@ -853,25 +853,26 @@ static void remove_ddw(struct device_node *np, bool remove_prop) > np, ret); > } > > -static u64 find_existing_ddw(struct device_node *pdn, int *window_shift) > +static bool find_existing_ddw(struct device_node *pdn, u64 *dma_addr, int *window_shift) > { > struct direct_window *window; > const struct dynamic_dma_window_prop *direct64; > - u64 dma_addr = 0; > + bool found = false; > > spin_lock(&direct_window_list_lock); > /* check if we already created a window and dupe that config if so */ > list_for_each_entry(window, &direct_window_list, list) { > if (window->device == pdn) { > direct64 = window->prop; > - dma_addr = be64_to_cpu(direct64->dma_base); > + *dma_addr = be64_to_cpu(direct64->dma_base); > *window_shift = be32_to_cpu(direct64->window_shift); > + found = true; > break; > } > } > spin_unlock(&direct_window_list_lock); > > - return dma_addr; > + return found; > } > > static struct direct_window *ddw_list_new_entry(struct device_node *pdn, > @@ -1161,20 +1162,20 @@ static int iommu_get_page_shift(u32 query_page_size) > * pdn: the parent pe node with the ibm,dma_window property > * Future: also check if we can remap the base window for our base page size > * > - * returns the dma offset for use by the direct mapped DMA code. > + * returns true if can map all pages (direct mapping), false otherwise.. > */ > -static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) > +static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) > { > int len = 0, ret; > int max_ram_len = order_base_2(ddw_memory_hotplug_max()); > struct ddw_query_response query; > struct ddw_create_response create; > int page_shift; > - u64 dma_addr; > struct device_node *dn; > u32 ddw_avail[DDW_APPLICABLE_SIZE]; > struct direct_window *window; > struct property *win64; > + bool ddw_enabled = false; > struct dynamic_dma_window_prop *ddwprop; > struct failed_ddw_pdn *fpdn; > bool default_win_removed = false; > @@ -1186,9 +1187,10 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) > > mutex_lock(&direct_window_init_mutex); > > - dma_addr = find_existing_ddw(pdn, &len); > - if (dma_addr != 0) > + if (find_existing_ddw(pdn, &dev->dev.archdata.dma_offset, &len)) { > + ddw_enabled = true; > goto out_unlock; > + } > > /* > * If we already went through this for a previous function of > @@ -1342,7 +1344,8 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) > list_add(&window->list, &direct_window_list); > spin_unlock(&direct_window_list_lock); > > - dma_addr = be64_to_cpu(ddwprop->dma_base); > + dev->dev.archdata.dma_offset = be64_to_cpu(ddwprop->dma_base); > + ddw_enabled = true; > goto out_unlock; > > out_free_window: > @@ -1374,10 +1377,10 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) > * as RAM, then we failed to create a window to cover persistent > * memory and need to set the DMA limit. > */ > - if (pmem_present && dma_addr && (len == max_ram_len)) > - dev->dev.bus_dma_limit = dma_addr + (1ULL << len); > + if (pmem_present && ddw_enabled && (len == max_ram_len)) > + dev->dev.bus_dma_limit = dev->dev.archdata.dma_offset + (1ULL << len); > > - return dma_addr; > + return ddw_enabled; > } > > static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev) > @@ -1456,11 +1459,8 @@ static bool iommu_bypass_supported_pSeriesLP(struct pci_dev *pdev, u64 dma_mask) > break; > } > > - if (pdn && PCI_DN(pdn)) { > - pdev->dev.archdata.dma_offset = enable_ddw(pdev, pdn); > - if (pdev->dev.archdata.dma_offset) > - return true; > - } > + if (pdn && PCI_DN(pdn)) > + return enable_ddw(pdev, pdn); > > return false; > } >
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 712d1667144a..b34b473bbdc1 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -853,25 +853,26 @@ static void remove_ddw(struct device_node *np, bool remove_prop) np, ret); } -static u64 find_existing_ddw(struct device_node *pdn, int *window_shift) +static bool find_existing_ddw(struct device_node *pdn, u64 *dma_addr, int *window_shift) { struct direct_window *window; const struct dynamic_dma_window_prop *direct64; - u64 dma_addr = 0; + bool found = false; spin_lock(&direct_window_list_lock); /* check if we already created a window and dupe that config if so */ list_for_each_entry(window, &direct_window_list, list) { if (window->device == pdn) { direct64 = window->prop; - dma_addr = be64_to_cpu(direct64->dma_base); + *dma_addr = be64_to_cpu(direct64->dma_base); *window_shift = be32_to_cpu(direct64->window_shift); + found = true; break; } } spin_unlock(&direct_window_list_lock); - return dma_addr; + return found; } static struct direct_window *ddw_list_new_entry(struct device_node *pdn, @@ -1161,20 +1162,20 @@ static int iommu_get_page_shift(u32 query_page_size) * pdn: the parent pe node with the ibm,dma_window property * Future: also check if we can remap the base window for our base page size * - * returns the dma offset for use by the direct mapped DMA code. + * returns true if can map all pages (direct mapping), false otherwise.. */ -static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) +static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) { int len = 0, ret; int max_ram_len = order_base_2(ddw_memory_hotplug_max()); struct ddw_query_response query; struct ddw_create_response create; int page_shift; - u64 dma_addr; struct device_node *dn; u32 ddw_avail[DDW_APPLICABLE_SIZE]; struct direct_window *window; struct property *win64; + bool ddw_enabled = false; struct dynamic_dma_window_prop *ddwprop; struct failed_ddw_pdn *fpdn; bool default_win_removed = false; @@ -1186,9 +1187,10 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) mutex_lock(&direct_window_init_mutex); - dma_addr = find_existing_ddw(pdn, &len); - if (dma_addr != 0) + if (find_existing_ddw(pdn, &dev->dev.archdata.dma_offset, &len)) { + ddw_enabled = true; goto out_unlock; + } /* * If we already went through this for a previous function of @@ -1342,7 +1344,8 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) list_add(&window->list, &direct_window_list); spin_unlock(&direct_window_list_lock); - dma_addr = be64_to_cpu(ddwprop->dma_base); + dev->dev.archdata.dma_offset = be64_to_cpu(ddwprop->dma_base); + ddw_enabled = true; goto out_unlock; out_free_window: @@ -1374,10 +1377,10 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) * as RAM, then we failed to create a window to cover persistent * memory and need to set the DMA limit. */ - if (pmem_present && dma_addr && (len == max_ram_len)) - dev->dev.bus_dma_limit = dma_addr + (1ULL << len); + if (pmem_present && ddw_enabled && (len == max_ram_len)) + dev->dev.bus_dma_limit = dev->dev.archdata.dma_offset + (1ULL << len); - return dma_addr; + return ddw_enabled; } static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev) @@ -1456,11 +1459,8 @@ static bool iommu_bypass_supported_pSeriesLP(struct pci_dev *pdev, u64 dma_mask) break; } - if (pdn && PCI_DN(pdn)) { - pdev->dev.archdata.dma_offset = enable_ddw(pdev, pdn); - if (pdev->dev.archdata.dma_offset) - return true; - } + if (pdn && PCI_DN(pdn)) + return enable_ddw(pdev, pdn); return false; }