[SCSI] mpt fusion: Request I/O resources only when required

This patch modifies the I/O resource allocation behavior of FUSION
driver.  The current version of driver allocates the I/O resources
even if they are not required and this creates trouble in low resource
environments.  This driver now uses
pci_enable_device_mem/pci_enable_device functions to differentiate the
resource allocations.

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

2 files changed, 44 insertions, 7 deletions

diff --git a/drivers/message/fusion/mptbase.c b/drivers/message/fusion/mptbase.c
index d381c38ccbaf..bfda731696f7 100644
--- a/drivers/message/fusion/mptbase.c
+++ b/drivers/message/fusion/mptbase.c
@@ -1470,9 +1470,6 @@ mpt_attach(struct pci_dev *pdev, const struct pci_device_id *id)
         if (mpt_debug_level)
                 printk(KERN_INFO MYNAM ": mpt_debug_level=%xh\n", mpt_debug_level);
 
-        if (pci_enable_device(pdev))
-                return r;
-
         ioc = kzalloc(sizeof(MPT_ADAPTER), GFP_ATOMIC);
         if (ioc == NULL) {
                 printk(KERN_ERR MYNAM ": ERROR - Insufficient memory to add adapter!\n");
@@ -1482,6 +1479,20 @@ mpt_attach(struct pci_dev *pdev, const struct pci_device_id *id)
         ioc->id = mpt_ids++;
         sprintf(ioc->name, "ioc%d", ioc->id);
 
+        ioc->bars = pci_select_bars(pdev, IORESOURCE_MEM);
+        if (pci_enable_device_mem(pdev)) {
+                kfree(ioc);
+                printk(MYIOC_s_ERR_FMT "pci_enable_device_mem() "
+                       "failed\n", ioc->name);
+                return r;
+        }
+        if (pci_request_selected_regions(pdev, ioc->bars, "mpt")) {
+                kfree(ioc);
+                printk(MYIOC_s_ERR_FMT "pci_request_selected_regions() with "
+                       "MEM failed\n", ioc->name);
+                return r;
+        }
+
         dinitprintk(ioc, printk(MYIOC_s_INFO_FMT ": mpt_adapter_install\n", ioc->name));
 
         if (!pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
@@ -1794,6 +1805,7 @@ mpt_suspend(struct pci_dev *pdev, pm_message_t state)
         CHIPREG_WRITE32(&ioc->chip->IntStatus, 0);
 
         pci_disable_device(pdev);
+        pci_release_selected_regions(pdev, ioc->bars);
         pci_set_power_state(pdev, device_state);
 
         return 0;
@@ -1810,7 +1822,6 @@ mpt_resume(struct pci_dev *pdev)
         MPT_ADAPTER *ioc = pci_get_drvdata(pdev);
         u32 device_state = pdev->current_state;
         int recovery_state;
-        int err;
 
         printk(MYIOC_s_INFO_FMT
         "pci-resume: pdev=0x%p, slot=%s, Previous operating state [D%d]\n",
@@ -1818,9 +1829,18 @@ mpt_resume(struct pci_dev *pdev)
 
         pci_set_power_state(pdev, 0);
         pci_restore_state(pdev);
-        err = pci_enable_device(pdev);
-        if (err)
-                return err;
+        if (ioc->facts.Flags & MPI_IOCFACTS_FLAGS_FW_DOWNLOAD_BOOT) {
+                ioc->bars = pci_select_bars(ioc->pcidev, IORESOURCE_MEM |
+                        IORESOURCE_IO);
+                if (pci_enable_device(pdev))
+                        return 0;
+        } else {
+                ioc->bars = pci_select_bars(pdev, IORESOURCE_MEM);
+                if (pci_enable_device_mem(pdev))
+                        return 0;
+        }
+        if (pci_request_selected_regions(pdev, ioc->bars, "mpt"))
+                return 0;
 
         /* enable interrupts */
         CHIPREG_WRITE32(&ioc->chip->IntMask, MPI_HIM_DIM);
@@ -1881,6 +1901,7 @@ mpt_signal_reset(u8 index, MPT_ADAPTER *ioc, int reset_phase)
  *              -2 if READY but IOCFacts Failed
  *              -3 if READY but PrimeIOCFifos Failed
  *              -4 if READY but IOCInit Failed
+ *              -5 if failed to enable_device and/or request_selected_regions
  */
 static int
 mpt_do_ioc_recovery(MPT_ADAPTER *ioc, u32 reason, int sleepFlag)
@@ -1979,6 +2000,18 @@ mpt_do_ioc_recovery(MPT_ADAPTER *ioc, u32 reason, int sleepFlag)
                 }
         }
 
+        if ((ret == 0) && (reason == MPT_HOSTEVENT_IOC_BRINGUP) &&
+            (ioc->facts.Flags & MPI_IOCFACTS_FLAGS_FW_DOWNLOAD_BOOT)) {
+                pci_release_selected_regions(ioc->pcidev, ioc->bars);
+                ioc->bars = pci_select_bars(ioc->pcidev, IORESOURCE_MEM |
+                    IORESOURCE_IO);
+                if (pci_enable_device(ioc->pcidev))
+                        return -5;
+                if (pci_request_selected_regions(ioc->pcidev, ioc->bars,
+                        "mpt"))
+                        return -5;
+        }
+
         /*
          * Device is reset now. It must have de-asserted the interrupt line
          * (if it was asserted) and it should be safe to register for the
@@ -2383,6 +2416,9 @@ mpt_adapter_dispose(MPT_ADAPTER *ioc)
                 ioc->memmap = NULL;
         }
 
+        pci_disable_device(ioc->pcidev);
+        pci_release_selected_regions(ioc->pcidev, ioc->bars);
+
 #if defined(CONFIG_MTRR) && 0
         if (ioc->mtrr_reg > 0) {
                 mtrr_del(ioc->mtrr_reg, 0, 0);
diff --git a/drivers/message/fusion/mptbase.h b/drivers/message/fusion/mptbase.h
index b49b706c0020..d83ea96fe135 100644
--- a/drivers/message/fusion/mptbase.h
+++ b/drivers/message/fusion/mptbase.h
@@ -629,6 +629,7 @@ typedef struct _MPT_ADAPTER
         dma_addr_t              HostPageBuffer_dma;
         int                      mtrr_reg;
         struct pci_dev          *pcidev;        /* struct pci_dev pointer */
+        int                     bars;           /* bitmask of BAR's that must be configured */
         u8                      __iomem *memmap;        /* mmap address */
         struct Scsi_Host        *sh;            /* Scsi Host pointer */
         SpiCfgData              spi_data;       /* Scsi config. data */