iwlwifi: support NVM access (EEPROM/OTP)

Two type of NVM available for devices 1000, 6000 and after, adding
support to read OTP lower blocks if OTP is used instead of EEPROM.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 129 insertions, 18 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
index b400bd510fc..9cc063b8b2d 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
@@ -152,6 +152,32 @@ int iwlcore_eeprom_verify_signature(struct iwl_priv *priv)
 }
 EXPORT_SYMBOL(iwlcore_eeprom_verify_signature);
 
+static int iwlcore_get_nvm_type(struct iwl_priv *priv)
+{
+        u32 otpgp;
+        int nvm_type;
+
+        /* OTP only valid for CP/PP and after */
+        switch (priv->hw_rev & CSR_HW_REV_TYPE_MSK) {
+        case CSR_HW_REV_TYPE_3945:
+        case CSR_HW_REV_TYPE_4965:
+        case CSR_HW_REV_TYPE_5300:
+        case CSR_HW_REV_TYPE_5350:
+        case CSR_HW_REV_TYPE_5100:
+        case CSR_HW_REV_TYPE_5150:
+                nvm_type = NVM_DEVICE_TYPE_EEPROM;
+                break;
+        default:
+                otpgp = iwl_read32(priv, CSR_OTP_GP_REG);
+                if (otpgp & CSR_OTP_GP_REG_DEVICE_SELECT)
+                        nvm_type = NVM_DEVICE_TYPE_OTP;
+                else
+                        nvm_type = NVM_DEVICE_TYPE_EEPROM;
+                break;
+        }
+        return  nvm_type;
+}
+
 /*
  * The device's EEPROM semaphore prevents conflicts between driver and uCode
  * when accessing the EEPROM; each access is a series of pulses to/from the
@@ -198,6 +224,35 @@ const u8 *iwlcore_eeprom_query_addr(const struct iwl_priv *priv, size_t offset)
 }
 EXPORT_SYMBOL(iwlcore_eeprom_query_addr);
 
+static int iwl_init_otp_access(struct iwl_priv *priv)
+{
+        int ret;
+
+        /* Enable 40MHz radio clock */
+        _iwl_write32(priv, CSR_GP_CNTRL,
+                     _iwl_read32(priv, CSR_GP_CNTRL) |
+                     CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
+
+        /* wait for clock to be ready */
+        ret = iwl_poll_direct_bit(priv, CSR_GP_CNTRL,
+                                  CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
+                                  25000);
+        if (ret < 0)
+                IWL_ERR(priv, "Time out access OTP\n");
+        else {
+                ret = iwl_grab_nic_access(priv);
+                if (!ret) {
+                        iwl_set_bits_prph(priv, APMG_PS_CTRL_REG,
+                                          APMG_PS_CTRL_VAL_RESET_REQ);
+                        udelay(5);
+                        iwl_clear_bits_prph(priv, APMG_PS_CTRL_REG,
+                                            APMG_PS_CTRL_VAL_RESET_REQ);
+                        iwl_release_nic_access(priv);
+                }
+        }
+        return ret;
+}
+
 /**
  * iwl_eeprom_init - read EEPROM contents
  *
@@ -209,11 +264,18 @@ int iwl_eeprom_init(struct iwl_priv *priv)
 {
         u16 *e;
         u32 gp = iwl_read32(priv, CSR_EEPROM_GP);
-        int sz = priv->cfg->eeprom_size;
+        int sz;
         int ret;
         u16 addr;
+        u32 otpgp;
+
+        priv->nvm_device_type = iwlcore_get_nvm_type(priv);
 
         /* allocate eeprom */
+        if (priv->nvm_device_type == NVM_DEVICE_TYPE_OTP)
+                priv->cfg->eeprom_size =
+                        OTP_BLOCK_SIZE * OTP_LOWER_BLOCKS_TOTAL;
+        sz = priv->cfg->eeprom_size;
         priv->eeprom = kzalloc(sz, GFP_KERNEL);
         if (!priv->eeprom) {
                 ret = -ENOMEM;
@@ -235,30 +297,77 @@ int iwl_eeprom_init(struct iwl_priv *priv)
                 ret = -ENOENT;
                 goto err;
         }
-
-        /* eeprom is an array of 16bit values */
-        for (addr = 0; addr < sz; addr += sizeof(u16)) {
-                u32 r;
-
-                _iwl_write32(priv, CSR_EEPROM_REG,
-                             CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
-
-                ret = iwl_poll_direct_bit(priv, CSR_EEPROM_REG,
-                                          CSR_EEPROM_REG_READ_VALID_MSK,
-                                          IWL_EEPROM_ACCESS_TIMEOUT);
-                if (ret < 0) {
-                        IWL_ERR(priv, "Time out reading EEPROM[%d]\n", addr);
-                        goto done;
+        if (priv->nvm_device_type == NVM_DEVICE_TYPE_OTP) {
+                ret = iwl_init_otp_access(priv);
+                if (ret) {
+                        IWL_ERR(priv, "Failed to initialize OTP access.\n");
+                        ret = -ENOENT;
+                        goto err;
+                }
+                _iwl_write32(priv, CSR_EEPROM_GP,
+                             iwl_read32(priv, CSR_EEPROM_GP) &
+                             ~CSR_EEPROM_GP_IF_OWNER_MSK);
+                /* clear */
+                _iwl_write32(priv, CSR_OTP_GP_REG,
+                             iwl_read32(priv, CSR_OTP_GP_REG) |
+                             CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK |
+                             CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
+
+                for (addr = 0; addr < sz; addr += sizeof(u16)) {
+                        u32 r;
+
+                        _iwl_write32(priv, CSR_EEPROM_REG,
+                                     CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
+
+                        ret = iwl_poll_direct_bit(priv, CSR_EEPROM_REG,
+                                                  CSR_EEPROM_REG_READ_VALID_MSK,
+                                                  IWL_EEPROM_ACCESS_TIMEOUT);
+                        if (ret < 0) {
+                                IWL_ERR(priv, "Time out reading OTP[%d]\n", addr);
+                                goto done;
+                        }
+                        r = _iwl_read_direct32(priv, CSR_EEPROM_REG);
+                        /* check for ECC errors: */
+                        otpgp = iwl_read32(priv, CSR_OTP_GP_REG);
+                        if (otpgp & CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK) {
+                                /* stop in this case */
+                                IWL_ERR(priv, "Uncorrectable OTP ECC error, Abort OTP read\n");
+                                goto done;
+                        }
+                        if (otpgp & CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK) {
+                                /* continue in this case */
+                                _iwl_write32(priv, CSR_OTP_GP_REG,
+                                             iwl_read32(priv, CSR_OTP_GP_REG) |
+                                             CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK);
+                                IWL_ERR(priv, "Correctable OTP ECC error, continue read\n");
+                        }
+                        e[addr / 2] = le16_to_cpu((__force __le16)(r >> 16));
+                }
+        } else {
+                /* eeprom is an array of 16bit values */
+                for (addr = 0; addr < sz; addr += sizeof(u16)) {
+                        u32 r;
+
+                        _iwl_write32(priv, CSR_EEPROM_REG,
+                                     CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
+
+                        ret = iwl_poll_direct_bit(priv, CSR_EEPROM_REG,
+                                                  CSR_EEPROM_REG_READ_VALID_MSK,
+                                                  IWL_EEPROM_ACCESS_TIMEOUT);
+                        if (ret < 0) {
+                                IWL_ERR(priv, "Time out reading EEPROM[%d]\n", addr);
+                                goto done;
+                        }
+                        r = _iwl_read_direct32(priv, CSR_EEPROM_REG);
+                        e[addr / 2] = le16_to_cpu((__force __le16)(r >> 16));
                 }
-                r = _iwl_read_direct32(priv, CSR_EEPROM_REG);
-                e[addr / 2] = le16_to_cpu((__force __le16)(r >> 16));
         }
         ret = 0;
 done:
         priv->cfg->ops->lib->eeprom_ops.release_semaphore(priv);
 err:
         if (ret)
-                kfree(priv->eeprom);
+                iwl_eeprom_free(priv);
 alloc_err:
         return ret;
 }
@@ -301,6 +410,8 @@ EXPORT_SYMBOL(iwl_eeprom_query_addr);
 
 u16 iwl_eeprom_query16(const struct iwl_priv *priv, size_t offset)
 {
+        if (!priv->eeprom)
+                return 0;
         return (u16)priv->eeprom[offset] | ((u16)priv->eeprom[offset + 1] << 8);
 }
 EXPORT_SYMBOL(iwl_eeprom_query16);