staging: mt7621-pci: avoid use of global variable 'pcie_link_status'

'pcie_link_status' is a global variable which is being used as a
mask to know which virtual bridges are or not enabled. Instead of
this extract a new 'mt7621_pcie_init_virtual_bridges' function where
a similar local variable is used for the same task. This allow us to
properly configure the virtual PCI-PCI bridges in configuration
registers of the mt7621 pci controller. For a correct initiation of
which is connected use 'enabled' field of 'mt7621_pcie_port' struct.
With this change driver probe function gets a bit cleaner and readable.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/mt7621-pci/pci-mt7621.c b/drivers/staging/mt7621-pci/pci-mt7621.c
index 5f07b53..50c439b 100644 (file)
--- a/drivers/staging/mt7621-pci/pci-mt7621.c
+++ b/drivers/staging/mt7621-pci/pci-mt7621.c
@@ -64,6 +64,14 @@
 #define MT7621_PCIE_OFFSET             0x2000
 #define MT7621_NEXT_PORT               0x1000
 
+#define MT7621_BR0_MASK                        GENMASK(19, 16)
+#define MT7621_BR1_MASK                        GENMASK(23, 20)
+#define MT7621_BR2_MASK                        GENMASK(27, 24)
+#define MT7621_BR_ALL_MASK             GENMASK(27, 16)
+#define MT7621_BR0_SHIFT               16
+#define MT7621_BR1_SHIFT               20
+#define MT7621_BR2_SHIFT               24
+
 #define RALINK_PCI_BAR0SETUP_ADDR      0x0010
 #define RALINK_PCI_IMBASEBAR0_ADDR     0x0018
 #define RALINK_PCI_ID                  0x0030
@@ -82,8 +90,6 @@
 
 #define MEMORY_BASE 0x0
 
-static int pcie_link_status;
-
 /* pcie phy related macros */
 #define RALINK_PCIEPHY_P0P1_CTL_OFFSET 0x9000
 #define RALINK_PCIEPHY_P2_CTL_OFFSET   0xA000
@@ -589,10 +595,8 @@ static int mt7621_pcie_init_port(struct mt7621_pcie_port *port)
                dev_err(dev, "pcie%d no card, disable it (RST & CLK)\n", slot);
                reset_control_assert(port->pcie_rst);
                rt_sysc_m32(BIT(24 + slot), 0, RALINK_CLKCFG1);
-               pcie_link_status &= ~(1 << slot);
                port->enabled = false;
        } else {
-               pcie_link_status |= BIT(slot);
                port->enabled = true;
                val = pcie_read(pcie, RALINK_PCI_PCIMSK_ADDR);
                /* enable pcie interrupt */
@@ -643,6 +647,70 @@ static void mt7621_pcie_enable_ports(struct mt7621_pcie *pcie)
        }
 }
 
+static int mt7621_pcie_init_virtual_bridges(struct mt7621_pcie *pcie)
+{
+       u32 pcie_link_status = 0;
+       u32 val= 0;
+       struct mt7621_pcie_port *port;
+
+       list_for_each_entry(port, &pcie->ports, list) {
+               u32 slot = port->slot;
+
+               if (port->enabled)
+                       pcie_link_status |= BIT(slot);
+       }
+
+       if (pcie_link_status == 0)
+               return -1;
+
+       /*
+        * pcie(2/1/0) link status pcie2_num    pcie1_num       pcie0_num
+        * 3'b000                  x            x               x
+        * 3'b001                  x            x               0
+        * 3'b010                  x            0               x
+        * 3'b011                  x            1               0
+        * 3'b100                  0            x               x
+        * 3'b101                  1            x               0
+        * 3'b110                  1            0               x
+        * 3'b111                  2            1               0
+        */
+       switch (pcie_link_status) {
+       case 2:
+               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
+               val &= ~(MT7621_BR0_MASK | MT7621_BR1_MASK);
+               val |= 0x1 << MT7621_BR0_SHIFT;
+               val |= 0x0 << MT7621_BR1_SHIFT;
+               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
+               break;
+       case 4:
+               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
+               val &= ~MT7621_BR_ALL_MASK;
+               val |= 0x1 << MT7621_BR0_SHIFT;
+               val |= 0x2 << MT7621_BR1_SHIFT;
+               val |= 0x0 << MT7621_BR2_SHIFT;
+               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
+               break;
+       case 5:
+               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
+               val &= ~MT7621_BR_ALL_MASK;
+               val |= 0x0 << MT7621_BR0_SHIFT;
+               val |= 0x2 << MT7621_BR1_SHIFT;
+               val |= 0x1 << MT7621_BR2_SHIFT;
+               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
+               break;
+       case 6:
+               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
+               val &= ~MT7621_BR_ALL_MASK;
+               val |= 0x2 << MT7621_BR0_SHIFT;
+               val |= 0x0 << MT7621_BR1_SHIFT;
+               val |= 0x1 << MT7621_BR2_SHIFT;
+               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
+               break;
+       }
+
+       return 0;
+}
+
 static int mt7621_pcie_request_resources(struct mt7621_pcie *pcie,
                                         struct list_head *res)
 {
@@ -693,7 +761,6 @@ static int mt7621_pci_probe(struct platform_device *pdev)
        struct pci_host_bridge *bridge;
        struct mt7621_pcie_port *port, *tmp;
        int err;
-       u32 val = 0;
        LIST_HEAD(res);
 
        if (!dev->of_node)
@@ -751,52 +818,10 @@ static int mt7621_pci_probe(struct platform_device *pdev)
        *(unsigned int *)(0xbe000620) |= BIT(19) | BIT(8) | BIT(7);             // set DATA
        mdelay(1000);
 
-       if (pcie_link_status == 0)
+       err = mt7621_pcie_init_virtual_bridges(pcie);
+       if (err) {
+               dev_err(dev, "Nothing is connected in virtual bridges. Exiting...");
                return 0;
-
-/*
-pcie(2/1/0) link status        pcie2_num       pcie1_num       pcie0_num
-3'b000                 x               x               x
-3'b001                 x               x               0
-3'b010                 x               0               x
-3'b011                 x               1               0
-3'b100                 0               x               x
-3'b101                 1               x               0
-3'b110                 1               0               x
-3'b111                 2               1               0
-*/
-       switch (pcie_link_status) {
-       case 2:
-               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
-               val &= ~0x00ff0000;
-               val |= 0x1 << 16;       // port 0
-               val |= 0x0 << 20;       // port 1
-               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
-               break;
-       case 4:
-               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
-               val &= ~0x0fff0000;
-               val |= 0x1 << 16;       //port0
-               val |= 0x2 << 20;       //port1
-               val |= 0x0 << 24;       //port2
-               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
-               break;
-       case 5:
-               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
-               val &= ~0x0fff0000;
-               val |= 0x0 << 16;       //port0
-               val |= 0x2 << 20;       //port1
-               val |= 0x1 << 24;       //port2
-               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
-               break;
-       case 6:
-               val = pcie_read(pcie, RALINK_PCI_PCICFG_ADDR);
-               val &= ~0x0fff0000;
-               val |= 0x2 << 16;       //port0
-               val |= 0x0 << 20;       //port1
-               val |= 0x1 << 24;       //port2
-               pcie_write(pcie, val, RALINK_PCI_PCICFG_ADDR);
-               break;
        }
 
        pcie_write(pcie, 0xffffffff, RALINK_PCI_MEMBASE);