powerpc/85xx: Add SWIOTLB support to FSL boards

Add the platform-specific code for enabling SWIOTLB if needed on P2020DS,
MPC85xx DS, and MPC85xx MDS boards as they are capable of having >4G of
memory.

We determine if we need to enable swiotlb based on how much memory is in
the board and if it exceeds 4G or what we can map via PCI inbound
windows.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

4 files changed, 59 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/85xx/Kconfig b/arch/powerpc/platforms/85xx/Kconfig
index 43d385cedcd7..0ee5b12c7d95 100644
--- a/arch/powerpc/platforms/85xx/Kconfig
+++ b/arch/powerpc/platforms/85xx/Kconfig
@@ -35,12 +35,14 @@ config MPC85xx_MDS
         select DEFAULT_UIMAGE
         select PHYLIB
         select HAS_RAPIDIO
+        select SWIOTLB
         help
           This option enables support for the MPC85xx MDS board
 
 config MPC8536_DS
         bool "Freescale MPC8536 DS"
         select DEFAULT_UIMAGE
+        select SWIOTLB
         help
           This option enables support for the MPC8536 DS board
 
@@ -49,6 +51,7 @@ config MPC85xx_DS
         select PPC_I8259
         select DEFAULT_UIMAGE
         select FSL_ULI1575
+        select SWIOTLB
         help
           This option enables support for the MPC85xx DS (MPC8544 DS) board
 
diff --git a/arch/powerpc/platforms/85xx/mpc8536_ds.c b/arch/powerpc/platforms/85xx/mpc8536_ds.c
index 63efca20d7bd..055ff417bae9 100644
--- a/arch/powerpc/platforms/85xx/mpc8536_ds.c
+++ b/arch/powerpc/platforms/85xx/mpc8536_ds.c
@@ -17,6 +17,7 @@
 #include <linux/seq_file.h>
 #include <linux/interrupt.h>
 #include <linux/of_platform.h>
+#include <linux/lmb.h>
 
 #include <asm/system.h>
 #include <asm/time.h>
@@ -26,6 +27,7 @@
 #include <asm/prom.h>
 #include <asm/udbg.h>
 #include <asm/mpic.h>
+#include <asm/swiotlb.h>
 
 #include <sysdev/fsl_soc.h>
 #include <sysdev/fsl_pci.h>
@@ -65,7 +67,9 @@ static void __init mpc8536_ds_setup_arch(void)
 {
 #ifdef CONFIG_PCI
         struct device_node *np;
+        struct pci_controller *hose;
 #endif
+        dma_addr_t max = 0xffffffff;
 
         if (ppc_md.progress)
                 ppc_md.progress("mpc8536_ds_setup_arch()", 0);
@@ -80,11 +84,22 @@ static void __init mpc8536_ds_setup_arch(void)
                                 fsl_add_bridge(np, 1);
                         else
                                 fsl_add_bridge(np, 0);
+
+                        hose = pci_find_hose_for_OF_device(np);
+                        max = min(max, hose->dma_window_base_cur +
+                                        hose->dma_window_size);
                 }
         }
 
 #endif
 
+#ifdef CONFIG_SWIOTLB
+        if (lmb_end_of_DRAM() > max) {
+                ppc_swiotlb_enable = 1;
+                set_pci_dma_ops(&swiotlb_pci_dma_ops);
+        }
+#endif
+
         printk("MPC8536 DS board from Freescale Semiconductor\n");
 }
 
@@ -102,6 +117,8 @@ static int __init mpc8536_ds_publish_devices(void)
 }
 machine_device_initcall(mpc8536_ds, mpc8536_ds_publish_devices);
 
+machine_arch_initcall(mpc8536_ds, swiotlb_setup_bus_notifier);
+
 /*
  * Called very early, device-tree isn't unflattened
  */
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_ds.c b/arch/powerpc/platforms/85xx/mpc85xx_ds.c
index 53d5851a6c97..849c0ac0025f 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_ds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_ds.c
@@ -20,6 +20,7 @@
 #include <linux/seq_file.h>
 #include <linux/interrupt.h>
 #include <linux/of_platform.h>
+#include <linux/lmb.h>
 
 #include <asm/system.h>
 #include <asm/time.h>
@@ -30,6 +31,7 @@
 #include <asm/udbg.h>
 #include <asm/mpic.h>
 #include <asm/i8259.h>
+#include <asm/swiotlb.h>
 
 #include <sysdev/fsl_soc.h>
 #include <sysdev/fsl_pci.h>
@@ -155,7 +157,9 @@ static void __init mpc85xx_ds_setup_arch(void)
 {
 #ifdef CONFIG_PCI
         struct device_node *np;
+        struct pci_controller *hose;
 #endif
+        dma_addr_t max = 0xffffffff;
 
         if (ppc_md.progress)
                 ppc_md.progress("mpc85xx_ds_setup_arch()", 0);
@@ -171,6 +175,10 @@ static void __init mpc85xx_ds_setup_arch(void)
                                 fsl_add_bridge(np, 1);
                         else
                                 fsl_add_bridge(np, 0);
+
+                        hose = pci_find_hose_for_OF_device(np);
+                        max = min(max, hose->dma_window_base_cur +
+                                        hose->dma_window_size);
                 }
         }
 
@@ -181,6 +189,13 @@ static void __init mpc85xx_ds_setup_arch(void)
         mpc85xx_smp_init();
 #endif
 
+#ifdef CONFIG_SWIOTLB
+        if (lmb_end_of_DRAM() > max) {
+                ppc_swiotlb_enable = 1;
+                set_pci_dma_ops(&swiotlb_pci_dma_ops);
+        }
+#endif
+
         printk("MPC85xx DS board from Freescale Semiconductor\n");
 }
 
@@ -217,6 +232,10 @@ machine_device_initcall(mpc8544_ds, mpc85xxds_publish_devices);
 machine_device_initcall(mpc8572_ds, mpc85xxds_publish_devices);
 machine_device_initcall(p2020_ds, mpc85xxds_publish_devices);
 
+machine_arch_initcall(mpc8544_ds, swiotlb_setup_bus_notifier);
+machine_arch_initcall(mpc8572_ds, swiotlb_setup_bus_notifier);
+machine_arch_initcall(p2020_ds, swiotlb_setup_bus_notifier);
+
 /*
  * Called very early, device-tree isn't unflattened
  */
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_mds.c b/arch/powerpc/platforms/85xx/mpc85xx_mds.c
index b2c0a4319973..77f90b356356 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_mds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_mds.c
@@ -33,6 +33,7 @@
 #include <linux/of_platform.h>
 #include <linux/of_device.h>
 #include <linux/phy.h>
+#include <linux/lmb.h>
 
 #include <asm/system.h>
 #include <asm/atomic.h>
@@ -49,6 +50,7 @@
 #include <asm/qe.h>
 #include <asm/qe_ic.h>
 #include <asm/mpic.h>
+#include <asm/swiotlb.h>
 
 #undef DEBUG
 #ifdef DEBUG
@@ -155,6 +157,10 @@ static void __init mpc85xx_mds_setup_arch(void)
 {
         struct device_node *np;
         static u8 __iomem *bcsr_regs = NULL;
+#ifdef CONFIG_PCI
+        struct pci_controller *hose;
+#endif
+        dma_addr_t max = 0xffffffff;
 
         if (ppc_md.progress)
                 ppc_md.progress("mpc85xx_mds_setup_arch()", 0);
@@ -179,6 +185,10 @@ static void __init mpc85xx_mds_setup_arch(void)
                                 fsl_add_bridge(np, 1);
                         else
                                 fsl_add_bridge(np, 0);
+
+                        hose = pci_find_hose_for_OF_device(np);
+                        max = min(max, hose->dma_window_base_cur +
+                                        hose->dma_window_size);
                 }
         }
 #endif
@@ -227,6 +237,13 @@ static void __init mpc85xx_mds_setup_arch(void)
                 iounmap(bcsr_regs);
         }
 #endif  /* CONFIG_QUICC_ENGINE */
+
+#ifdef CONFIG_SWIOTLB
+        if (lmb_end_of_DRAM() > max) {
+                ppc_swiotlb_enable = 1;
+                set_pci_dma_ops(&swiotlb_pci_dma_ops);
+        }
+#endif
 }
 
 
@@ -281,6 +298,9 @@ static int __init mpc85xx_publish_devices(void)
 machine_device_initcall(mpc8568_mds, mpc85xx_publish_devices);
 machine_device_initcall(mpc8569_mds, mpc85xx_publish_devices);
 
+machine_arch_initcall(mpc8568_mds, swiotlb_setup_bus_notifier);
+machine_arch_initcall(mpc8569_mds, swiotlb_setup_bus_notifier);
+
 static void __init mpc85xx_mds_pic_init(void)
 {
         struct mpic *mpic;