qed: Wait for MCP halt and resume commands to take place

Successive iterations of halting and resuming the management chip (MCP)
might fail, since currently the driver doesn't wait for these operations to
actually take place.
This patch prevents the driver from moving forward before the operations
are reflected in the state register.

Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/qlogic/qed/qed_mcp.c b/drivers/net/ethernet/qlogic/qed/qed_mcp.c
index bdcacb31d88b267d2022b0a66b58bf4b7385c6e7..5f3dbdc7ff1da0eb4af1b8c4d902c0990921fff6 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_mcp.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_mcp.c
@@ -2109,31 +2109,61 @@ qed_mcp_send_drv_version(struct qed_hwfn *p_hwfn,
        return rc;
 }
 
+/* A maximal 100 msec waiting time for the MCP to halt */
+#define QED_MCP_HALT_SLEEP_MS          10
+#define QED_MCP_HALT_MAX_RETRIES       10
+
 int qed_mcp_halt(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt)
 {
-       u32 resp = 0, param = 0;
+       u32 resp = 0, param = 0, cpu_state, cnt = 0;
        int rc;
 
        rc = qed_mcp_cmd(p_hwfn, p_ptt, DRV_MSG_CODE_MCP_HALT, 0, &resp,
                         &param);
-       if (rc)
+       if (rc) {
                DP_ERR(p_hwfn, "MCP response failure, aborting\n");
+               return rc;
+       }
 
-       return rc;
+       do {
+               msleep(QED_MCP_HALT_SLEEP_MS);
+               cpu_state = qed_rd(p_hwfn, p_ptt, MCP_REG_CPU_STATE);
+               if (cpu_state & MCP_REG_CPU_STATE_SOFT_HALTED)
+                       break;
+       } while (++cnt < QED_MCP_HALT_MAX_RETRIES);
+
+       if (cnt == QED_MCP_HALT_MAX_RETRIES) {
+               DP_NOTICE(p_hwfn,
+                         "Failed to halt the MCP [CPU_MODE = 0x%08x, CPU_STATE = 0x%08x]\n",
+                         qed_rd(p_hwfn, p_ptt, MCP_REG_CPU_MODE), cpu_state);
+               return -EBUSY;
+       }
+
+       return 0;
 }
 
+#define QED_MCP_RESUME_SLEEP_MS        10
+
 int qed_mcp_resume(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt)
 {
-       u32 value, cpu_mode;
+       u32 cpu_mode, cpu_state;
 
        qed_wr(p_hwfn, p_ptt, MCP_REG_CPU_STATE, 0xffffffff);
 
-       value = qed_rd(p_hwfn, p_ptt, MCP_REG_CPU_MODE);
-       value &= ~MCP_REG_CPU_MODE_SOFT_HALT;
-       qed_wr(p_hwfn, p_ptt, MCP_REG_CPU_MODE, value);
        cpu_mode = qed_rd(p_hwfn, p_ptt, MCP_REG_CPU_MODE);
+       cpu_mode &= ~MCP_REG_CPU_MODE_SOFT_HALT;
+       qed_wr(p_hwfn, p_ptt, MCP_REG_CPU_MODE, cpu_mode);
+       msleep(QED_MCP_RESUME_SLEEP_MS);
+       cpu_state = qed_rd(p_hwfn, p_ptt, MCP_REG_CPU_STATE);
 
-       return (cpu_mode & MCP_REG_CPU_MODE_SOFT_HALT) ? -EAGAIN : 0;
+       if (cpu_state & MCP_REG_CPU_STATE_SOFT_HALTED) {
+               DP_NOTICE(p_hwfn,
+                         "Failed to resume the MCP [CPU_MODE = 0x%08x, CPU_STATE = 0x%08x]\n",
+                         cpu_mode, cpu_state);
+               return -EBUSY;
+       }
+
+       return 0;
 }
 
 int qed_mcp_ov_update_current_config(struct qed_hwfn *p_hwfn,

diff --git a/drivers/net/ethernet/qlogic/qed/qed_reg_addr.h b/drivers/net/ethernet/qlogic/qed/qed_reg_addr.h
index d8ad2dcad8d5ef589252eb797556359ebe89fbcb..2279965f8f8a488e24d7c97aaf6153fedf269cfc 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_reg_addr.h
+++ b/drivers/net/ethernet/qlogic/qed/qed_reg_addr.h
@@ -562,6 +562,7 @@
        0
 #define MCP_REG_CPU_STATE \
        0xe05004UL
+#define MCP_REG_CPU_STATE_SOFT_HALTED  (0x1UL << 10)
 #define MCP_REG_CPU_EVENT_MASK \
        0xe05008UL
 #define PGLUE_B_REG_PF_BAR0_SIZE \