/*
* DMA support for Internal DMAC with SDHI SD/SDIO controller
*
* Copyright (C) 2016-17 Renesas Electronics Corporation
* Copyright (C) 2016-17 Horms Solutions, Simon Horman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/io-64-nonatomic-hi-lo.h>
#include <linux/mfd/tmio.h>
#include <linux/mmc/host.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <linux/sys_soc.h>
#include "renesas_sdhi.h"
#include "tmio_mmc.h"
#define DM_CM_DTRAN_MODE 0x820
#define DM_CM_DTRAN_CTRL 0x828
#define DM_CM_RST 0x830
#define DM_CM_INFO1 0x840
#define DM_CM_INFO1_MASK 0x848
#define DM_CM_INFO2 0x850
#define DM_CM_INFO2_MASK 0x858
#define DM_DTRAN_ADDR 0x880
/* DM_CM_DTRAN_MODE */
#define DTRAN_MODE_CH_NUM_CH0 0 /* "downstream" = for write commands */
#define DTRAN_MODE_CH_NUM_CH1 BIT(16) /* "uptream" = for read commands */
#define DTRAN_MODE_BUS_WID_TH (BIT(5) | BIT(4))
#define DTRAN_MODE_ADDR_MODE BIT(0) /* 1 = Increment address */
/* DM_CM_DTRAN_CTRL */
#define DTRAN_CTRL_DM_START BIT(0)
/* DM_CM_RST */
#define RST_DTRANRST1 BIT(9)
#define RST_DTRANRST0 BIT(8)
#define RST_RESERVED_BITS GENMASK_ULL(31, 0)
/* DM_CM_INFO1 and DM_CM_INFO1_MASK */
#define INFO1_CLEAR 0
#define INFO1_DTRANEND1 BIT(17)
#define INFO1_DTRANEND0 BIT(16)
/* DM_CM_INFO2 and DM_CM_INFO2_MASK */
#define INFO2_DTRANERR1 BIT(17)
#define INFO2_DTRANERR0 BIT(16)
/*
* Specification of this driver:
* - host->chan_{rx,tx} will be used as a flag of enabling/disabling the dma
* - Since this SDHI DMAC register set has 16 but 32-bit width, we
* need a custom accessor.
*/
/* Definitions for sampling clocks */
static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = {
{
.clk_rate = 0,
.tap = 0x00000300,
},
};
static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = {
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
TMIO_MMC_CLK_ACTUAL | TMIO_MMC_HAVE_CBSY |
TMIO_MMC_MIN_RCAR2,
.capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_CMD23,
.bus_shift = 2,
.scc_offset = 0x1000,
.taps = rcar_gen3_scc_taps,
.taps_num = ARRAY_SIZE(rcar_gen3_scc_taps),
/* Gen3 SDHI DMAC can handle 0xffffffff blk count, but seg = 1 */
.max_blk_count = 0xffffffff,
.max_segs = 1,
};
static const struct of_device_id renesas_sdhi_internal_dmac_of_match[] = {
{ .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, },
{ .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, },
{},
};
MODULE_DEVICE_TABLE(of, renesas_sdhi_internal_dmac_of_match);
static void
renesas_sdhi_internal_dmac_dm_write(struct tmio_mmc_host *host,
int addr, u64 val)
{
writeq(val, host->ctl + addr);
}
static void
renesas_sdhi_internal_dmac_enable_dma(struct tmio_mmc_host *host, bool enable)
{
if (!host->chan_tx || !host->chan_rx)
return;
if (!enable)
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1,
INFO1_CLEAR);
if (host->dma->enable)
host->dma->enable(host, enable);
}
static void
renesas_sdhi_internal_dmac_abort_dma(struct tmio_mmc_host *host) {
u64 val = RST_DTRANRST1 | RST_DTRANRST0;
renesas_sdhi_internal_dmac_enable_dma(host, false);
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST,
RST_RESERVED_BITS & ~val);
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST,
RST_RESERVED_BITS | val);
renesas_sdhi_internal_dmac_enable_dma(host, true);
}
static void
renesas_sdhi_internal_dmac_dataend_dma(struct tmio_mmc_host *host) {
tasklet_schedule(&host->dma_complete);
}
static void
renesas_sdhi_internal_dmac_start_dma(struct tmio_mmc_host *host,
struct mmc_data *data)
{
struct scatterlist *sg = host->sg_ptr;
u32 dtran_mode = DTRAN_MODE_BUS_WID_TH | DTRAN_MODE_ADDR_MODE;
enum dma_data_direction dir;
int ret;
u32 irq_mask;
/* This DMAC cannot handle if sg_len is not 1 */
WARN_ON(host->sg_len > 1);
/* This DMAC cannot handle if buffer is not 8-bytes alignment */
if (!IS_ALIGNED(sg->offset, 8))
goto force_pio;
if (data->flags & MMC_DATA_READ) {
dtran_mode |= DTRAN_MODE_CH_NUM_CH1;
dir = DMA_FROM_DEVICE;
irq_mask = TMIO_STAT_RXRDY;
} else {
dtran_mode |= DTRAN_MODE_CH_NUM_CH0;
dir = DMA_TO_DEVICE;
irq_mask = TMIO_STAT_TXRQ;
}
ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, dir);
if (ret == 0)
goto force_pio;
renesas_sdhi_internal_dmac_enable_dma(host, true);
/* disable PIO irqs to avoid "PIO IRQ in DMA mode!" */
tmio_mmc_disable_mmc_irqs(host, irq_mask);
/* set dma parameters */
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_MODE,
dtran_mode);
renesas_sdhi_internal_dmac_dm_write(host, DM_DTRAN_ADDR,
sg->dma_address);
return;
force_pio:
host->force_pio = true;
renesas_sdhi_internal_dmac_enable_dma(host, false);
}
static void renesas_sdhi_internal_dmac_issue_tasklet_fn(unsigned long arg)
{
struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
/* start the DMAC */
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_CTRL,
DTRAN_CTRL_DM_START);
}
static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg)
{
struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
enum dma_data_direction dir;
spin_lock_irq(&host->lock);
if (!host->data)
goto out;
if (host->data->flags & MMC_DATA_READ)
dir = DMA_FROM_DEVICE;
else
dir = DMA_TO_DEVICE;
renesas_sdhi_internal_dmac_enable_dma(host, false);
dma_unmap_sg(&host->pdev->dev, host->sg_ptr, host->sg_len, dir);
tmio_mmc_do_data_irq(host);
out:
spin_unlock_irq(&host->lock);
}
static void
renesas_sdhi_internal_dmac_request_dma(struct tmio_mmc_host *host,
struct tmio_mmc_data *pdata)
{
/* Each value is set to non-zero to assume "enabling" each DMA */
host->chan_rx = host->chan_tx = (void *)0xdeadbeaf;
tasklet_init(&host->dma_complete,
renesas_sdhi_internal_dmac_complete_tasklet_fn,
(unsigned long)host);
tasklet_init(&host->dma_issue,
renesas_sdhi_internal_dmac_issue_tasklet_fn,
(unsigned long)host);
}
static void
renesas_sdhi_internal_dmac_release_dma(struct tmio_mmc_host *host)
{
/* Each value is set to zero to assume "disabling" each DMA */
host->chan_rx = host->chan_tx = NULL;
}
static const struct tmio_mmc_dma_ops renesas_sdhi_internal_dmac_dma_ops = {
.start = renesas_sdhi_internal_dmac_start_dma,
.enable = renesas_sdhi_internal_dmac_enable_dma,
.request = renesas_sdhi_internal_dmac_request_dma,
.release = renesas_sdhi_internal_dmac_release_dma,
.abort = renesas_sdhi_internal_dmac_abort_dma,
.dataend = renesas_sdhi_internal_dmac_dataend_dma,
};
/*
* Whitelist of specific R-Car Gen3 SoC ES versions to use this DMAC
* implementation as others may use a different implementation.
*/
static const struct soc_device_attribute gen3_soc_whitelist[] = {
{ .soc_id = "r8a7795", .revision = "ES1.*" },
{ .soc_id = "r8a7795", .revision = "ES2.0" },
{ .soc_id = "r8a7796", .revision = "ES1.0" },
{ /* sentinel */ }
};
static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev)
{
if (!soc_device_match(gen3_soc_whitelist))
return -ENODEV;
return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops);
}
static const struct dev_pm_ops renesas_sdhi_internal_dmac_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
tmio_mmc_host_runtime_resume,
NULL)
};
static struct platform_driver renesas_internal_dmac_sdhi_driver = {
.driver = {
.name = "renesas_sdhi_internal_dmac",
.pm = &renesas_sdhi_internal_dmac_dev_pm_ops,
.of_match_table = renesas_sdhi_internal_dmac_of_match,
},
.probe = renesas_sdhi_internal_dmac_probe,
.remove = renesas_sdhi_remove,
};
module_platform_driver(renesas_internal_dmac_sdhi_driver);
MODULE_DESCRIPTION("Renesas SDHI driver for internal DMAC");
MODULE_AUTHOR("Yoshihiro Shimoda");
MODULE_LICENSE("GPL v2");