Merge tag 'mmc-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc

Pull MMC updates from Ulf Hansson:
 "MMC core:
   - Let the dma map ops deal with bouncing and drop dma_max_pfn() from
     the dma-mapping interface for ARM
   - Convert the generic MMC DT doc to YAML schemas
   - Drop questionable support for powered-on re-init of SDIO cards at
     runtime resume and for SDIO HW reset
   - Prevent questionable re-init of powered-on removable SDIO cards at
     system resume
   - Cleanup and clarify some SDIO core code

  MMC host:
   - tmio: Make runtime PM enablement more flexible for variants
   - tmio/renesas_sdhi: Rename DT doc tmio_mmc.txt to renesas,sdhi.txt
     to clarify
   - sdhci-pci: Add support for Intel EHL
   - sdhci-pci-o2micro: Enable support for 8-bit bus
   - sdhci-msm: Prevent acquiring a mutex while holding a spin_lock
   - sdhci-of-esdhc: Improve clock management and tuning
   - sdhci_am654: Enable support for 4 and 8-bit bus on J721E
   - sdhci-sprd: Use pinctrl for a proper signal voltage switch
   - sdhci-sprd: Add support for HS400 enhanced strobe mode
   - sdhci-sprd: Enable PHY DLL and allow delay config to stabilize the
     clock
   - sdhci-sprd: Add support for optional gate clock
   - sunxi-mmc: Convert DT doc to YAML schemas
   - meson-gx: Add support for broken DRAM access for DMA

  MEMSTICK core:
   - Fixup error path of memstick_init()"

* tag 'mmc-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (52 commits)
  mmc: sdhci_am654: Add dependency on MMC_SDHCI_AM654
  mmc: alcor: remove a redundant greater or equal to zero comparison
  mmc: sdhci-msm: fix mutex while in spinlock
  mmc: sdhci_am654: Make some symbols static
  dma-mapping: remove dma_max_pfn
  mmc: core: let the dma map ops handle bouncing
  dt-binding: mmc: rename tmio_mmc.txt to renesas,sdhi.txt
  mmc: sdhci-sprd: Add pin control support for voltage switch
  dt-bindings: mmc: sprd: Add pinctrl support
  mmc: sdhci-sprd: Add start_signal_voltage_switch ops
  mmc: sdhci-pci: Add support for Intel EHL
  mmc: tmio: Use dma_max_mapping_size() instead of a workaround
  mmc: sdio: Drop unused in-parameter from mmc_sdio_init_card()
  mmc: sdio: Drop unused in-parameter to mmc_sdio_reinit_card()
  mmc: sdio: Don't re-initialize powered-on removable SDIO cards at resume
  mmc: sdio: Drop powered-on re-init at runtime resume and HW reset
  mmc: sdio: Move comment about re-initialization to mmc_sdio_reinit_card()
  mmc: sdio: Drop mmc_claim|release_host() in mmc_sdio_power_restore()
  mmc: sdio: Turn sdio_run_irqs() into static
  mmc: sdhci: Fix indenting on SDHCI_CTRL_8BITBUS
  ...

1 files changed, 55 insertions, 15 deletions

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index fb842255de49..037311db3551 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -116,6 +116,9 @@
 #define SD_EMMC_TXD 0x94
 #define SD_EMMC_LAST_REG SD_EMMC_TXD
 
+#define SD_EMMC_SRAM_DATA_BUF_LEN 1536
+#define SD_EMMC_SRAM_DATA_BUF_OFF 0x200
+
 #define SD_EMMC_CFG_BLK_SIZE 512 /* internal buffer max: 512 bytes */
 #define SD_EMMC_CFG_RESP_TIMEOUT 256 /* in clock cycles */
 #define SD_EMMC_CMD_TIMEOUT 1024 /* in ms */
@@ -155,6 +158,8 @@ struct meson_host {
 	unsigned long req_rate;
 	bool ddr;
 
+	bool dram_access_quirk;
+
 	struct pinctrl *pinctrl;
 	struct pinctrl_state *pins_default;
 	struct pinctrl_state *pins_clk_gate;
@@ -219,12 +224,21 @@ static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
 static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
 					struct mmc_request *mrq)
 {
+	struct meson_host *host = mmc_priv(mmc);
 	struct mmc_data *data = mrq->data;
 	struct scatterlist *sg;
 	int i;
 	bool use_desc_chain_mode = true;
 
 	/*
+	 * When Controller DMA cannot directly access DDR memory, disable
+	 * support for Chain Mode to directly use the internal SRAM using
+	 * the bounce buffer mode.
+	 */
+	if (host->dram_access_quirk)
+		return;
+
+	/*
 	 * Broken SDIO with AP6255-based WiFi on Khadas VIM Pro has been
 	 * reported. For some strange reason this occurs in descriptor
 	 * chain mode only. So let's fall back to bounce buffer mode
@@ -1036,6 +1050,10 @@ static int meson_mmc_probe(struct platform_device *pdev)
 	host->dev = &pdev->dev;
 	dev_set_drvdata(&pdev->dev, host);
 
+	/* The G12A SDIO Controller needs an SRAM bounce buffer */
+	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
+					"amlogic,dram-access-quirk");
+
 	/* Get regulators and the supported OCR mask */
 	host->vqmmc_enabled = false;
 	ret = mmc_regulator_get_supply(mmc);
@@ -1133,9 +1151,16 @@ static int meson_mmc_probe(struct platform_device *pdev)
 		goto err_init_clk;
 
 	mmc->caps |= MMC_CAP_CMD23;
-	mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
+	if (host->dram_access_quirk) {
+		/* Limit to the available sram memory */
+		mmc->max_segs = SD_EMMC_SRAM_DATA_BUF_LEN / mmc->max_blk_size;
+		mmc->max_blk_count = mmc->max_segs;
+	} else {
+		mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
+		mmc->max_segs = SD_EMMC_DESC_BUF_LEN /
+				sizeof(struct sd_emmc_desc);
+	}
 	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
-	mmc->max_segs = SD_EMMC_DESC_BUF_LEN / sizeof(struct sd_emmc_desc);
 	mmc->max_seg_size = mmc->max_req_size;
 
 	/*
@@ -1145,15 +1170,27 @@ static int meson_mmc_probe(struct platform_device *pdev)
 	 */
 	mmc->caps2 &= ~MMC_CAP2_HS400;
 
-	/* data bounce buffer */
-	host->bounce_buf_size = mmc->max_req_size;
-	host->bounce_buf =
-		dma_alloc_coherent(host->dev, host->bounce_buf_size,
-				   &host->bounce_dma_addr, GFP_KERNEL);
-	if (host->bounce_buf == NULL) {
-		dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
-		ret = -ENOMEM;
-		goto err_free_irq;
+	if (host->dram_access_quirk) {
+		/*
+		 * The MMC Controller embeds 1,5KiB of internal SRAM
+		 * that can be used to be used as bounce buffer.
+		 * In the case of the G12A SDIO controller, use these
+		 * instead of the DDR memory
+		 */
+		host->bounce_buf_size = SD_EMMC_SRAM_DATA_BUF_LEN;
+		host->bounce_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF;
+		host->bounce_dma_addr = res->start + SD_EMMC_SRAM_DATA_BUF_OFF;
+	} else {
+		/* data bounce buffer */
+		host->bounce_buf_size = mmc->max_req_size;
+		host->bounce_buf =
+			dma_alloc_coherent(host->dev, host->bounce_buf_size,
+					   &host->bounce_dma_addr, GFP_KERNEL);
+		if (host->bounce_buf == NULL) {
+			dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
+			ret = -ENOMEM;
+			goto err_free_irq;
+		}
 	}
 
 	host->descs = dma_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
@@ -1170,8 +1207,9 @@ static int meson_mmc_probe(struct platform_device *pdev)
 	return 0;
 
 err_bounce_buf:
-	dma_free_coherent(host->dev, host->bounce_buf_size,
-			  host->bounce_buf, host->bounce_dma_addr);
+	if (!host->dram_access_quirk)
+		dma_free_coherent(host->dev, host->bounce_buf_size,
+				  host->bounce_buf, host->bounce_dma_addr);
 err_free_irq:
 	free_irq(host->irq, host);
 err_init_clk:
@@ -1195,8 +1233,10 @@ static int meson_mmc_remove(struct platform_device *pdev)
 
 	dma_free_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
 			  host->descs, host->descs_dma_addr);
-	dma_free_coherent(host->dev, host->bounce_buf_size,
-			  host->bounce_buf, host->bounce_dma_addr);
+
+	if (!host->dram_access_quirk)
+		dma_free_coherent(host->dev, host->bounce_buf_size,
+				  host->bounce_buf, host->bounce_dma_addr);
 
 	clk_disable_unprepare(host->mmc_clk);
 	clk_disable_unprepare(host->core_clk);