Re: [PATCH v5 2/2] mmc: sdhci-of-dwcmshc: Implement SDHCI CQE support
From: Adrian Hunter
Date: Mon Mar 04 2024 - 10:17:32 EST
On 4/03/24 16:30, Sergey Khimich wrote:
> Hello Adrian!
>
> Sorry for the late reply. Thanks for the comments - I`ll fix the next patch set version.
>
> On 03.01.2024 21:52, Adrian Hunter wrote:
>> On 31/12/23 16:46, Sergey Khimich wrote:
>>> From: Sergey Khimich <serghox@xxxxxxxxx>
>>>
>>> For enabling CQE support just set 'supports-cqe' in your DevTree file
>>> for appropriate mmc node.
>>>
>>> Signed-off-by: Sergey Khimich <serghox@xxxxxxxxx>
>>> ---
>>> drivers/mmc/host/Kconfig | 1 +
>>> drivers/mmc/host/sdhci-of-dwcmshc.c | 181 +++++++++++++++++++++++++++-
>>> 2 files changed, 180 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
>>> index 58bd5fe4cd25..f7594705b013 100644
>>> --- a/drivers/mmc/host/Kconfig
>>> +++ b/drivers/mmc/host/Kconfig
>>> @@ -233,6 +233,7 @@ config MMC_SDHCI_OF_DWCMSHC
>>> depends on MMC_SDHCI_PLTFM
>>> depends on OF
>>> depends on COMMON_CLK
>>> + select MMC_CQHCI
>>> help
>>> This selects Synopsys DesignWare Cores Mobile Storage Controller
>>> support.
>>> diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
>>> index 3a3bae6948a8..0ba1df4bcf36 100644
>>> --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
>>> +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
>>> @@ -20,6 +20,7 @@
>>> #include <linux/sizes.h>
>>> #include "sdhci-pltfm.h"
>>> +#include "cqhci.h"
>>> #define SDHCI_DWCMSHC_ARG2_STUFF GENMASK(31, 16)
>>> @@ -36,6 +37,9 @@
>>> #define DWCMSHC_ENHANCED_STROBE BIT(8)
>>> #define DWCMSHC_EMMC_ATCTRL 0x40
>>> +/* DWC IP vendor area 2 pointer */
>>> +#define DWCMSHC_P_VENDOR_AREA2 0xea
>>> +
>>> /* Rockchip specific Registers */
>>> #define DWCMSHC_EMMC_DLL_CTRL 0x800
>>> #define DWCMSHC_EMMC_DLL_RXCLK 0x804
>>> @@ -75,6 +79,11 @@
>>> #define BOUNDARY_OK(addr, len) \
>>> ((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
>>> +#define DWCMSHC_SDHCI_CQE_TRNS_MODE (SDHCI_TRNS_MULTI | \
>>> + SDHCI_TRNS_BLK_CNT_EN | \
>>> + SDHCI_TRNS_DMA)
>>> +
>>> +
>>> enum dwcmshc_rk_type {
>>> DWCMSHC_RK3568,
>>> DWCMSHC_RK3588,
>>> @@ -90,7 +99,9 @@ struct rk35xx_priv {
>>> struct dwcmshc_priv {
>>> struct clk *bus_clk;
>>> - int vendor_specific_area1; /* P_VENDOR_SPECIFIC_AREA reg */
>>> + int vendor_specific_area1; /* P_VENDOR_SPECIFIC_AREA1 reg */
>>> + int vendor_specific_area2; /* P_VENDOR_SPECIFIC_AREA2 reg */
>>> +
>>> void *priv; /* pointer to SoC private stuff */
>>> };
>>> @@ -210,6 +221,90 @@ static void dwcmshc_hs400_enhanced_strobe(struct mmc_host *mmc,
>>> sdhci_writel(host, vendor, reg);
>>> }
>>> +static int dwcmshc_execute_tuning(struct mmc_host *mmc, u32 opcode)
>>> +{
>>> + int err = sdhci_execute_tuning(mmc, opcode);
>>> + struct sdhci_host *host = mmc_priv(mmc);
>>> +
>>> + if (err)
>>> + return err;
>>> +
>>> + /*
>>> + * Tuning can leave the IP in an active state (Buffer Read Enable bit
>>> + * set) which prevents the entry to low power states (i.e. S0i3). Data
>>> + * reset will clear it.
>>> + */
>>> + sdhci_reset(host, SDHCI_RESET_DATA);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static u32 dwcmshc_cqe_irq_handler(struct sdhci_host *host, u32 intmask)
>>> +{
>>> + int cmd_error = 0;
>>> + int data_error = 0;
>>> +
>>> + if (!sdhci_cqe_irq(host, intmask, &cmd_error, &data_error))
>>> + return intmask;
>>> +
>>> + cqhci_irq(host->mmc, intmask, cmd_error, data_error);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static void dwcmshc_sdhci_cqe_enable(struct mmc_host *mmc)
>>> +{
>>> + struct sdhci_host *host = mmc_priv(mmc);
>>> + u8 ctrl;
>>> +
>>> + sdhci_writew(host, DWCMSHC_SDHCI_CQE_TRNS_MODE, SDHCI_TRANSFER_MODE);
>>> +
>>> + sdhci_cqe_enable(mmc);
>>> +
>>> + /*
>>> + * The "DesignWare Cores Mobile Storage Host Controller
>>> + * DWC_mshc / DWC_mshc_lite Databook" says:
>>> + * when Host Version 4 Enable" is 1 in Host Control 2 register,
>>> + * SDHCI_CTRL_ADMA32 bit means ADMA2 is selected.
>>> + * Selection of 32-bit/64-bit System Addressing:
>>> + * either 32-bit or 64-bit system addressing is selected by
>>> + * 64-bit Addressing bit in Host Control 2 register.
>>> + *
>>> + * On the other hand the "DesignWare Cores Mobile Storage Host
>>> + * Controller DWC_mshc / DWC_mshc_lite User Guide" says, that we have to
>>> + * set DMA_SEL to ADMA2 _only_ mode in the Host Control 2 register.
>>> + */
>>> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
>>> + ctrl &= ~SDHCI_CTRL_DMA_MASK;
>>> + ctrl |= SDHCI_CTRL_ADMA32;
>>> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
>>> +}
>>> +
>>> +static void dwcmshc_set_tran_desc(struct cqhci_host *cq_host, u8 **desc,
>>> + dma_addr_t addr, int len, bool end, bool dma64)
>>> +{
>>> + int tmplen, offset;
>>> +
>>> + if (likely(!len || BOUNDARY_OK(addr, len))) {
>>> + cqhci_set_tran_desc(*desc, addr, len, end, dma64);
>>> + return;
>>> + }
>>> +
>>> + offset = addr & (SZ_128M - 1);
>>> + tmplen = SZ_128M - offset;
>>> + cqhci_set_tran_desc(*desc, addr, tmplen, false, dma64);
>>> +
>>> + addr += tmplen;
>>> + len -= tmplen;
>>> + *desc += cq_host->trans_desc_len;
>>> + cqhci_set_tran_desc(*desc, addr, len, end, dma64);
>>> +}
>>> +
>>> +static void dwcmshc_cqhci_dumpregs(struct mmc_host *mmc)
>>> +{
>>> + sdhci_dumpregs(mmc_priv(mmc));
>>> +}
>>> +
>>> static void dwcmshc_rk3568_set_clock(struct sdhci_host *host, unsigned int clock)
>>> {
>>> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>> @@ -345,6 +440,7 @@ static const struct sdhci_ops sdhci_dwcmshc_ops = {
>>> .get_max_clock = dwcmshc_get_max_clock,
>>> .reset = sdhci_reset,
>>> .adma_write_desc = dwcmshc_adma_write_desc,
>>> + .irq = dwcmshc_cqe_irq_handler,
>>> };
>>> static const struct sdhci_ops sdhci_dwcmshc_rk35xx_ops = {
>>> @@ -379,6 +475,71 @@ static const struct sdhci_pltfm_data sdhci_dwcmshc_rk35xx_pdata = {
>>> SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
>>> };
>>> +static const struct cqhci_host_ops dwcmshc_cqhci_ops = {
>>> + .enable = dwcmshc_sdhci_cqe_enable,
>>> + .disable = sdhci_cqe_disable,
>>> + .dumpregs = dwcmshc_cqhci_dumpregs,
>>> + .set_tran_desc = dwcmshc_set_tran_desc,
>>> +};
>>> +
>>> +static void dwcmshc_cqhci_init(struct sdhci_host *host, struct platform_device *pdev)
>>> +{
>>> + struct cqhci_host *cq_host;
>>> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>> + struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
>>> + bool dma64 = false;
>>> + u16 clk;
>>> + int err;
>>> +
>>> + host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
>>> + cq_host = devm_kzalloc(&pdev->dev, sizeof(*cq_host), GFP_KERNEL);
>>> + if (!cq_host) {
>>> + dev_err(mmc_dev(host->mmc), "Unable to setup CQE: not enough memory\n");
>>> + return;
>>> + }
>>> +
>>> + /*
>>> + * For dwcmshc host controller we have to enable internal clock
>>> + * before access to some registers from Vendor Specific Aria 2.
>> Aria -> Area
>>
>>> + */
>>> + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>> + clk |= SDHCI_CLOCK_INT_EN;
>>> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>> + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>> + if (!(clk & SDHCI_CLOCK_INT_EN)) {
>>> + dev_err(mmc_dev(host->mmc), "Unable to setup CQE: internal clock enable error\n");
>>> + goto free_cq_host;
>>> + }
>>> +
>>> + cq_host->mmio = host->ioaddr + priv->vendor_specific_area2;
>>> + cq_host->ops = &dwcmshc_cqhci_ops;
>>> +
>>> + /* Enable using of 128-bit task descriptors */
>>> + dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
>>> + if (dma64) {
>>> + dev_dbg(mmc_dev(host->mmc), "128-bit task descriptors\n");
>>> + cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
>>> + }
>>> + err = cqhci_init(cq_host, host->mmc, dma64);
>>> + if (err) {
>>> + dev_err(mmc_dev(host->mmc), "Unable to setup CQE: error %d\n", err);
>>> + goto int_clock_disable;
>>> + }
>>> +
>>> + dev_dbg(mmc_dev(host->mmc), "CQE init done\n");
>>> +
>>> + return;
>>> +
>>> +int_clock_disable:
>>> + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
>>> + clk &= ~SDHCI_CLOCK_INT_EN;
>>> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
>>> +
>>> +free_cq_host:
>>> + devm_kfree(&pdev->dev, cq_host);
>>> +}
>>> +
>>> +
>>> static int dwcmshc_rk35xx_init(struct sdhci_host *host, struct dwcmshc_priv *dwc_priv)
>>> {
>>> int err;
>>> @@ -471,7 +632,7 @@ static int dwcmshc_probe(struct platform_device *pdev)
>>> struct rk35xx_priv *rk_priv = NULL;
>>> const struct sdhci_pltfm_data *pltfm_data;
>>> int err;
>>> - u32 extra;
>>> + u32 extra, caps;
>>> pltfm_data = device_get_match_data(&pdev->dev);
>>> if (!pltfm_data) {
>>> @@ -519,9 +680,12 @@ static int dwcmshc_probe(struct platform_device *pdev)
>>> priv->vendor_specific_area1 =
>>> sdhci_readl(host, DWCMSHC_P_VENDOR_AREA1) & DWCMSHC_AREA1_MASK;
>>> + priv->vendor_specific_area2 =
>>> + sdhci_readw(host, DWCMSHC_P_VENDOR_AREA2);
>> Is this OK for all IPs? ie. do they all have DWCMSHC_P_VENDOR_AREA2 register?
> Good question. Actually I can't guarantee that all dwcmshc-like IPs have DWCMSHC_P_VENDOR_AREA2 register,
> because I`ve tested my patch only on my pre-selicon FPGA prototype.
> But on the other hand according to the documentation I have, CQE-related registers are placed within this
> vendor2 block register. And thanks to Shawn Lin we know, Rockchip SoCs with this IP also have this reg.
> As I understand CQE for dwcmshc-like IPs will not work without DWCMSHC_P_VENDOR_AREA2.
Maybe it should be read only in that case? For example, after:
if (device_property_read_bool(&pdev->dev, "supports-cqe")) {