linux/drivers/mmc/host/renesas_sdhi_internal_dmac.c
Yoshihiro Shimoda 69e7d76afd mmc: renesas_internal_dmac: add pre_req and post_req support
Add pre_req and post_req support to improve performance.

Inspired by a patch in the BSP by Masaharu Hayakawa.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/1608114572-1892-3-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-02-01 11:54:43 +01:00

444 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* DMA support for Internal DMAC with SDHI SD/SDIO controller
*
* Copyright (C) 2016-19 Renesas Electronics Corporation
* Copyright (C) 2016-17 Horms Solutions, Simon Horman
* Copyright (C) 2018-19 Sang Engineering, Wolfram Sang
*/
#include <linux/bitops.h>
#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) /* "upstream" = for read commands */
#define DTRAN_MODE_BUS_WIDTH (BIT(5) | BIT(4))
#define DTRAN_MODE_ADDR_MODE BIT(0) /* 1 = Increment address, 0 = Fixed */
/* 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_MASK_CLEAR GENMASK_ULL(31, 0)
#define INFO1_DTRANEND1 BIT(17)
#define INFO1_DTRANEND0 BIT(16)
/* DM_CM_INFO2 and DM_CM_INFO2_MASK */
#define INFO2_MASK_CLEAR GENMASK_ULL(31, 0)
#define INFO2_DTRANERR1 BIT(17)
#define INFO2_DTRANERR0 BIT(16)
enum renesas_sdhi_dma_cookie {
COOKIE_UNMAPPED,
COOKIE_PRE_MAPPED,
COOKIE_MAPPED,
};
/*
* 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.
*/
static unsigned long global_flags;
/*
* Workaround for avoiding to use RX DMAC by multiple channels.
* On R-Car H3 ES1.* and M3-W ES1.0, when multiple SDHI channels use
* RX DMAC simultaneously, sometimes hundreds of bytes data are not
* stored into the system memory even if the DMAC interrupt happened.
* So, this driver then uses one RX DMAC channel only.
*/
#define SDHI_INTERNAL_DMAC_ONE_RX_ONLY 0
#define SDHI_INTERNAL_DMAC_RX_IN_USE 1
/* RZ/A2 does not have the ADRR_MODE bit */
#define SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY 2
/* Definitions for sampling clocks */
static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = {
{
.clk_rate = 0,
.tap = 0x00000300,
.tap_hs400_4tap = 0x00000100,
},
};
static const struct renesas_sdhi_of_data of_rza2_compatible = {
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
TMIO_MMC_HAVE_CBSY,
.tmio_ocr_mask = MMC_VDD_32_33,
.capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_CMD23,
.bus_shift = 2,
.scc_offset = 0 - 0x1000,
.taps = rcar_gen3_scc_taps,
.taps_num = ARRAY_SIZE(rcar_gen3_scc_taps),
/* DMAC can handle 32bit blk count but only 1 segment */
.max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE,
.max_segs = 1,
};
static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = {
.tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2,
.capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
MMC_CAP_CMD23,
.capabilities2 = MMC_CAP2_NO_WRITE_PROTECT | MMC_CAP2_MERGE_CAPABLE,
.bus_shift = 2,
.scc_offset = 0x1000,
.taps = rcar_gen3_scc_taps,
.taps_num = ARRAY_SIZE(rcar_gen3_scc_taps),
/* DMAC can handle 32bit blk count but only 1 segment */
.max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE,
.max_segs = 1,
};
static const struct of_device_id renesas_sdhi_internal_dmac_of_match[] = {
{ .compatible = "renesas,sdhi-r7s9210", .data = &of_rza2_compatible, },
{ .compatible = "renesas,sdhi-mmc-r8a77470", .data = &of_rcar_gen3_compatible, },
{ .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, },
{ .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, },
{ .compatible = "renesas,rcar-gen3-sdhi", .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)
{
struct renesas_sdhi *priv = host_to_priv(host);
if (!host->chan_tx || !host->chan_rx)
return;
if (!enable)
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1,
INFO1_CLEAR);
if (priv->dma_priv.enable)
priv->dma_priv.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);
clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags);
renesas_sdhi_internal_dmac_enable_dma(host, true);
}
static void
renesas_sdhi_internal_dmac_dataend_dma(struct tmio_mmc_host *host) {
struct renesas_sdhi *priv = host_to_priv(host);
tasklet_schedule(&priv->dma_priv.dma_complete);
}
/*
* renesas_sdhi_internal_dmac_map() will be called with two difference
* sg pointers in two mmc_data by .pre_req(), but tmio host can have a single
* sg_ptr only. So, renesas_sdhi_internal_dmac_{un}map() should use a sg
* pointer in a mmc_data instead of host->sg_ptr.
*/
static void
renesas_sdhi_internal_dmac_unmap(struct tmio_mmc_host *host,
struct mmc_data *data,
enum renesas_sdhi_dma_cookie cookie)
{
bool unmap = cookie == COOKIE_UNMAPPED ? (data->host_cookie != cookie) :
(data->host_cookie == cookie);
if (unmap) {
dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len,
mmc_get_dma_dir(data));
data->host_cookie = COOKIE_UNMAPPED;
}
}
static bool
renesas_sdhi_internal_dmac_map(struct tmio_mmc_host *host,
struct mmc_data *data,
enum renesas_sdhi_dma_cookie cookie)
{
if (data->host_cookie == COOKIE_PRE_MAPPED)
return true;
if (!dma_map_sg(&host->pdev->dev, data->sg, data->sg_len,
mmc_get_dma_dir(data)))
return false;
data->host_cookie = cookie;
/* This DMAC cannot handle if buffer is not 128-bytes alignment */
if (!IS_ALIGNED(sg_dma_address(data->sg), 128)) {
renesas_sdhi_internal_dmac_unmap(host, data, cookie);
return false;
}
return true;
}
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_WIDTH;
if (!test_bit(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY, &global_flags))
dtran_mode |= DTRAN_MODE_ADDR_MODE;
if (!renesas_sdhi_internal_dmac_map(host, data, COOKIE_MAPPED))
goto force_pio;
if (data->flags & MMC_DATA_READ) {
dtran_mode |= DTRAN_MODE_CH_NUM_CH1;
if (test_bit(SDHI_INTERNAL_DMAC_ONE_RX_ONLY, &global_flags) &&
test_and_set_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags))
goto force_pio_with_unmap;
} else {
dtran_mode |= DTRAN_MODE_CH_NUM_CH0;
}
renesas_sdhi_internal_dmac_enable_dma(host, true);
/* 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(sg));
host->dma_on = true;
return;
force_pio_with_unmap:
renesas_sdhi_internal_dmac_unmap(host, data, COOKIE_UNMAPPED);
force_pio:
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 bool renesas_sdhi_internal_dmac_complete(struct tmio_mmc_host *host)
{
enum dma_data_direction dir;
if (!host->dma_on)
return false;
if (!host->data)
return false;
if (host->data->flags & MMC_DATA_READ)
dir = DMA_FROM_DEVICE;
else
dir = DMA_TO_DEVICE;
renesas_sdhi_internal_dmac_enable_dma(host, false);
renesas_sdhi_internal_dmac_unmap(host, host->data, COOKIE_MAPPED);
if (dir == DMA_FROM_DEVICE)
clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags);
host->dma_on = false;
return true;
}
static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg)
{
struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg;
spin_lock_irq(&host->lock);
if (!renesas_sdhi_internal_dmac_complete(host))
goto out;
tmio_mmc_do_data_irq(host);
out:
spin_unlock_irq(&host->lock);
}
static void renesas_sdhi_internal_dmac_end_dma(struct tmio_mmc_host *host)
{
if (host->data)
renesas_sdhi_internal_dmac_complete(host);
}
static void renesas_sdhi_internal_dmac_post_req(struct mmc_host *mmc,
struct mmc_request *mrq,
int err)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
struct mmc_data *data = mrq->data;
if (!data)
return;
renesas_sdhi_internal_dmac_unmap(host, data, COOKIE_UNMAPPED);
}
static void renesas_sdhi_internal_dmac_pre_req(struct mmc_host *mmc,
struct mmc_request *mrq)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
struct mmc_data *data = mrq->data;
if (!data)
return;
data->host_cookie = COOKIE_UNMAPPED;
renesas_sdhi_internal_dmac_map(host, data, COOKIE_PRE_MAPPED);
}
static void
renesas_sdhi_internal_dmac_request_dma(struct tmio_mmc_host *host,
struct tmio_mmc_data *pdata)
{
struct renesas_sdhi *priv = host_to_priv(host);
/* Disable DMAC interrupts, we don't use them */
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1_MASK,
INFO1_MASK_CLEAR);
renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO2_MASK,
INFO2_MASK_CLEAR);
/* Each value is set to non-zero to assume "enabling" each DMA */
host->chan_rx = host->chan_tx = (void *)0xdeadbeaf;
tasklet_init(&priv->dma_priv.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);
/* Add pre_req and post_req */
host->ops.pre_req = renesas_sdhi_internal_dmac_pre_req;
host->ops.post_req = renesas_sdhi_internal_dmac_post_req;
}
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,
.end = renesas_sdhi_internal_dmac_end_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 soc_dma_quirks[] = {
{ .soc_id = "r7s9210",
.data = (void *)BIT(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY) },
{ .soc_id = "r8a7795", .revision = "ES1.*",
.data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) },
{ .soc_id = "r8a7796", .revision = "ES1.0",
.data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) },
{ /* sentinel */ }
};
static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev)
{
const struct soc_device_attribute *soc = soc_device_match(soc_dma_quirks);
struct device *dev = &pdev->dev;
if (soc)
global_flags |= (unsigned long)soc->data;
/* value is max of SD_SECCNT. Confirmed by HW engineers */
dma_set_max_seg_size(dev, 0xffffffff);
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",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.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");