tg3: Add APE scratchpad read function

for retreiving temperature sensor data.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 86 insertions, 2 deletions

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 5dda3ced90e1..26ca36810e72 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -752,6 +752,85 @@ static int tg3_ape_event_lock(struct tg3 *tp, u32 timeout_us)
         return timeout_us ? 0 : -EBUSY;
 }
 
+static int tg3_ape_wait_for_event(struct tg3 *tp, u32 timeout_us)
+{
+        u32 i, apedata;
+
+        for (i = 0; i < timeout_us / 10; i++) {
+                apedata = tg3_ape_read32(tp, TG3_APE_EVENT_STATUS);
+
+                if (!(apedata & APE_EVENT_STATUS_EVENT_PENDING))
+                        break;
+
+                udelay(10);
+        }
+
+        return i == timeout_us / 10;
+}
+
+int tg3_ape_scratchpad_read(struct tg3 *tp, u32 *data, u32 base_off, u32 len)
+{
+        int err;
+        u32 i, bufoff, msgoff, maxlen, apedata;
+
+        if (!tg3_flag(tp, APE_HAS_NCSI))
+                return 0;
+
+        apedata = tg3_ape_read32(tp, TG3_APE_SEG_SIG);
+        if (apedata != APE_SEG_SIG_MAGIC)
+                return -ENODEV;
+
+        apedata = tg3_ape_read32(tp, TG3_APE_FW_STATUS);
+        if (!(apedata & APE_FW_STATUS_READY))
+                return -EAGAIN;
+
+        bufoff = tg3_ape_read32(tp, TG3_APE_SEG_MSG_BUF_OFF) +
+                 TG3_APE_SHMEM_BASE;
+        msgoff = bufoff + 2 * sizeof(u32);
+        maxlen = tg3_ape_read32(tp, TG3_APE_SEG_MSG_BUF_LEN);
+
+        while (len) {
+                u32 length;
+
+                /* Cap xfer sizes to scratchpad limits. */
+                length = (len > maxlen) ? maxlen : len;
+                len -= length;
+
+                apedata = tg3_ape_read32(tp, TG3_APE_FW_STATUS);
+                if (!(apedata & APE_FW_STATUS_READY))
+                        return -EAGAIN;
+
+                /* Wait for up to 1 msec for APE to service previous event. */
+                err = tg3_ape_event_lock(tp, 1000);
+                if (err)
+                        return err;
+
+                apedata = APE_EVENT_STATUS_DRIVER_EVNT |
+                          APE_EVENT_STATUS_SCRTCHPD_READ |
+                          APE_EVENT_STATUS_EVENT_PENDING;
+                tg3_ape_write32(tp, TG3_APE_EVENT_STATUS, apedata);
+
+                tg3_ape_write32(tp, bufoff, base_off);
+                tg3_ape_write32(tp, bufoff + sizeof(u32), length);
+
+                tg3_ape_unlock(tp, TG3_APE_LOCK_MEM);
+                tg3_ape_write32(tp, TG3_APE_EVENT, APE_EVENT_1);
+
+                base_off += length;
+
+                if (tg3_ape_wait_for_event(tp, 30000))
+                        return -EAGAIN;
+
+                for (i = 0; length; i += 4, length -= 4) {
+                        u32 val = tg3_ape_read32(tp, msgoff + i);
+                        memcpy(data, &val, sizeof(u32));
+                        data++;
+                }
+        }
+
+        return 0;
+}
+
 static int tg3_ape_send_event(struct tg3 *tp, u32 event)
 {
         int err;
diff --git a/drivers/net/ethernet/broadcom/tg3.h b/drivers/net/ethernet/broadcom/tg3.h
index 93865f899a4f..f8a0d9c0e990 100644
--- a/drivers/net/ethernet/broadcom/tg3.h
+++ b/drivers/net/ethernet/broadcom/tg3.h
@@ -2311,10 +2311,11 @@
 #define  APE_LOCK_REQ_DRIVER             0x00001000
 #define TG3_APE_LOCK_GRANT              0x004c
 #define  APE_LOCK_GRANT_DRIVER           0x00001000
-#define TG3_APE_SEG_SIG                 0x4000
-#define  APE_SEG_SIG_MAGIC               0x41504521
 
 /* APE shared memory.  Accessible through BAR1 */
+#define TG3_APE_SHMEM_BASE              0x4000
+#define TG3_APE_SEG_SIG                 0x4000
+#define  APE_SEG_SIG_MAGIC               0x41504521
 #define TG3_APE_FW_STATUS               0x400c
 #define  APE_FW_STATUS_READY             0x00000100
 #define TG3_APE_FW_FEATURES             0x4010
@@ -2327,6 +2328,8 @@
 #define  APE_FW_VERSION_REVMSK           0x0000ff00
 #define  APE_FW_VERSION_REVSFT           8
 #define  APE_FW_VERSION_BLDMSK           0x000000ff
+#define TG3_APE_SEG_MSG_BUF_OFF         0x401c
+#define TG3_APE_SEG_MSG_BUF_LEN         0x4020
 #define TG3_APE_HOST_SEG_SIG            0x4200
 #define  APE_HOST_SEG_SIG_MAGIC          0x484f5354
 #define TG3_APE_HOST_SEG_LEN            0x4204
@@ -2353,6 +2356,8 @@
 
 #define  APE_EVENT_STATUS_DRIVER_EVNT    0x00000010
 #define  APE_EVENT_STATUS_STATE_CHNGE    0x00000500
+#define  APE_EVENT_STATUS_SCRTCHPD_READ  0x00001600
+#define  APE_EVENT_STATUS_SCRTCHPD_WRITE 0x00001700
 #define  APE_EVENT_STATUS_STATE_START    0x00010000
 #define  APE_EVENT_STATUS_STATE_UNLOAD   0x00020000
 #define  APE_EVENT_STATUS_STATE_WOL      0x00030000