net: ethernet: bgmac: init sequence bug

Fix a bug in the 'bgmac' driver init sequence that blind writes for init
sequence where it should preserve most bits other than the ones it is
deliberately manipulating.

The code now checks to see if the adapter needs to be brought out of
reset (where as before it was doing an IDM write to bring it out of
reset regardless of whether it was in reset or not).  Also, removed
unnecessary usleeps (as there is already a read present to flush the
IDM writes).

Signed-off-by: Zac Schroff <zschroff@broadcom.com>
Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Fixes: 0f217913b4a ("net: ethernet: bgmac: Add platform device support")
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bgmac-platform.c b/drivers/net/ethernet/broadcom/bgmac-platform.c
index 7b1af950f312f30b2b6caae941a2a39e47caa3fd..da1b8b225eb9d31e001435ee33c7362f3c5565b5 100644 (file)
--- a/drivers/net/ethernet/broadcom/bgmac-platform.c
+++ b/drivers/net/ethernet/broadcom/bgmac-platform.c
@@ -51,8 +51,7 @@ static void platform_bgmac_idm_write(struct bgmac *bgmac, u16 offset, u32 value)
 
 static bool platform_bgmac_clk_enabled(struct bgmac *bgmac)
 {
-       if ((bgmac_idm_read(bgmac, BCMA_IOCTL) &
-            (BCMA_IOCTL_CLK | BCMA_IOCTL_FGC)) != BCMA_IOCTL_CLK)
+       if ((bgmac_idm_read(bgmac, BCMA_IOCTL) & BGMAC_CLK_EN) != BGMAC_CLK_EN)
                return false;
        if (bgmac_idm_read(bgmac, BCMA_RESET_CTL) & BCMA_RESET_CTL_RESET)
                return false;
@@ -61,15 +60,25 @@ static bool platform_bgmac_clk_enabled(struct bgmac *bgmac)
 
 static void platform_bgmac_clk_enable(struct bgmac *bgmac, u32 flags)
 {
-       bgmac_idm_write(bgmac, BCMA_IOCTL,
-                       (BCMA_IOCTL_CLK | BCMA_IOCTL_FGC | flags));
-       bgmac_idm_read(bgmac, BCMA_IOCTL);
+       u32 val;
 
-       bgmac_idm_write(bgmac, BCMA_RESET_CTL, 0);
-       bgmac_idm_read(bgmac, BCMA_RESET_CTL);
-       udelay(1);
+       /* The Reset Control register only contains a single bit to show if the
+        * controller is currently in reset.  Do a sanity check here, just in
+        * case the bootloader happened to leave the device in reset.
+        */
+       val = bgmac_idm_read(bgmac, BCMA_RESET_CTL);
+       if (val) {
+               bgmac_idm_write(bgmac, BCMA_RESET_CTL, 0);
+               bgmac_idm_read(bgmac, BCMA_RESET_CTL);
+               udelay(1);
+       }
 
-       bgmac_idm_write(bgmac, BCMA_IOCTL, (BCMA_IOCTL_CLK | flags));
+       val = bgmac_idm_read(bgmac, BCMA_IOCTL);
+       /* Some bits of BCMA_IOCTL set by HW/ATF and should not change */
+       val |= flags & ~(BGMAC_AWCACHE | BGMAC_ARCACHE | BGMAC_AWUSER |
+                        BGMAC_ARUSER);
+       val |= BGMAC_CLK_EN;
+       bgmac_idm_write(bgmac, BCMA_IOCTL, val);
        bgmac_idm_read(bgmac, BCMA_IOCTL);
        udelay(1);
 }

diff --git a/drivers/net/ethernet/broadcom/bgmac.h b/drivers/net/ethernet/broadcom/bgmac.h
index 248727dc62f22c2ae2aa6f640f1b2cf91230a133..6d1c6ff1ed963ef6bd672b8cd792b7b529c09b27 100644 (file)
--- a/drivers/net/ethernet/broadcom/bgmac.h
+++ b/drivers/net/ethernet/broadcom/bgmac.h
@@ -213,6 +213,22 @@
 /* BCMA GMAC core specific IO Control (BCMA_IOCTL) flags */
 #define BGMAC_BCMA_IOCTL_SW_CLKEN              0x00000004      /* PHY Clock Enable */
 #define BGMAC_BCMA_IOCTL_SW_RESET              0x00000008      /* PHY Reset */
+/* The IOCTL values appear to be different in NS, NSP, and NS2, and do not match
+ * the values directly above
+ */
+#define BGMAC_CLK_EN                           BIT(0)
+#define BGMAC_RESERVED_0                       BIT(1)
+#define BGMAC_SOURCE_SYNC_MODE_EN              BIT(2)
+#define BGMAC_DEST_SYNC_MODE_EN                        BIT(3)
+#define BGMAC_TX_CLK_OUT_INVERT_EN             BIT(4)
+#define BGMAC_DIRECT_GMII_MODE                 BIT(5)
+#define BGMAC_CLK_250_SEL                      BIT(6)
+#define BGMAC_AWCACHE                          (0xf << 7)
+#define BGMAC_RESERVED_1                       (0x1f << 11)
+#define BGMAC_ARCACHE                          (0xf << 16)
+#define BGMAC_AWUSER                           (0x3f << 20)
+#define BGMAC_ARUSER                           (0x3f << 26)
+#define BGMAC_RESERVED                         BIT(31)
 
 /* BCMA GMAC core specific IO status (BCMA_IOST) flags */
 #define BGMAC_BCMA_IOST_ATTACHED               0x00000800