This core driver will be used by a MIPS platform driver
or by an ARM64 PCI driver. The core driver implements the
mmc_host_ops and slot probe & remove functions.
Callbacks are provided to allow platform specific interrupt
enable and bus locking.

The host controller supports:
- up to 4 slots that can contain sd-cards or eMMC chips
- 1, 4 and 8 bit bus width
- SDR and DDR
- transfers up to 52 Mhz (might be less when multiple slots are used)
- DMA read/write
- multi-block read/write (but not stream mode)

Voltage is limited to 3.3v and shared for all slots.

A global lock for all MMC devices is required because the host
controller is shared.

Signed-off-by: Jan Glauber <jglau...@cavium.com>
---
 drivers/mmc/host/cavium_core_mmc.c | 1008 ++++++++++++++++++++++++++++++++++++
 drivers/mmc/host/cavium_mmc.h      |  303 +++++++++++
 2 files changed, 1311 insertions(+)
 create mode 100644 drivers/mmc/host/cavium_core_mmc.c
 create mode 100644 drivers/mmc/host/cavium_mmc.h

diff --git a/drivers/mmc/host/cavium_core_mmc.c 
b/drivers/mmc/host/cavium_core_mmc.c
new file mode 100644
index 0000000..89d23d3
--- /dev/null
+++ b/drivers/mmc/host/cavium_core_mmc.c
@@ -0,0 +1,1008 @@
+/*
+ * Shared part of driver for MMC/SDHC controller on Cavium OCTEON and
+ * ThunderX SOCs.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012-2016 Cavium Inc.
+ * Authors:
+ *   David Daney <david.da...@cavium.com>
+ *   Peter Swain <psw...@cavium.com>
+ *   Steven J. Hill <steven.h...@cavium.com>
+ *   Jan Glauber <jglau...@cavium.com>
+ */
+#include <linux/delay.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/slot-gpio.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/time.h>
+
+#include "cavium_mmc.h"
+
+/*
+ * The Cavium MMC host hardware assumes that all commands have fixed
+ * command and response types.  These are correct if MMC devices are
+ * being used.  However, non-MMC devices like SD use command and
+ * response types that are unexpected by the host hardware.
+ *
+ * The command and response types can be overridden by supplying an
+ * XOR value that is applied to the type.  We calculate the XOR value
+ * from the values in this table and the flags passed from the MMC
+ * core.
+ */
+static struct cvm_mmc_cr_type cvm_mmc_cr_types[] = {
+       {0, 0},         /* CMD0 */
+       {0, 3},         /* CMD1 */
+       {0, 2},         /* CMD2 */
+       {0, 1},         /* CMD3 */
+       {0, 0},         /* CMD4 */
+       {0, 1},         /* CMD5 */
+       {0, 1},         /* CMD6 */
+       {0, 1},         /* CMD7 */
+       {1, 1},         /* CMD8 */
+       {0, 2},         /* CMD9 */
+       {0, 2},         /* CMD10 */
+       {1, 1},         /* CMD11 */
+       {0, 1},         /* CMD12 */
+       {0, 1},         /* CMD13 */
+       {1, 1},         /* CMD14 */
+       {0, 0},         /* CMD15 */
+       {0, 1},         /* CMD16 */
+       {1, 1},         /* CMD17 */
+       {1, 1},         /* CMD18 */
+       {3, 1},         /* CMD19 */
+       {2, 1},         /* CMD20 */
+       {0, 0},         /* CMD21 */
+       {0, 0},         /* CMD22 */
+       {0, 1},         /* CMD23 */
+       {2, 1},         /* CMD24 */
+       {2, 1},         /* CMD25 */
+       {2, 1},         /* CMD26 */
+       {2, 1},         /* CMD27 */
+       {0, 1},         /* CMD28 */
+       {0, 1},         /* CMD29 */
+       {1, 1},         /* CMD30 */
+       {1, 1},         /* CMD31 */
+       {0, 0},         /* CMD32 */
+       {0, 0},         /* CMD33 */
+       {0, 0},         /* CMD34 */
+       {0, 1},         /* CMD35 */
+       {0, 1},         /* CMD36 */
+       {0, 0},         /* CMD37 */
+       {0, 1},         /* CMD38 */
+       {0, 4},         /* CMD39 */
+       {0, 5},         /* CMD40 */
+       {0, 0},         /* CMD41 */
+       {2, 1},         /* CMD42 */
+       {0, 0},         /* CMD43 */
+       {0, 0},         /* CMD44 */
+       {0, 0},         /* CMD45 */
+       {0, 0},         /* CMD46 */
+       {0, 0},         /* CMD47 */
+       {0, 0},         /* CMD48 */
+       {0, 0},         /* CMD49 */
+       {0, 0},         /* CMD50 */
+       {0, 0},         /* CMD51 */
+       {0, 0},         /* CMD52 */
+       {0, 0},         /* CMD53 */
+       {0, 0},         /* CMD54 */
+       {0, 1},         /* CMD55 */
+       {0xff, 0xff},   /* CMD56 */
+       {0, 0},         /* CMD57 */
+       {0, 0},         /* CMD58 */
+       {0, 0},         /* CMD59 */
+       {0, 0},         /* CMD60 */
+       {0, 0},         /* CMD61 */
+       {0, 0},         /* CMD62 */
+       {0, 0}          /* CMD63 */
+};
+
+static struct cvm_mmc_cr_mods cvm_mmc_get_cr_mods(struct mmc_command *cmd)
+{
+       struct cvm_mmc_cr_type *cr;
+       u8 hardware_ctype, hardware_rtype;
+       u8 desired_ctype = 0, desired_rtype = 0;
+       struct cvm_mmc_cr_mods r;
+
+       cr = cvm_mmc_cr_types + (cmd->opcode & 0x3f);
+       hardware_ctype = cr->ctype;
+       hardware_rtype = cr->rtype;
+       if (cmd->opcode == MMC_GEN_CMD)
+               hardware_ctype = (cmd->arg & 1) ? 1 : 2;
+
+       switch (mmc_cmd_type(cmd)) {
+       case MMC_CMD_ADTC:
+               desired_ctype = (cmd->data->flags & MMC_DATA_WRITE) ? 2 : 1;
+               break;
+       case MMC_CMD_AC:
+       case MMC_CMD_BC:
+       case MMC_CMD_BCR:
+               desired_ctype = 0;
+               break;
+       }
+
+       switch (mmc_resp_type(cmd)) {
+       case MMC_RSP_NONE:
+               desired_rtype = 0;
+               break;
+       case MMC_RSP_R1:/* MMC_RSP_R5, MMC_RSP_R6, MMC_RSP_R7 */
+       case MMC_RSP_R1B:
+               desired_rtype = 1;
+               break;
+       case MMC_RSP_R2:
+               desired_rtype = 2;
+               break;
+       case MMC_RSP_R3: /* MMC_RSP_R4 */
+               desired_rtype = 3;
+               break;
+       }
+       r.ctype_xor = desired_ctype ^ hardware_ctype;
+       r.rtype_xor = desired_rtype ^ hardware_rtype;
+       return r;
+}
+
+static void check_switch_errors(struct cvm_mmc_host *host)
+{
+       union mio_emm_switch emm_switch;
+
+       emm_switch.val = readq(host->base + MIO_EMM_SWITCH);
+       if (emm_switch.s.switch_err0)
+               dev_err(host->dev, "Switch power class error\n");
+       if (emm_switch.s.switch_err1)
+               dev_err(host->dev, "Switch hs timing error\n");
+       if (emm_switch.s.switch_err2)
+               dev_err(host->dev, "Switch bus width error\n");
+}
+
+/*
+ * We never set the switch_exe bit since that would interfere
+ * with the commands send by the MMC core.
+ */
+static void do_switch(struct cvm_mmc_host *host, u64 val)
+{
+       union mio_emm_rsp_sts rsp_sts;
+       union mio_emm_switch emm_switch;
+       int retries = 100;
+       int bus_id;
+
+       emm_switch.val = val;
+
+       /*
+        * Modes setting only taken from slot 0. Work around that hardware
+        * issue by first switching to slot 0.
+        */
+       bus_id = emm_switch.s.bus_id;
+       emm_switch.s.bus_id = 0;
+       writeq(emm_switch.val, host->base + MIO_EMM_SWITCH);
+
+       emm_switch.s.bus_id = bus_id;
+       writeq(emm_switch.val, host->base + MIO_EMM_SWITCH);
+
+       /* wait for the switch to finish */
+       do {
+               rsp_sts.val = readq(host->base + MIO_EMM_RSP_STS);
+               if (!rsp_sts.s.switch_val)
+                       break;
+               udelay(10);
+       } while (--retries);
+
+       check_switch_errors(host);
+}
+
+static bool switch_val_changed(struct cvm_mmc_slot *slot, u64 new_val)
+{
+       /* Match BUS_ID, HS_TIMING, BUS_WIDTH, POWER_CLASS, CLK_HI, CLK_LO */
+       u64 match = 0x3001070fffffffffull;
+
+       return (slot->cached_switch & match) != (new_val & match);
+}
+
+static void set_wdog(struct cvm_mmc_slot *slot, unsigned int ns)
+{
+       u64 timeout;
+
+       WARN_ON_ONCE(!slot->clock);
+       if (ns)
+               timeout = (slot->clock * ns) / NSEC_PER_SEC;
+       else
+               timeout = (slot->clock * 850ull) / 1000ull;
+       writeq(timeout, slot->host->base + MIO_EMM_WDOG);
+}
+
+static void cvm_mmc_reset_bus(struct cvm_mmc_slot *slot)
+{
+       union mio_emm_switch emm_switch;
+       u64 wdog = 0;
+
+       emm_switch.val = readq(slot->host->base + MIO_EMM_SWITCH);
+       wdog = readq(slot->host->base + MIO_EMM_WDOG);
+
+       emm_switch.s.switch_exe = 0;
+       emm_switch.s.switch_err0 = 0;
+       emm_switch.s.switch_err1 = 0;
+       emm_switch.s.switch_err2 = 0;
+       emm_switch.s.bus_id = slot->bus_id;
+       do_switch(slot->host, emm_switch.val);
+
+       slot->cached_switch = emm_switch.val;
+
+       msleep(20);
+
+       writeq(wdog, slot->host->base + MIO_EMM_WDOG);
+}
+
+/* Switch to another slot if needed */
+static void cvm_mmc_switch_to(struct cvm_mmc_slot *slot)
+{
+       struct cvm_mmc_host *host = slot->host;
+       struct cvm_mmc_slot *old_slot;
+       union mio_emm_switch emm_switch;
+       union mio_emm_sample emm_sample;
+
+       if (slot->bus_id == host->last_slot)
+               return;
+
+       if (host->last_slot >= 0 && host->slot[host->last_slot]) {
+               old_slot = host->slot[host->last_slot];
+               old_slot->cached_switch = readq(host->base + MIO_EMM_SWITCH);
+               old_slot->cached_rca = readq(host->base + MIO_EMM_RCA);
+       }
+
+       writeq(slot->cached_rca, host->base + MIO_EMM_RCA);
+       emm_switch.val = slot->cached_switch;
+       emm_switch.s.bus_id = slot->bus_id;
+       do_switch(host, emm_switch.val);
+
+       emm_sample.val = 0;
+       emm_sample.s.cmd_cnt = slot->cmd_cnt;
+       emm_sample.s.dat_cnt = slot->dat_cnt;
+       writeq(emm_sample.val, host->base + MIO_EMM_SAMPLE);
+
+       host->last_slot = slot->bus_id;
+}
+
+static void do_read(struct cvm_mmc_host *host, struct mmc_request *req,
+                   u64 dbuf)
+{
+       struct sg_mapping_iter *smi = &host->smi;
+       int data_len = req->data->blocks * req->data->blksz;
+       int bytes_xfered, shift = -1;
+       u64 dat = 0;
+
+       /* Auto inc from offset zero */
+       writeq((0x10000 | (dbuf << 6)), host->base + MIO_EMM_BUF_IDX);
+
+       for (bytes_xfered = 0; bytes_xfered < data_len;) {
+               if (smi->consumed >= smi->length) {
+                       if (!sg_miter_next(smi))
+                               break;
+                       smi->consumed = 0;
+               }
+
+               if (shift < 0) {
+                       dat = readq(host->base + MIO_EMM_BUF_DAT);
+                       shift = 56;
+               }
+
+               while (smi->consumed < smi->length && shift >= 0) {
+                       ((u8 *)smi->addr)[smi->consumed] = (dat >> shift) & 
0xff;
+                       bytes_xfered++;
+                       smi->consumed++;
+                       shift -= 8;
+               }
+       }
+
+       sg_miter_stop(smi);
+       req->data->bytes_xfered = bytes_xfered;
+       req->data->error = 0;
+}
+
+static void do_write(struct mmc_request *req)
+{
+       req->data->bytes_xfered = req->data->blocks * req->data->blksz;
+       req->data->error = 0;
+}
+
+static void set_cmd_response(struct cvm_mmc_host *host, struct mmc_request 
*req,
+                            union mio_emm_rsp_sts *rsp_sts)
+{
+       u64 rsp_hi, rsp_lo;
+
+       if (!rsp_sts->s.rsp_val)
+               return;
+
+       rsp_lo = readq(host->base + MIO_EMM_RSP_LO);
+
+       switch (rsp_sts->s.rsp_type) {
+       case 1:
+       case 3:
+               req->cmd->resp[0] = (rsp_lo >> 8) & 0xffffffff;
+               req->cmd->resp[1] = 0;
+               req->cmd->resp[2] = 0;
+               req->cmd->resp[3] = 0;
+               break;
+       case 2:
+               req->cmd->resp[3] = rsp_lo & 0xffffffff;
+               req->cmd->resp[2] = (rsp_lo >> 32) & 0xffffffff;
+               rsp_hi = readq(host->base + MIO_EMM_RSP_HI);
+               req->cmd->resp[1] = rsp_hi & 0xffffffff;
+               req->cmd->resp[0] = (rsp_hi >> 32) & 0xffffffff;
+               break;
+       }
+}
+
+static int get_dma_dir(struct mmc_data *data)
+{
+       return (data->flags & MMC_DATA_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+}
+
+static int finish_dma_single(struct cvm_mmc_host *host, struct mmc_data *data)
+{
+       data->bytes_xfered = data->blocks * data->blksz;
+       data->error = 0;
+       return 1;
+}
+
+static int finish_dma(struct cvm_mmc_host *host, struct mmc_data *data)
+{
+       return finish_dma_single(host, data);
+}
+
+static bool bad_status(union mio_emm_rsp_sts *rsp_sts)
+{
+       if (rsp_sts->s.rsp_bad_sts || rsp_sts->s.rsp_crc_err ||
+           rsp_sts->s.rsp_timeout || rsp_sts->s.blk_crc_err ||
+           rsp_sts->s.blk_timeout || rsp_sts->s.dbuf_err)
+               return true;
+
+       return false;
+}
+
+/* Try to clean up failed DMA. */
+static void cleanup_dma(struct cvm_mmc_host *host,
+                       union mio_emm_rsp_sts *rsp_sts)
+{
+       union mio_emm_dma emm_dma;
+
+       emm_dma.val = readq(host->base + MIO_EMM_DMA);
+       emm_dma.s.dma_val = 1;
+       emm_dma.s.dat_null = 1;
+       emm_dma.s.bus_id = rsp_sts->s.bus_id;
+       writeq(emm_dma.val, host->base + MIO_EMM_DMA);
+}
+
+irqreturn_t cvm_mmc_interrupt(int irq, void *dev_id)
+{
+       struct cvm_mmc_host *host = dev_id;
+       union mio_emm_rsp_sts rsp_sts;
+       union mio_emm_int emm_int;
+       struct mmc_request *req;
+       bool host_done;
+
+       /* Clear interrupt bits (write 1 clears ). */
+       emm_int.val = readq(host->base + MIO_EMM_INT);
+       writeq(emm_int.val, host->base + MIO_EMM_INT);
+
+       if (emm_int.s.switch_err)
+               check_switch_errors(host);
+
+       req = host->current_req;
+       if (!req)
+               goto out;
+
+       rsp_sts.val = readq(host->base + MIO_EMM_RSP_STS);
+       /*
+        * dma_val set means DMA is still in progress. Don't touch
+        * the request and wait for the interrupt indicating that
+        * the DMA is finished.
+        */
+       if (rsp_sts.s.dma_val && host->dma_active)
+               goto out;
+
+       if (!host->dma_active && emm_int.s.buf_done && req->data) {
+               unsigned int type = (rsp_sts.val >> 7) & 3;
+
+               if (type == 1)
+                       do_read(host, req, rsp_sts.s.dbuf);
+               else if (type == 2)
+                       do_write(req);
+       }
+
+       host_done = emm_int.s.cmd_done || emm_int.s.dma_done ||
+                   emm_int.s.cmd_err || emm_int.s.dma_err;
+
+       if (!(host_done && req->done))
+               goto no_req_done;
+
+       if (bad_status(&rsp_sts))
+               req->cmd->error = -EILSEQ;
+       else
+               req->cmd->error = 0;
+
+       if (host->dma_active && req->data)
+               if (!finish_dma(host, req->data))
+                       goto no_req_done;
+
+       set_cmd_response(host, req, &rsp_sts);
+       if (emm_int.s.dma_err && rsp_sts.s.dma_pend)
+               cleanup_dma(host, &rsp_sts);
+
+       host->current_req = NULL;
+       req->done(req);
+
+no_req_done:
+       if (host_done)
+               host->release_bus(host);
+out:
+       return IRQ_RETVAL(emm_int.val != 0);
+}
+
+/*
+ * Program DMA_CFG and if needed DMA_ADR.
+ * Returns 0 on error, DMA address otherwise.
+ */
+static u64 prepare_dma_single(struct cvm_mmc_host *host, struct mmc_data *data)
+{
+       union mio_emm_dma_cfg dma_cfg;
+       int count;
+       u64 addr;
+
+       count = dma_map_sg(host->dev, data->sg, data->sg_len,
+                          get_dma_dir(data));
+       if (!count)
+               return 0;
+
+       dma_cfg.val = 0;
+       dma_cfg.s.en = 1;
+       dma_cfg.s.rw = (data->flags & MMC_DATA_WRITE) ? 1 : 0;
+#ifdef __LITTLE_ENDIAN
+       dma_cfg.s.endian = 1;
+#endif
+       dma_cfg.s.size = (sg_dma_len(&data->sg[0]) / 8) - 1;
+
+       addr = sg_dma_address(&data->sg[0]);
+       dma_cfg.s.adr = addr;
+       writeq(dma_cfg.val, host->dma_base + MIO_EMM_DMA_CFG);
+
+       pr_debug("[%s] sg_dma_len: %u  total sg_elem: %d\n",
+                (dma_cfg.s.rw) ? "W" : "R", sg_dma_len(&data->sg[0]), count);
+       return addr;
+}
+
+static u64 prepare_dma(struct cvm_mmc_host *host, struct mmc_data *data)
+{
+       return prepare_dma_single(host, data);
+}
+
+static void prepare_ext_dma(struct mmc_host *mmc, struct mmc_request *mrq,
+                           union mio_emm_dma *emm_dma)
+{
+       struct cvm_mmc_slot *slot = mmc_priv(mmc);
+
+       /*
+        * Our MMC host hardware does not issue single commands,
+        * because that would require the driver and the MMC core
+        * to do work to determine the proper sequence of commands.
+        * Instead, our hardware is superior to most other MMC bus
+        * hosts. The sequence of MMC commands required to execute
+        * a transfer are issued automatically by the bus hardware.
+        *
+        * - David Daney <dda...@cavium.com>
+        */
+       emm_dma->val = 0;
+       emm_dma->s.bus_id = slot->bus_id;
+       emm_dma->s.dma_val = 1;
+       emm_dma->s.sector = mmc_card_blockaddr(mmc->card) ? 1 : 0;
+       emm_dma->s.rw = (mrq->data->flags & MMC_DATA_WRITE) ? 1 : 0;
+       emm_dma->s.block_cnt = mrq->data->blocks;
+       emm_dma->s.card_addr = mrq->cmd->arg;
+       if (mmc_card_mmc(mmc->card) || (mmc_card_sd(mmc->card) &&
+           (mmc->card->scr.cmds & SD_SCR_CMD23_SUPPORT)))
+               emm_dma->s.multi = 1;
+
+       pr_debug("[%s] blocks: %u  multi: %d\n", (emm_dma->s.rw) ? "W" : "R",
+                mrq->data->blocks, emm_dma->s.multi);
+}
+
+static void prepare_emm_int(union mio_emm_int *emm_int)
+{
+       emm_int->val = 0;
+       emm_int->s.cmd_err = 1;
+       emm_int->s.dma_done = 1;
+       emm_int->s.dma_err = 1;
+}
+
+static void cvm_mmc_dma_request(struct mmc_host *mmc,
+                               struct mmc_request *mrq)
+{
+       struct cvm_mmc_slot *slot = mmc_priv(mmc);
+       struct cvm_mmc_host *host = slot->host;
+       union mio_emm_dma emm_dma;
+       union mio_emm_int emm_int;
+       struct mmc_data *data;
+       u64 addr;
+
+       if (!mrq->data || !mrq->data->sg || !mrq->data->sg_len ||
+           !mrq->stop || mrq->stop->opcode != MMC_STOP_TRANSMISSION) {
+               dev_err(&mmc->card->dev,
+                       "Error: cmv_mmc_dma_request no data\n");
+               goto error;
+       }
+
+       cvm_mmc_switch_to(slot);
+
+       data = mrq->data;
+       pr_debug("DMA request  blocks: %d  block_size: %d  total_size: %d\n",
+                data->blocks, data->blksz, data->blocks * data->blksz);
+       if (data->timeout_ns)
+               set_wdog(slot, data->timeout_ns);
+
+       WARN_ON(host->current_req);
+       host->current_req = mrq;
+
+       prepare_ext_dma(mmc, mrq, &emm_dma);
+       addr = prepare_dma(host, data);
+       if (!addr) {
+               dev_err(host->dev, "prepare_dma failed\n");
+               goto error;
+       }
+       prepare_emm_int(&emm_int);
+
+       host->dma_active = true;
+       host->int_enable(host, emm_int.val);
+
+       /*
+        * If we have a valid SD card in the slot, we set the response
+        * bit mask to check for CRC errors and timeouts only.
+        * Otherwise, use the default power reset value.
+        */
+       if (mmc->card && mmc_card_sd(mmc->card))
+               writeq(0x00b00000ull, host->base + MIO_EMM_STS_MASK);
+       else
+               writeq(0xe4390080ull, host->base + MIO_EMM_STS_MASK);
+       writeq(emm_dma.val, host->base + MIO_EMM_DMA);
+       return;
+
+error:
+       mrq->cmd->error = -EINVAL;
+       if (mrq->done)
+               mrq->done(mrq);
+       host->release_bus(host);
+}
+
+static void do_read_request(struct cvm_mmc_host *host, struct mmc_request *mrq)
+{
+       sg_miter_start(&host->smi, mrq->data->sg, mrq->data->sg_len,
+                      SG_MITER_ATOMIC | SG_MITER_TO_SG);
+}
+
+static void do_write_request(struct cvm_mmc_host *host, struct mmc_request 
*mrq)
+{
+       unsigned int data_len = mrq->data->blocks * mrq->data->blksz;
+       struct sg_mapping_iter *smi = &host->smi;
+       unsigned int bytes_xfered;
+       int shift = 56;
+       u64 dat = 0;
+
+       /* Copy data to the xmit buffer before issuing the command. */
+       sg_miter_start(smi, mrq->data->sg, mrq->data->sg_len, SG_MITER_FROM_SG);
+
+       /* Auto inc from offset zero, dbuf zero */
+       writeq(0x10000ull, host->base + MIO_EMM_BUF_IDX);
+
+       for (bytes_xfered = 0; bytes_xfered < data_len;) {
+               if (smi->consumed >= smi->length) {
+                       if (!sg_miter_next(smi))
+                               break;
+                       smi->consumed = 0;
+               }
+
+               while (smi->consumed < smi->length && shift >= 0) {
+                       dat |= ((u8 *)smi->addr)[smi->consumed] << shift;
+                       bytes_xfered++;
+                       smi->consumed++;
+                       shift -= 8;
+               }
+
+               if (shift < 0) {
+                       writeq(dat, host->base + MIO_EMM_BUF_DAT);
+                       shift = 56;
+                       dat = 0;
+               }
+       }
+       sg_miter_stop(smi);
+}
+
+static void cvm_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+       struct cvm_mmc_slot *slot = mmc_priv(mmc);
+       struct cvm_mmc_host *host = slot->host;
+       struct mmc_command *cmd = mrq->cmd;
+       union mio_emm_int emm_int;
+       union mio_emm_cmd emm_cmd;
+       struct cvm_mmc_cr_mods mods;
+       union mio_emm_rsp_sts rsp_sts;
+       int retries = 100;
+
+       /*
+        * Note about locking:
+        * All MMC devices share the same bus and controller. Allow only a
+        * single user of the bootbus/MMC bus at a time. The lock is acquired
+        * on all entry points from the MMC layer.
+        *
+        * For requests the lock is only released after the completion
+        * interrupt!
+        */
+       host->acquire_bus(host);
+
+       if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
+           cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)
+               return cvm_mmc_dma_request(mmc, mrq);
+
+       cvm_mmc_switch_to(slot);
+
+       mods = cvm_mmc_get_cr_mods(cmd);
+
+       WARN_ON(host->current_req);
+       host->current_req = mrq;
+
+       emm_int.val = 0;
+       emm_int.s.cmd_done = 1;
+       emm_int.s.cmd_err = 1;
+
+       if (cmd->data) {
+               if (cmd->data->flags & MMC_DATA_READ)
+                       do_read_request(host, mrq);
+               else
+                       do_write_request(host, mrq);
+
+               if (cmd->data->timeout_ns)
+                       set_wdog(slot, cmd->data->timeout_ns);
+       } else
+               set_wdog(slot, 0);
+
+       host->dma_active = false;
+       host->int_enable(host, emm_int.val);
+
+       emm_cmd.val = 0;
+       emm_cmd.s.cmd_val = 1;
+       emm_cmd.s.ctype_xor = mods.ctype_xor;
+       emm_cmd.s.rtype_xor = mods.rtype_xor;
+       if (mmc_cmd_type(cmd) == MMC_CMD_ADTC)
+               emm_cmd.s.offset = 64 - ((cmd->data->blocks * cmd->data->blksz) 
/ 8);
+       emm_cmd.s.bus_id = slot->bus_id;
+       emm_cmd.s.cmd_idx = cmd->opcode;
+       emm_cmd.s.arg = cmd->arg;
+
+       writeq(0, host->base + MIO_EMM_STS_MASK);
+
+retry:
+       rsp_sts.val = readq(host->base + MIO_EMM_RSP_STS);
+       if (rsp_sts.s.dma_val || rsp_sts.s.cmd_val ||
+           rsp_sts.s.switch_val || rsp_sts.s.dma_pend) {
+               udelay(10);
+               if (--retries)
+                       goto retry;
+       }
+       if (!retries)
+               dev_err(host->dev, "Bad status: %Lx before command write\n", 
rsp_sts.val);
+       writeq(emm_cmd.val, host->base + MIO_EMM_CMD);
+}
+
+static void cvm_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+       struct cvm_mmc_slot *slot = mmc_priv(mmc);
+       struct cvm_mmc_host *host = slot->host;
+       int clk_period, power_class = 10, bus_width = 0;
+       union mio_emm_switch emm_switch;
+       u64 clock;
+
+       host->acquire_bus(host);
+       cvm_mmc_switch_to(slot);
+
+       /* Reset the chip on each POWER_OFF. */
+       if (ios->power_mode == MMC_POWER_OFF) {
+               cvm_mmc_reset_bus(slot);
+               gpiod_set_value_cansleep(host->global_pwr_gpiod, 0);
+       } else
+               gpiod_set_value_cansleep(host->global_pwr_gpiod, 1);
+
+       switch (ios->bus_width) {
+       case MMC_BUS_WIDTH_8:
+               bus_width = 2;
+               break;
+       case MMC_BUS_WIDTH_4:
+               bus_width = 1;
+               break;
+       case MMC_BUS_WIDTH_1:
+               bus_width = 0;
+               break;
+       }
+
+       slot->bus_width = bus_width;
+
+       if (!ios->clock)
+               goto out;
+
+       /* Change the clock frequency. */
+       clock = ios->clock;
+       if (clock > 52000000)
+               clock = 52000000;
+       slot->clock = clock;
+       clk_period = (host->sys_freq + clock - 1) / (2 * clock);
+
+       emm_switch.val = 0;
+       emm_switch.s.hs_timing = (ios->timing == MMC_TIMING_MMC_HS);
+       emm_switch.s.bus_width = bus_width;
+       emm_switch.s.power_class = power_class;
+       emm_switch.s.clk_hi = clk_period;
+       emm_switch.s.clk_lo = clk_period;
+       emm_switch.s.bus_id = slot->bus_id;
+
+       if (!switch_val_changed(slot, emm_switch.val))
+               goto out;
+
+       set_wdog(slot, 0);
+       do_switch(host, emm_switch.val);
+       slot->cached_switch = emm_switch.val;
+out:
+       host->release_bus(host);
+}
+
+const struct mmc_host_ops cvm_mmc_ops = {
+       .request        = cvm_mmc_request,
+       .set_ios        = cvm_mmc_set_ios,
+       .get_ro         = mmc_gpio_get_ro,
+       .get_cd         = mmc_gpio_get_cd,
+};
+
+static void cvm_mmc_set_clock(struct cvm_mmc_slot *slot, unsigned int clock)
+{
+       struct mmc_host *mmc = slot->mmc;
+
+       clock = min(clock, mmc->f_max);
+       clock = max(clock, mmc->f_min);
+       slot->clock = clock;
+}
+
+static int cvm_mmc_init_lowlevel(struct cvm_mmc_slot *slot)
+{
+       struct cvm_mmc_host *host = slot->host;
+       union mio_emm_switch emm_switch;
+
+       /* Enable this bus slot. */
+       host->emm_cfg |= (1ull << slot->bus_id);
+       writeq(host->emm_cfg, slot->host->base + MIO_EMM_CFG);
+       udelay(10);
+
+       /* Program initial clock speed and power. */
+       cvm_mmc_set_clock(slot, slot->mmc->f_min);
+       emm_switch.val = 0;
+       emm_switch.s.power_class = 10;
+       emm_switch.s.clk_hi = (slot->sclock / slot->clock) / 2;
+       emm_switch.s.clk_lo = (slot->sclock / slot->clock) / 2;
+
+       /* Make the changes take effect on this bus slot. */
+       emm_switch.s.bus_id = slot->bus_id;
+       do_switch(host, emm_switch.val);
+
+       slot->cached_switch = emm_switch.val;
+
+       /*
+        * Set watchdog timeout value and default reset value
+        * for the mask register. Finally, set the CARD_RCA
+        * bit so that we can get the card address relative
+        * to the CMD register for CMD7 transactions.
+        */
+       set_wdog(slot, 0);
+       writeq(0xe4390080ull, host->base + MIO_EMM_STS_MASK);
+       writeq(1, host->base + MIO_EMM_RCA);
+       return 0;
+}
+
+static int set_bus_width(struct device *dev, struct cvm_mmc_slot *slot, u32 id)
+{
+       u32 bus_width;
+       int ret;
+
+       /*
+        * The "cavium,bus-max-width" property is DEPRECATED and should
+        * not be used. We handle it here to support older firmware.
+        * Going forward, the standard "bus-width" property is used
+        * instead of the Cavium-specific property.
+        */
+       if (!(slot->mmc->caps & (MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA))) {
+               /* Try legacy "cavium,bus-max-width" property. */
+               ret = of_property_read_u32(dev->of_node, "cavium,bus-max-width",
+                                          &bus_width);
+               if (ret) {
+                       /* No bus width specified, use default. */
+                       bus_width = 8;
+                       dev_info(dev, "Default width 8 used for slot %u\n", id);
+               }
+       } else {
+               /* Hosts capable of 8-bit transfers can also do 4 bits */
+               bus_width = (slot->mmc->caps & MMC_CAP_8_BIT_DATA) ? 8 : 4;
+       }
+
+       switch (bus_width) {
+       case 8:
+               slot->bus_width = (MMC_BUS_WIDTH_8 - 1);
+               slot->mmc->caps = MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA;
+               break;
+       case 4:
+               slot->bus_width = (MMC_BUS_WIDTH_4 - 1);
+               slot->mmc->caps = MMC_CAP_4_BIT_DATA;
+               break;
+       case 1:
+               slot->bus_width = MMC_BUS_WIDTH_1;
+               break;
+       default:
+               dev_err(dev, "Invalid bus width for slot %u\n", id);
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static void set_frequency(struct device *dev, struct mmc_host *mmc, u32 id)
+{
+       int ret;
+
+       /*
+        * The "spi-max-frequency" property is DEPRECATED and should
+        * not be used. We handle it here to support older firmware.
+        * Going forward, the standard "max-frequency" property is
+        * used instead of the Cavium-specific property.
+        */
+       if (mmc->f_max == 0) {
+               /* Try legacy "spi-max-frequency" property. */
+               ret = of_property_read_u32(dev->of_node, "spi-max-frequency",
+                                          &mmc->f_max);
+               if (ret) {
+                       /* No frequency properties found, use default. */
+                       mmc->f_max = 52000000;
+                       dev_info(dev, "Default %u frequency used for slot %u\n",
+                                mmc->f_max, id);
+               }
+       } else if (mmc->f_max > 52000000)
+               mmc->f_max = 52000000;
+
+       /* Set minimum frequency */
+       mmc->f_min = 400000;
+}
+
+int cvm_mmc_slot_probe(struct device *dev, struct cvm_mmc_host *host)
+{
+       struct device_node *node = dev->of_node;
+       u32 id, cmd_skew, dat_skew;
+       struct cvm_mmc_slot *slot;
+       struct mmc_host *mmc;
+       u64 clock_period;
+       int ret;
+
+       ret = of_property_read_u32(node, "reg", &id);
+       if (ret) {
+               dev_err(dev, "Missing or invalid reg property on %s\n",
+                       of_node_full_name(node));
+               return ret;
+       }
+
+       if (id >= CAVIUM_MAX_MMC || host->slot[id]) {
+               dev_err(dev, "Invalid reg property on %s\n",
+                       of_node_full_name(node));
+               return -EINVAL;
+       }
+
+       mmc = mmc_alloc_host(sizeof(struct cvm_mmc_slot), dev);
+       if (!mmc)
+               return -ENOMEM;
+
+       slot = mmc_priv(mmc);
+       slot->mmc = mmc;
+       slot->host = host;
+
+       ret = mmc_of_parse(mmc);
+       if (ret)
+               goto err;
+
+       ret = set_bus_width(dev, slot, id);
+       if (ret)
+               goto err;
+
+       set_frequency(dev, mmc, id);
+
+       /* Octeon-specific DT properties. */
+       ret = of_property_read_u32(node, "cavium,cmd-clk-skew", &cmd_skew);
+       if (ret)
+               cmd_skew = 0;
+       ret = of_property_read_u32(node, "cavium,dat-clk-skew", &dat_skew);
+       if (ret)
+               dat_skew = 0;
+
+       /*
+        * We only have a 3.3v supply, so we are calling this mostly
+        * to get a sane OCR mask for other parts of the MMC subsytem.
+        */
+       ret = mmc_of_parse_voltage(node, &mmc->ocr_avail);
+       if (ret == -EINVAL)
+               goto err;
+
+       /*
+        * We do not have a voltage regulator, just a single
+        * GPIO line to control power to all of the slots. It
+        * is registered in the platform code. We can, however,
+        * still set the POWER_OFF capability as long as the
+        * GPIO was registered correctly.
+        */
+       if (!IS_ERR(host->global_pwr_gpiod)) {
+               mmc->caps |= MMC_CAP_POWER_OFF_CARD;
+               dev_info(dev, "Got global power GPIO\n");
+       } else
+               dev_info(dev, "Did not get global power GPIO\n");
+
+       /* Set up host parameters */
+       mmc->ops = &cvm_mmc_ops;
+
+       mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED |
+                    MMC_CAP_ERASE | MMC_CAP_CMD23;
+
+       mmc->max_segs = 1;
+
+       /* DMA size field can address up to 8 MB */
+       mmc->max_seg_size = 8 * 1024 * 1024;
+       mmc->max_req_size = mmc->max_seg_size;
+       /* External DMA is in 512 byte blocks */
+       mmc->max_blk_size = 512;
+       /* DMA block count field is 15 bits */
+       mmc->max_blk_count = 32767;
+
+       slot->clock = mmc->f_min;
+       slot->sclock = host->sys_freq;
+
+       /* Period in picoseconds. */
+       clock_period = 1000000000000ull / slot->sclock;
+       slot->cmd_cnt = (cmd_skew + clock_period / 2) / clock_period;
+       slot->dat_cnt = (dat_skew + clock_period / 2) / clock_period;
+
+       slot->bus_id = id;
+       slot->cached_rca = 1;
+
+       host->acquire_bus(host);
+       host->slot[id] = slot;
+       cvm_mmc_switch_to(slot);
+       cvm_mmc_init_lowlevel(slot);
+       host->release_bus(host);
+
+       ret = mmc_add_host(mmc);
+       if (ret) {
+               dev_err(dev, "mmc_add_host() returned %d\n", ret);
+               goto err;
+       }
+
+       return 0;
+
+err:
+       slot->host->slot[id] = NULL;
+
+       gpiod_set_value_cansleep(host->global_pwr_gpiod, 0);
+
+       mmc_free_host(slot->mmc);
+       return ret;
+}
+
+int cvm_mmc_slot_remove(struct cvm_mmc_slot *slot)
+{
+       mmc_remove_host(slot->mmc);
+       slot->host->slot[slot->bus_id] = NULL;
+       gpiod_set_value_cansleep(slot->host->global_pwr_gpiod, 0);
+       mmc_free_host(slot->mmc);
+
+       return 0;
+}
diff --git a/drivers/mmc/host/cavium_mmc.h b/drivers/mmc/host/cavium_mmc.h
new file mode 100644
index 0000000..27fb02b
--- /dev/null
+++ b/drivers/mmc/host/cavium_mmc.h
@@ -0,0 +1,303 @@
+/*
+ * Driver for MMC and SSD cards for Cavium OCTEON and ThunderX SOCs.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012-2016 Cavium Inc.
+ */
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mmc/host.h>
+#include <linux/of.h>
+#include <linux/scatterlist.h>
+#include <linux/semaphore.h>
+
+#define CAVIUM_MAX_MMC         4
+
+struct cvm_mmc_host {
+       struct device *dev;
+       void __iomem *base;
+       void __iomem *dma_base;
+       u64 emm_cfg;
+       int last_slot;
+       struct clk *clk;
+       int sys_freq;
+
+       struct mmc_request *current_req;
+       struct sg_mapping_iter smi;
+       bool dma_active;
+
+       struct gpio_desc *global_pwr_gpiod;
+
+       struct cvm_mmc_slot *slot[CAVIUM_MAX_MMC];
+
+       void (*acquire_bus)(struct cvm_mmc_host *);
+       void (*release_bus)(struct cvm_mmc_host *);
+       void (*int_enable)(struct cvm_mmc_host *, u64);
+};
+
+struct cvm_mmc_slot {
+       struct mmc_host *mmc;           /* slot-level mmc_core object */
+       struct cvm_mmc_host *host;      /* common hw for all slots */
+
+       u64 clock;
+       unsigned int sclock;
+
+       u64 cached_switch;
+       u64 cached_rca;
+
+       unsigned int cmd_cnt;           /* sample delay */
+       unsigned int dat_cnt;           /* sample delay */
+
+       int bus_width;
+       int bus_id;
+};
+
+struct cvm_mmc_cr_type {
+       u8 ctype;
+       u8 rtype;
+};
+
+struct cvm_mmc_cr_mods {
+       u8 ctype_xor;
+       u8 rtype_xor;
+};
+
+/* Bitfield definitions */
+
+union mio_emm_cmd {
+       u64 val;
+       struct mio_emm_cmd_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :2;
+               u64 bus_id:2;
+               u64 cmd_val:1;
+               u64 :3;
+               u64 dbuf:1;
+               u64 offset:6;
+               u64 :6;
+               u64 ctype_xor:2;
+               u64 rtype_xor:3;
+               u64 cmd_idx:6;
+               u64 arg:32;
+#else
+               u64 arg:32;
+               u64 cmd_idx:6;
+               u64 rtype_xor:3;
+               u64 ctype_xor:2;
+               u64 :6;
+               u64 offset:6;
+               u64 dbuf:1;
+               u64 :3;
+               u64 cmd_val:1;
+               u64 bus_id:2;
+               u64 :2;
+#endif
+       } s;
+};
+
+union mio_emm_dma {
+       u64 val;
+       struct mio_emm_dma_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :2;
+               u64 bus_id:2;
+               u64 dma_val:1;
+               u64 sector:1;
+               u64 dat_null:1;
+               u64 thres:6;
+               u64 rel_wr:1;
+               u64 rw:1;
+               u64 multi:1;
+               u64 block_cnt:16;
+               u64 card_addr:32;
+#else
+               u64 card_addr:32;
+               u64 block_cnt:16;
+               u64 multi:1;
+               u64 rw:1;
+               u64 rel_wr:1;
+               u64 thres:6;
+               u64 dat_null:1;
+               u64 sector:1;
+               u64 dma_val:1;
+               u64 bus_id:2;
+               u64 :2;
+#endif
+       } s;
+};
+
+union mio_emm_dma_cfg {
+       u64 val;
+       struct mio_emm_dma_cfg_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 en:1;
+               u64 rw:1;
+               u64 clr:1;
+               u64 :1;
+               u64 swap32:1;
+               u64 swap16:1;
+               u64 swap8:1;
+               u64 endian:1;
+               u64 size:20;
+               u64 adr:36;
+#else
+               u64 adr:36;
+               u64 size:20;
+               u64 endian:1;
+               u64 swap8:1;
+               u64 swap16:1;
+               u64 swap32:1;
+               u64 :1;
+               u64 clr:1;
+               u64 rw:1;
+               u64 en:1;
+#endif
+       } s;
+};
+
+union mio_emm_int {
+       u64 val;
+       struct mio_emm_int_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :57;
+               u64 switch_err:1;
+               u64 switch_done:1;
+               u64 dma_err:1;
+               u64 cmd_err:1;
+               u64 dma_done:1;
+               u64 cmd_done:1;
+               u64 buf_done:1;
+#else
+               u64 buf_done:1;
+               u64 cmd_done:1;
+               u64 dma_done:1;
+               u64 cmd_err:1;
+               u64 dma_err:1;
+               u64 switch_done:1;
+               u64 switch_err:1;
+               u64 :57;
+#endif
+       } s;
+};
+
+union mio_emm_rsp_sts {
+       u64 val;
+       struct mio_emm_rsp_sts_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :2;
+               u64 bus_id:2;
+               u64 cmd_val:1;
+               u64 switch_val:1;
+               u64 dma_val:1;
+               u64 dma_pend:1;
+               u64 :27;
+               u64 dbuf_err:1;
+               u64 :4;
+               u64 dbuf:1;
+               u64 blk_timeout:1;
+               u64 blk_crc_err:1;
+               u64 rsp_busybit:1;
+               u64 stp_timeout:1;
+               u64 stp_crc_err:1;
+               u64 stp_bad_sts:1;
+               u64 stp_val:1;
+               u64 rsp_timeout:1;
+               u64 rsp_crc_err:1;
+               u64 rsp_bad_sts:1;
+               u64 rsp_val:1;
+               u64 rsp_type:3;
+               u64 cmd_type:2;
+               u64 cmd_idx:6;
+               u64 cmd_done:1;
+#else
+               u64 cmd_done:1;
+               u64 cmd_idx:6;
+               u64 cmd_type:2;
+               u64 rsp_type:3;
+               u64 rsp_val:1;
+               u64 rsp_bad_sts:1;
+               u64 rsp_crc_err:1;
+               u64 rsp_timeout:1;
+               u64 stp_val:1;
+               u64 stp_bad_sts:1;
+               u64 stp_crc_err:1;
+               u64 stp_timeout:1;
+               u64 rsp_busybit:1;
+               u64 blk_crc_err:1;
+               u64 blk_timeout:1;
+               u64 dbuf:1;
+               u64 :4;
+               u64 dbuf_err:1;
+               u64 :27;
+               u64 dma_pend:1;
+               u64 dma_val:1;
+               u64 switch_val:1;
+               u64 cmd_val:1;
+               u64 bus_id:2;
+               u64 :2;
+#endif
+       } s;
+};
+
+union mio_emm_sample {
+       u64 val;
+       struct mio_emm_sample_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :38;
+               u64 cmd_cnt:10;
+               u64 :6;
+               u64 dat_cnt:10;
+#else
+               u64 dat_cnt:10;
+               u64 :6;
+               u64 cmd_cnt:10;
+               u64 :38;
+#endif
+       } s;
+};
+
+union mio_emm_switch {
+       u64 val;
+       struct mio_emm_switch_s {
+#ifdef __BIG_ENDIAN_BITFIELD
+               u64 :2;
+               u64 bus_id:2;
+               u64 switch_exe:1;
+               u64 switch_err0:1;
+               u64 switch_err1:1;
+               u64 switch_err2:1;
+               u64 :7;
+               u64 hs_timing:1;
+               u64 :5;
+               u64 bus_width:3;
+               u64 :4;
+               u64 power_class:4;
+               u64 clk_hi:16;
+               u64 clk_lo:16;
+#else
+               u64 clk_lo:16;
+               u64 clk_hi:16;
+               u64 power_class:4;
+               u64 :4;
+               u64 bus_width:3;
+               u64 :5;
+               u64 hs_timing:1;
+               u64 :7;
+               u64 switch_err2:1;
+               u64 switch_err1:1;
+               u64 switch_err0:1;
+               u64 switch_exe:1;
+               u64 bus_id:2;
+               u64 :2;
+#endif
+       } s;
+};
+
+/* Protoypes */
+irqreturn_t cvm_mmc_interrupt(int irq, void *dev_id);
+int cvm_mmc_slot_probe(struct device *dev, struct cvm_mmc_host *host);
+int cvm_mmc_slot_remove(struct cvm_mmc_slot *slot);
+extern const struct mmc_host_ops cvm_mmc_ops;
-- 
2.9.0.rc0.21.g7777322

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