Re: [PATCH v6] mmc: dw_mmc: Add IDMAC 64-bit address mode support

From: Alim Akhtar
Date: Tue Oct 14 2014 - 08:12:41 EST

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In reply to: Prabu Thangamuthu: "[PATCH v6] mmc: dw_mmc: Add IDMAC 64-bit address mode support"
Next in thread: Vivek Gautam: "Re: [PATCH v6] mmc: dw_mmc: Add IDMAC 64-bit address mode support"
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Hi Prahu,
Thanks for a quick re-spin o the patch.
One last comment, this is more of a information seek.
On Thu, Oct 9, 2014 at 1:09 PM, Prabu Thangamuthu <Prabu.T@xxxxxxxxxxxx> wrote:
> Synopsys DW_MMC IP core supports Internal DMA Controller with 64-bit address mode from IP version 2.70a onwards.
> Updated the driver to support IDMAC 64-bit addressing mode.
>
> Tested the features in DW_MMC core v2.70a and v2.40a with HAPS-51 setup and driver is working fine.
>
> Signed-off-by: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
> ---
> Change log v6:
> - Updated with review comment.
>
> Change log v5:
> - Recreated the patch against linux-next as this patch is required for another patch http://www.spinics.net/lists/arm-kernel/msg357985.html
>
> Change log v4:
> - Add the dynamic support for 32-bit and 64-bit address mode based on hw configuration.
> - Removed the CONFIG_MMC_DW_IDMAC_64BIT_ADDRESS macro.
>
> drivers/mmc/host/dw_mmc.c | 195 +++++++++++++++++++++++++++++++++++---------
> drivers/mmc/host/dw_mmc.h | 11 +++
> include/linux/mmc/dw_mmc.h | 2 +
> 3 files changed, 170 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index 69f0cc6..c3b75a5 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -62,6 +62,24 @@
> SDMMC_IDMAC_INT_FBE | SDMMC_IDMAC_INT_RI | \
> SDMMC_IDMAC_INT_TI)
>
> +struct idmac_desc_64addr {
> + u32 des0; /* Control Descriptor */
> +
> + u32 des1; /* Reserved */
What is the default value of these _Reserved_ descriptors? As these
are pointers, do you thing initializing then to zero make sense?
> +
> + u32 des2; /*Buffer sizes */
> +#define IDMAC_64ADDR_SET_BUFFER1_SIZE(d, s) \
> + ((d)->des2 = ((d)->des2 & 0x03ffe000) | ((s) & 0x1fff))
> +
> + u32 des3; /* Reserved */
> +
> + u32 des4; /* Lower 32-bits of Buffer Address Pointer 1*/
> + u32 des5; /* Upper 32-bits of Buffer Address Pointer 1*/
> +
> + u32 des6; /* Lower 32-bits of Next Descriptor Address */
> + u32 des7; /* Upper 32-bits of Next Descriptor Address */
> +};
> +
> struct idmac_desc {
> u32 des0; /* Control Descriptor */
> #define IDMAC_DES0_DIC BIT(1)
> @@ -414,30 +432,66 @@ static void dw_mci_translate_sglist(struct dw_mci *host, struct mmc_data *data,
> unsigned int sg_len)
> {
> int i;
> - struct idmac_desc *desc = host->sg_cpu;
> + if (host->dma_64bit_address == 1) {
> + struct idmac_desc_64addr *desc = host->sg_cpu;
>
> - for (i = 0; i < sg_len; i++, desc++) {
> - unsigned int length = sg_dma_len(&data->sg[i]);
> - u32 mem_addr = sg_dma_address(&data->sg[i]);
> + for (i = 0; i < sg_len; i++, desc++) {
> + unsigned int length = sg_dma_len(&data->sg[i]);
> + u64 mem_addr = sg_dma_address(&data->sg[i]);
>
> - /* Set the OWN bit and disable interrupts for this descriptor */
> - desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC | IDMAC_DES0_CH;
> + /*
> + * Set the OWN bit and disable interrupts for this
> + * descriptor
> + */
> + desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC |
> + IDMAC_DES0_CH;
> + /* Buffer length */
> + IDMAC_64ADDR_SET_BUFFER1_SIZE(desc, length);
> +
> + /* Physical address to DMA to/from */
> + desc->des4 = mem_addr & 0xffffffff;
> + desc->des5 = mem_addr >> 32;
> + }
>
> - /* Buffer length */
> - IDMAC_SET_BUFFER1_SIZE(desc, length);
> + /* Set first descriptor */
> + desc = host->sg_cpu;
> + desc->des0 |= IDMAC_DES0_FD;
>
> - /* Physical address to DMA to/from */
> - desc->des2 = mem_addr;
> - }
> + /* Set last descriptor */
> + desc = host->sg_cpu + (i - 1) *
> + sizeof(struct idmac_desc_64addr);
> + desc->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
> + desc->des0 |= IDMAC_DES0_LD;
> +
> + } else {
> + struct idmac_desc *desc = host->sg_cpu;
> +
> + for (i = 0; i < sg_len; i++, desc++) {
> + unsigned int length = sg_dma_len(&data->sg[i]);
> + u32 mem_addr = sg_dma_address(&data->sg[i]);
> +
> + /*
> + * Set the OWN bit and disable interrupts for this
> + * descriptor
> + */
> + desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC |
> + IDMAC_DES0_CH;
> + /* Buffer length */
> + IDMAC_SET_BUFFER1_SIZE(desc, length);
> +
> + /* Physical address to DMA to/from */
> + desc->des2 = mem_addr;
> + }
>
> - /* Set first descriptor */
> - desc = host->sg_cpu;
> - desc->des0 |= IDMAC_DES0_FD;
> + /* Set first descriptor */
> + desc = host->sg_cpu;
> + desc->des0 |= IDMAC_DES0_FD;
>
> - /* Set last descriptor */
> - desc = host->sg_cpu + (i - 1) * sizeof(struct idmac_desc);
> - desc->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
> - desc->des0 |= IDMAC_DES0_LD;
> + /* Set last descriptor */
> + desc = host->sg_cpu + (i - 1) * sizeof(struct idmac_desc);
> + desc->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
> + desc->des0 |= IDMAC_DES0_LD;
> + }
>
> wmb();
> }
> @@ -466,29 +520,67 @@ static void dw_mci_idmac_start_dma(struct dw_mci *host, unsigned int sg_len)
>
> static int dw_mci_idmac_init(struct dw_mci *host)
> {
> - struct idmac_desc *p;
> int i;
>
> - /* Number of descriptors in the ring buffer */
> - host->ring_size = PAGE_SIZE / sizeof(struct idmac_desc);
> + if (host->dma_64bit_address == 1) {
> + struct idmac_desc_64addr *p;
> + /* Number of descriptors in the ring buffer */
> + host->ring_size = PAGE_SIZE / sizeof(struct idmac_desc_64addr);
> +
> + /* Forward link the descriptor list */
> + for (i = 0, p = host->sg_cpu; i < host->ring_size - 1;
> + i++, p++) {
> + p->des6 = (host->sg_dma +
> + (sizeof(struct idmac_desc_64addr) *
> + (i + 1))) & 0xffffffff;
> +
> + p->des7 = (host->sg_dma +
> + (sizeof(struct idmac_desc_64addr) *
> + (i + 1))) >> 32;
> + }
> +
> + /* Set the last descriptor as the end-of-ring descriptor */
> + p->des6 = host->sg_dma & 0xffffffff;
> + p->des7 = host->sg_dma >> 32;
> + p->des0 = IDMAC_DES0_ER;
> +
> + } else {
> + struct idmac_desc *p;
> + /* Number of descriptors in the ring buffer */
> + host->ring_size = PAGE_SIZE / sizeof(struct idmac_desc);
>
> - /* Forward link the descriptor list */
> - for (i = 0, p = host->sg_cpu; i < host->ring_size - 1; i++, p++)
> - p->des3 = host->sg_dma + (sizeof(struct idmac_desc) * (i + 1));
> + /* Forward link the descriptor list */
> + for (i = 0, p = host->sg_cpu; i < host->ring_size - 1; i++, p++)
> + p->des3 = host->sg_dma + (sizeof(struct idmac_desc) *
> + (i + 1));
>
> - /* Set the last descriptor as the end-of-ring descriptor */
> - p->des3 = host->sg_dma;
> - p->des0 = IDMAC_DES0_ER;
> + /* Set the last descriptor as the end-of-ring descriptor */
> + p->des3 = host->sg_dma;
> + p->des0 = IDMAC_DES0_ER;
> + }
>
> dw_mci_idmac_reset(host);
>
> - /* Mask out interrupts - get Tx & Rx complete only */
> - mci_writel(host, IDSTS, IDMAC_INT_CLR);
> - mci_writel(host, IDINTEN, SDMMC_IDMAC_INT_NI | SDMMC_IDMAC_INT_RI |
> - SDMMC_IDMAC_INT_TI);
> + if (host->dma_64bit_address == 1) {
> + /* Mask out interrupts - get Tx & Rx complete only */
> + mci_writel(host, IDSTS64, IDMAC_INT_CLR);
> + mci_writel(host, IDINTEN64, SDMMC_IDMAC_INT_NI |
> + SDMMC_IDMAC_INT_RI | SDMMC_IDMAC_INT_TI);
> +
> + /* Set the descriptor base address */
> + mci_writel(host, DBADDRL, host->sg_dma & 0xffffffff);
> + mci_writel(host, DBADDRU, host->sg_dma >> 32);
> +
> + } else {
> + /* Mask out interrupts - get Tx & Rx complete only */
> + mci_writel(host, IDSTS, IDMAC_INT_CLR);
> + mci_writel(host, IDINTEN, SDMMC_IDMAC_INT_NI |
> + SDMMC_IDMAC_INT_RI | SDMMC_IDMAC_INT_TI);
> +
> + /* Set the descriptor base address */
> + mci_writel(host, DBADDR, host->sg_dma);
> + }
>
> - /* Set the descriptor base address */
> - mci_writel(host, DBADDR, host->sg_dma);
> return 0;
> }
>
> @@ -2045,11 +2137,22 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
>
> #ifdef CONFIG_MMC_DW_IDMAC
> /* Handle DMA interrupts */
> - pending = mci_readl(host, IDSTS);
> - if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
> - mci_writel(host, IDSTS, SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI);
> - mci_writel(host, IDSTS, SDMMC_IDMAC_INT_NI);
> - host->dma_ops->complete(host);
> + if (host->dma_64bit_address == 1) {
> + pending = mci_readl(host, IDSTS64);
> + if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
> + mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_TI |
> + SDMMC_IDMAC_INT_RI);
> + mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_NI);
> + host->dma_ops->complete(host);
> + }
> + } else {
> + pending = mci_readl(host, IDSTS);
> + if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
> + mci_writel(host, IDSTS, SDMMC_IDMAC_INT_TI |
> + SDMMC_IDMAC_INT_RI);
> + mci_writel(host, IDSTS, SDMMC_IDMAC_INT_NI);
> + host->dma_ops->complete(host);
> + }
> }
> #endif
>
> @@ -2309,6 +2412,22 @@ static void dw_mci_cleanup_slot(struct dw_mci_slot *slot, unsigned int id)
>
> static void dw_mci_init_dma(struct dw_mci *host)
> {
> + int addr_config;
> + /* Check ADDR_CONFIG bit in HCON to find IDMAC address bus width */
> + addr_config = (mci_readl(host, HCON) >> 27) & 0x01;
> +
> + if (addr_config == 1) {
> + /* host supports IDMAC in 64-bit address mode */
> + host->dma_64bit_address = 1;
> + dev_info(host->dev, "IDMAC supports 64-bit address mode.\n");
> + if (!dma_set_mask(host->dev, DMA_BIT_MASK(64)))
> + dma_set_coherent_mask(host->dev, DMA_BIT_MASK(64));
> + } else {
> + /* host supports IDMAC in 32-bit address mode */
> + host->dma_64bit_address = 0;
> + dev_info(host->dev, "IDMAC supports 32-bit address mode.\n");
> + }
> +
> /* Alloc memory for sg translation */
> host->sg_cpu = dmam_alloc_coherent(host->dev, PAGE_SIZE,
> &host->sg_dma, GFP_KERNEL);
> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
> index 01b99e8..64b04aa 100644
> --- a/drivers/mmc/host/dw_mmc.h
> +++ b/drivers/mmc/host/dw_mmc.h
> @@ -55,6 +55,17 @@
> #define SDMMC_BUFADDR 0x098
> #define SDMMC_CDTHRCTL 0x100
> #define SDMMC_DATA(x) (x)
> +/*
> +* Registers to support idmac 64-bit address mode
> +*/
> +#define SDMMC_DBADDRL 0x088
> +#define SDMMC_DBADDRU 0x08c
> +#define SDMMC_IDSTS64 0x090
> +#define SDMMC_IDINTEN64 0x094
> +#define SDMMC_DSCADDRL 0x098
> +#define SDMMC_DSCADDRU 0x09c
> +#define SDMMC_BUFADDRL 0x0A0
> +#define SDMMC_BUFADDRU 0x0A4
>
> /*
> * Data offset is difference according to Version
> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
> index 0013669..9e6eabb 100644
> --- a/include/linux/mmc/dw_mmc.h
> +++ b/include/linux/mmc/dw_mmc.h
> @@ -54,6 +54,7 @@ struct mmc_data;
> * transfer is in progress.
> * @use_dma: Whether DMA channel is initialized or not.
> * @using_dma: Whether DMA is in use for the current transfer.
> + * @dma_64bit_address: Whether DMA supports 64-bit address mode or not.
> * @sg_dma: Bus address of DMA buffer.
> * @sg_cpu: Virtual address of DMA buffer.
> * @dma_ops: Pointer to platform-specific DMA callbacks.
> @@ -140,6 +141,7 @@ struct dw_mci {
> /* DMA interface members*/
> int use_dma;
> int using_dma;
> + int dma_64bit_address;
>
> dma_addr_t sg_dma;
> void *sg_cpu;
> --
> 1.7.6.5
>

--
Regards,
Alim
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Next message: Tanya Brokhman: "Re: [PATCH v3] mtd: ubi: Extend UBI layer debug/messaging capabilities"
Previous message: Mark Hounschell: "Re: [PATCH] staging: dgap: re-arrange functions for removing forward declarations."
In reply to: Prabu Thangamuthu: "[PATCH v6] mmc: dw_mmc: Add IDMAC 64-bit address mode support"
Next in thread: Vivek Gautam: "Re: [PATCH v6] mmc: dw_mmc: Add IDMAC 64-bit address mode support"
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