linux/drivers/mmc/host/renesas_sdhi_internal_dmac.c
Wolfram Sang 2a55c1eac7 mmc: renesas_sdhi: prevent overflow for max_req_size
max_req_size is calculated by 'max_blk_size * max_blk_count' in the TMIO
core. So, specifying U32_MAX as max_blk_count will overflow this
calculation. It will cause no harm in practice because the immense high
number will overflow into another immense high number. However, it is
not good coding practice, so calculate max_blk_count so that
max_req_size will fit into unsigned int on ARM32/64.

Thanks to the Renesas BSP team for the bug report!

Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-04-15 11:55:54 +02:00

366 lines
11 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)
/*
* 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 = 0x00000704,
},
};
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,
.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);
}
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 (!dma_map_sg(&host->pdev->dev, sg, host->sg_len,
mmc_get_dma_dir(data)))
goto force_pio;
/* This DMAC cannot handle if buffer is not 8-bytes alignment */
if (!IS_ALIGNED(sg_dma_address(sg), 8))
goto force_pio_with_unmap;
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:
dma_unmap_sg(&host->pdev->dev, sg, host->sg_len, mmc_get_dma_dir(data));
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 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);
if (dir == DMA_FROM_DEVICE)
clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags);
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)
{
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);
}
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 soc_whitelist[] = {
/* specific ones */
{ .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) },
/* generic ones */
{ .soc_id = "r8a774a1" },
{ .soc_id = "r8a774c0" },
{ .soc_id = "r8a77470" },
{ .soc_id = "r8a7795" },
{ .soc_id = "r8a7796" },
{ .soc_id = "r8a77965" },
{ .soc_id = "r8a77970" },
{ .soc_id = "r8a77980" },
{ .soc_id = "r8a77990" },
{ .soc_id = "r8a77995" },
{ /* sentinel */ }
};
static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev)
{
const struct soc_device_attribute *soc = soc_device_match(soc_whitelist);
struct device *dev = &pdev->dev;
if (!soc)
return -ENODEV;
global_flags |= (unsigned long)soc->data;
dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms), GFP_KERNEL);
if (!dev->dma_parms)
return -ENOMEM;
/* 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",
.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");