/** * Change transfer frequency for an SD card * @param mci MCI instance * @return Transaction status (0 on success) */ static int sd_change_freq(struct mci *mci) { struct mci_cmd cmd; struct mci_data data; #ifdef CONFIG_MCI_SPI struct mci_host *host = mci->host; #endif uint32_t *switch_status = sector_buf; uint32_t *scr = sector_buf; int timeout; int err; if (mmc_host_is_spi(host)) return 0; dev_dbg(mci->mci_dev, "Changing transfer frequency\n"); mci->card_caps = 0; /* Read the SCR to find out if this card supports higher speeds */ mci_setup_cmd(&cmd, MMC_CMD_APP_CMD, mci->rca << 16, MMC_RSP_R1); err = mci_send_cmd(mci, &cmd, NULL); if (err) { dev_dbg(mci->mci_dev, "Query SD card capabilities failed: %d\n", err); return err; } mci_setup_cmd(&cmd, SD_CMD_APP_SEND_SCR, 0, MMC_RSP_R1); timeout = 3; retry_scr: dev_dbg(mci->mci_dev, "Trying to read the SCR (try %d of %d)\n", 4 - timeout, 3); data.dest = (char *)scr; data.blocksize = 8; data.blocks = 1; data.flags = MMC_DATA_READ; err = mci_send_cmd(mci, &cmd, &data); if (err) { dev_dbg(mci->mci_dev, " Catch error (%d)", err); if (timeout--) { dev_dbg(mci->mci_dev, "-- retrying\n"); goto retry_scr; } dev_dbg(mci->mci_dev, "-- giving up\n"); return err; } mci->scr[0] = __be32_to_cpu(scr[0]); mci->scr[1] = __be32_to_cpu(scr[1]); switch ((mci->scr[0] >> 24) & 0xf) { case 0: mci->version = SD_VERSION_1_0; break; case 1: mci->version = SD_VERSION_1_10; break; case 2: mci->version = SD_VERSION_2; break; default: mci->version = SD_VERSION_1_0; break; } /* Version 1.0 doesn't support switching */ if (mci->version == SD_VERSION_1_0) return 0; timeout = 4; while (timeout--) { err = sd_switch(mci, SD_SWITCH_CHECK, 0, 1, (uint8_t*)switch_status); if (err) { dev_dbg(mci->mci_dev, "Checking SD transfer switch frequency feature failed: %d\n", err); return err; } /* The high-speed function is busy. Try again */ if (!(__be32_to_cpu(switch_status[7]) & SD_HIGHSPEED_BUSY)) break; } if (mci->scr[0] & SD_DATA_4BIT) mci->card_caps |= MMC_MODE_4BIT; /* If high-speed isn't supported, we return */ if (!(__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED)) return 0; err = sd_switch(mci, SD_SWITCH_SWITCH, 0, 1, (uint8_t*)switch_status); if (err) { dev_dbg(mci->mci_dev, "Switching SD transfer frequency failed: %d\n", err); return err; } if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) == 0x01000000) mci->card_caps |= MMC_MODE_HS; return 0; }
int sd_change_freq(struct mmc *mmc) { int err; struct mmc_cmd cmd; u32 scr[2]; u32 switch_status[16]; struct mmc_data data; int timeout; mmc->card_caps = 0; if (mmc_host_is_spi(mmc)) return 0; /* Read the SCR to find out if this card supports higher speeds */ cmd.cmdidx = MMC_CMD_APP_CMD; cmd.resp_type = MMC_RSP_R1; cmd.cmdarg = mmc->rca << 16; cmd.flags = 0; err = mmc_send_cmd(mmc, &cmd, NULL); if (err){ mmcinfo("mmc %d Send app cmd failed\n",mmc->control_num); return err; } cmd.cmdidx = SD_CMD_APP_SEND_SCR; cmd.resp_type = MMC_RSP_R1; cmd.cmdarg = 0; cmd.flags = 0; timeout = 3; retry_scr: data.b.dest = (char *)&scr; data.blocksize = 8; data.blocks = 1; data.flags = MMC_DATA_READ; err = mmc_send_cmd(mmc, &cmd, &data); if (err) { if (timeout--) goto retry_scr; mmcinfo("mmc %d Send scr failed\n",mmc->control_num); return err; } mmc->scr[0] = __be32_to_cpu(scr[0]); mmc->scr[1] = __be32_to_cpu(scr[1]); switch ((mmc->scr[0] >> 24) & 0xf) { case 0: mmc->version = SD_VERSION_1_0; break; case 1: mmc->version = SD_VERSION_1_10; break; case 2: mmc->version = SD_VERSION_2; break; default: mmc->version = SD_VERSION_1_0; break; } if (mmc->scr[0] & SD_DATA_4BIT) mmc->card_caps |= MMC_MODE_4BIT; /* Version 1.0 doesn't support switching */ if (mmc->version == SD_VERSION_1_0) return 0; timeout = 4; while (timeout--) { err = sd_switch(mmc, SD_SWITCH_CHECK, 0, 1, (u8 *)&switch_status); if (err){ mmcinfo("mmc %d Check high speed status faild\n",mmc->control_num); return err; } /* The high-speed function is busy. Try again */ if (!(__be32_to_cpu(switch_status[7]) & SD_HIGHSPEED_BUSY)) break; } /* If high-speed isn't supported, we return */ if (!(__be32_to_cpu(switch_status[3]) & SD_HIGHSPEED_SUPPORTED)) return 0; err = sd_switch(mmc, SD_SWITCH_SWITCH, 0, 1, (u8 *)&switch_status); if (err){ mmcinfo("mmc %d switch to high speed failed\n",mmc->control_num); return err; } if ((__be32_to_cpu(switch_status[4]) & 0x0f000000) == 0x01000000) mmc->card_caps |= MMC_MODE_HS; return 0; }