Hi Ludovic, Jaehoon Chung,
Thank you for your review comments,
On 04/26/2016 04:15 PM, Jaehoon Chung wrote:
>
> On 04/26/2016 05:58 PM, Ludovic Desroches wrote:
> > On Wed, Apr 20, 2016 at 12:22:59PM +0000, Prabu Thangamuthu wrote:
> >> Patch for Standard SD Host Controller Interface compliant Synopsys
> >> sdhci-dwc controller driver. This code supports PCI based interface.
> >>
> >> Signed-off-by: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
> >> ---
> >> Change log v3:
> >> -Removed unused code.
> >> -Updated review comments.
> >>
> >> Change log v2:
> >> -Removed Synopsys specific PCI device ID's from pci_ids.h.
> >> -Updated the PCI device ID's in sdhci-pci-core.c.
> >>
> >> MAINTAINERS | 7 +
> >> drivers/mmc/host/Makefile | 3 +-
> >> drivers/mmc/host/sdhci-pci-core.c | 14 ++
> >> drivers/mmc/host/sdhci-pci-dwc.c | 260
> >> ++++++++++++++++++++++++++++++++++++++
> >> drivers/mmc/host/sdhci-pci-dwc.h | 55 ++++++++
> >> 5 files changed, 338 insertions(+), 1 deletion(-) create mode
> >> 100644 drivers/mmc/host/sdhci-pci-dwc.c create mode 100644
> >> drivers/mmc/host/sdhci-pci-dwc.h
> >>
> >> diff --git a/MAINTAINERS b/MAINTAINERS index 1d5b4be..01b40da
> 100644
> >> --- a/MAINTAINERS
> >> +++ b/MAINTAINERS
> >> @@ -9751,6 +9751,13 @@ S: Maintained
> >> F: include/linux/mmc/dw_mmc.h
> >> F: drivers/mmc/host/dw_mmc*
> >>
> >> +SYNOPSYS SDHCI COMPLIANT DWC MSHC DRIVER
> >> +M: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
> >> +M: Manjunath M B <manjumb@xxxxxxxxxxxx>
> >> +L: linux-mmc@xxxxxxxxxxxxxxx
> >> +S: Maintained
> >> +F: drivers/mmc/host/sdhci-pci-dwc*
> >> +
> >> SYSTEM TRACE MODULE CLASS
> >> M: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> >> S: Maintained
> >> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> >> index af918d2..092a746 100644
> >> --- a/drivers/mmc/host/Makefile
> >> +++ b/drivers/mmc/host/Makefile
> >> @@ -9,7 +9,8 @@ obj-$(CONFIG_MMC_MXC) += mxcmmc.o
> >> obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
> >> obj-$(CONFIG_MMC_SDHCI) += sdhci.o
> >> obj-$(CONFIG_MMC_SDHCI_PCI) += sdhci-pci.o
> >> -sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o
> >> +sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o \
> >> + sdhci-pci-dwc.o
> >> obj-$(subst m,y,$(CONFIG_MMC_SDHCI_PCI)) += sdhci-pci-data.o
> >> obj-$(CONFIG_MMC_SDHCI_ACPI) += sdhci-acpi.o
> >> obj-$(CONFIG_MMC_SDHCI_PXAV3) += sdhci-pxav3.o
> >> diff --git a/drivers/mmc/host/sdhci-pci-core.c
> >> b/drivers/mmc/host/sdhci-pci-core.c
> >> index 79e1901..4a7769c 100644
> >> --- a/drivers/mmc/host/sdhci-pci-core.c
> >> +++ b/drivers/mmc/host/sdhci-pci-core.c
> >> @@ -31,6 +31,7 @@
> >> #include "sdhci.h"
> >> #include "sdhci-pci.h"
> >> #include "sdhci-pci-o2micro.h"
> >> +#include "sdhci-pci-dwc.h"
> >>
> >>
> /**********************************************************
> *******************\
> >> * *
> >> @@ -70,6 +71,11 @@ static int ricoh_mmc_resume(struct sdhci_pci_chip
> *chip)
> >> msleep(500);
> >> return 0;
> >> }
> >> +/* Synopsys SDHCI compliant Controller */ static const struct
> >> +sdhci_pci_fixes sdhci_snps = {
> >> + .probe_slot = sdhci_pci_probe_slot_snps,
> >> + .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
> >> +};
> >>
> >> static const struct sdhci_pci_fixes sdhci_ricoh = {
> >> .probe = ricoh_probe,
> >> @@ -797,6 +803,14 @@ static const struct sdhci_pci_fixes sdhci_amd =
> >> {
> >>
> >> static const struct pci_device_id pci_ids[] = {
> >> {
> >> + .vendor = PCI_VENDOR_ID_SYNOPSYS,
> >> + .device = 0xc201, /* Device ID of sdhci-dwc on
> Haps51 */
> >> + .subvendor = PCI_ANY_ID,
> >> + .subdevice = PCI_ANY_ID,
> >> + .driver_data = (kernel_ulong_t)&sdhci_snps,
> >> + },
> >> +
> >> + {
> >> .vendor = PCI_VENDOR_ID_RICOH,
> >> .device = PCI_DEVICE_ID_RICOH_R5C822,
> >> .subvendor = PCI_ANY_ID,
> >> diff --git a/drivers/mmc/host/sdhci-pci-dwc.c
> >> b/drivers/mmc/host/sdhci-pci-dwc.c
> >> new file mode 100644
> >> index 0000000..3490af8
> >> --- /dev/null
> >> +++ b/drivers/mmc/host/sdhci-pci-dwc.c
> >> @@ -0,0 +1,260 @@
> >> +/*
> >> + * Copyright (C) 2016 Synopsys, Inc.
> >> + *
> >> + * Author: Manjunath M B <manjumb@xxxxxxxxxxxx>
> >> + *
> >> + * This software is licensed under the terms of the GNU General
> >> +Public
> >> + * License version 2, as published by the Free Software Foundation,
> >> +and
> >> + * may be copied, distributed, and modified under those terms.
> >> + *
> >> + * This program is distributed in the hope that it will be useful,
> >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> >> + * GNU General Public License for more details.
> >> + *
> >> + */
> >> +
> >> +#include <linux/pci.h>
> >> +#include <linux/delay.h>
> >> +#include <linux/module.h>
> >> +#include <linux/moduleparam.h>
> >> +
> >> +#include "sdhci.h"
> >> +#include "sdhci-pci.h"
> >> +#include "sdhci-pci-dwc.h"
> >> +
> >>
> +/*********************************************************
> ********************\
> >> + * *
> >> + * Hardware specific clock handling *
> >> + * *
> >>
> +\*********************************************************
> ********************/
> >> +static const struct sdhci_ops *sdhci_ops; /* Low level hw interface */
> >> +
> >> +static void snps_reset_dcm(struct sdhci_host *host,
> >> + unsigned int mask, unsigned char reset)
>
> unsigned int/unsigned char -> u32/u8 ?
>
OK, We will update it accordingly.
>
> >> +{
> >> + u32 reg = 0;
> >> + u16 vendor_ptr = 0;
> >
> > These variables can't be used uninitialized so no need to initialize
> > them.
> >
OK, We will update it accordingly.
> >> +
> >> + vendor_ptr = sdhci_readw(host, SDHCI_UHS2_VENDOR);
> >> +
> >> + reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
> >> +
> >> + if (reset == 1)
> >> + reg |= mask;
> >> + else
> >> + reg &= ~mask;
> >> +
> >> + sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr)); }
> >> +
> >> +static void sdhci_set_clock_snps(struct sdhci_host *host,
> >> + unsigned int clock)
> >> +{
> >> + int div = 0;
> >> + int mul = 0;
> >> + int div_val = 0;
> >> + int mul_val = 0;
> >> + int mul_div_val = 0;
> >> + u32 reg = 0;
> >> + u16 clk = 0;
> >> + u16 vendor_ptr = 0;
> >> + u32 mask = 0;
> >> + unsigned long timeout;
> >> + u32 tx_clk_phase_val = SDHC_DEF_TX_CLK_PH_VAL;
> >> + u32 rx_clk_phase_val = SDHC_DEF_RX_CLK_PH_VAL;
> >> +
> >
> > Some variables don't need to be initialized here.
>
> tx/rx_clk_phase_val don't need?
> i didn't see any modifying these vales.
>
> And some variables don't need to define..can be reused.
>
OK, We will update it accordingly.
> >
> >> + /*
> >> + * if clock is less than 25MHz, divided clock is used.
> >> + * For divided clock, we can use the standard sdhci_set_clock().
> >> + * For clock above 25MHz, DRP clock is used
> >> + * Here, we cannot use sdhci_set_clock(), we need to program
> >> + * TX RX CLOCK DCM DRP for appropriate clock
> >> + */
> >> +
> >> + if (clock <= 25000000) {
> >> + /* Then call generic set_clock */
> >> + if (sdhci_ops->set_clock)
> >> + sdhci_ops->set_clock(host, clock);
> >
> > I am not sure about this part. You may simply call sdhci_set_clock()
> > instead of sdhci_ops->set_clock(). See my latest comment, it is not
> > clear what is behind set_clock().
> >
As we have built our own clocking logic using DCM, we want to use our
own set_clock function for the frequency above 25MHz.
For lower frequencies, our clocking module program is same as sdhci_set_clock().
So we are calling sdhci_ops->set_clock() which is same as sdhci_set_clock().
> >> + } else {
> >> +
> >> + host->mmc->actual_clock = 0;
> >> + vendor_ptr = sdhci_readw(host, SDHCI_UHS2_VENDOR);
> >> +
> >> + /* Select un-phase shifted clock before reset Tx Tuning
> DCM*/
> >> + reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
> >> + reg &= ~SDHC_TX_CLK_SEL_TUNED;
> >> + sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr));
> >> + mdelay(10);
> >> +
> >> + sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> >> +
> >> + /* Lets chose the Mulitplier value to be 0x2 */
> >> + mul = 0x2;
> >> + for (div = 1; div <= 32; div++) {
> >> + if (((host->max_clk * mul) / div)
> >> + <= clock)
> >> + break;
> >> + }
> >> + /*
> >> + * Set Programmable Clock Mode in the Clock
> >> + * Control register.
> >> + */
> >> + div_val = div - 1;
> >> + mul_val = mul - 1;
> >> +
> >> + host->mmc->actual_clock = (host->max_clk * mul) / div;
> >> + /*
> >> + * Program the DCM DRP
> >> + * Step 1: Assert DCM Reset
> >> + * Step 2: Program the mul and div values in DRP
> >> + * Step 3: Read from DRP base 0x00 to restore DCM output as
> per
> >> + *
> www.xilinx.com/support/documentation/user_guides/ug191.pdf
> >> + * Step 4: De-Assert reset to DCM
> >> + */
> >> +
> >> + mask = SDHC_CARD_TX_CLK_DCM_RST;
> >> + snps_reset_dcm(host, mask, 1);
> >> +
> >> + mul_div_val = (mul_val << 8) | div_val;
> >> + sdhci_writew(host, mul_div_val,
> TXRX_CLK_DCM_MUL_DIV_DRP);
> >> +
> >> + reg = sdhci_readl(host, TXRX_CLK_DCM_DRP_BASE_51);
> >> +
> >> + snps_reset_dcm(host, mask, 0);
> >> +
> >> + clk |= SDHCI_PROG_CLOCK_MODE | SDHCI_CLOCK_INT_EN;
> >> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> >> +
> >> + /* Wait max 20 ms */
> >> + timeout = 20;
> >> + while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
> >> + & SDHCI_CLOCK_INT_STABLE)) {
> >> + if (timeout == 0) {
> >> + pr_err("%s: Internal clock never stabilised\n",
> >> + mmc_hostname(host-
> >mmc));
> >> + return;
> >> + }
> >> + timeout--;
> >> + mdelay(1);
> >> + }
> >> +
> >> + clk |= SDHCI_CLOCK_CARD_EN;
> >> + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> >> +
> >> + /*
> >> + * This Clock might have affected the TX CLOCK DCM and RX
> CLOCK
> >> + * DCM which are used for Phase control; Reset these DCM's
> >> + * for proper clock output
> >> + *
> >> + * Step 1: Reset the DCM
> >> + * Step 2: De-Assert reset to DCM
> >> + */
> >> +
> >> + mask = SDHC_TUNING_TX_CLK_DCM_RST |
> SDHC_TUNING_RX_CLK_DCM_RST;
> >> + snps_reset_dcm(host, mask, 1);
> >> + mdelay(10);
> >> + snps_reset_dcm(host, mask, 0);
> >> +
> >> + /* Select working phase value if clock is <= 50MHz */
> >> + if (clock <= 50000000) {
> >> + /*Change the Tx Phase value here */
> >> + reg = sdhci_readl(host, (SDHC_GPIO_OUT +
> vendor_ptr));
> >> + reg |= (SDHC_TUNING_TX_CLK_SEL_MASK &
> >> + (tx_clk_phase_val <<
> SDHC_TUNING_TX_CLK_SEL_SHIFT));
> >> +
> >> + sdhci_writel(host, reg, (SDHC_GPIO_OUT +
> vendor_ptr));
> >> + mdelay(10);
> >> +
> >> + /* Program to select phase shifted clock */
> >> + reg |= SDHC_TX_CLK_SEL_TUNED;
> >> + sdhci_writel(host, reg, (SDHC_GPIO_OUT +
> vendor_ptr));
> >> +
> >> + /*
> >> + * For 50Mhz, tuning is not possible.
> >> + * Lets fix the sampling Phase of Rx Clock here.
> >> + */
> >> + reg = sdhci_readl(host, (SDHC_DBOUNCE +
> vendor_ptr));
> >> + reg &= ~SDHC_TUNING_RX_CLK_SEL_MASK;
> >> + reg |= (SDHC_TUNING_RX_CLK_SEL_MASK &
> >> + rx_clk_phase_val);
> >> + sdhci_writel(host, reg, (SDHC_DBOUNCE +
> vendor_ptr));
> >> + }
> >> + mdelay(10);
> >> + }
> >> +}
> >> +
> >> +static int snps_init_clock(struct sdhci_host *host) {
> >> + int div = 0;
> >> + int mul = 0;
> >> + int div_val = 0;
> >> + int mul_val = 0;
> >> + int mul_div_val = 0;
> >> + int reg = 0;
> >> + u32 mask = 0;
> >> +
> >
> > Some variables don't need initialization here or you can directly
> > assign the right value: int div = 2, mul = 2, etc.
>
> I think div/mul variables don't need to define, right?
> and mul_val and div_val also don't need.
>
> Finally, mul,div didn't need..just use mul_val and div_val are 1?
> It seems that mul_val and div_val are already fixed. (just 1)
>
> >
> >> + /* Configure the BCLK DRP to get 100 MHZ Clock */
>
> Combine with the below comment.
OK. We will update it accordingly.
>
> >> +
> >> + /*
> >> + * To get 100MHz from 100MHz input freq,
> >> + * mul=2 and div=2
> >> + * Formula: output_clock = (input clock * mul) / div
> >> + */
> >> + mul = 2;
> >> + div = 2;
> >> + mul_val = mul - 1;
> >> + div_val = div - 1;
> >> + /*
> >> + * Program the DCM DRP
> >> + * Step 1: Assert DCM Reset
> >> + * Step 2: Program the mul and div values in DRP
> >> + * Step 3: Read from DRP base 0x00 to restore DCM output as per
> >> + * www.xilinx.com/support/documentation/user_guides/ug191.pdf
> >> + * Step 4: De-Assert reset to DCM
> >> + */
> >> + mask = SDHC_BCLK_DCM_RST;
> >> + snps_reset_dcm(host, mask, 1);
>
> snps_reset_dcm(host, SDHC_BCLK_DCM_RST, 1);
>
OK, We will update it accordingly.
> >> +
> >> + mul_div_val = (mul_val << 8) | div_val;
>
>
> mul_div_val is also fixed?
>
> mul_val = 1, div_val = 1..then mul_div_val is 0x101?
>
As of now, mul_val and div_val are fixed to select 100MHz input frequency.
But, If we need to increase the frequency in future, we need to modify the mul_val
and div_val.
Anyway, I can use constant "mul_div_val" for the current setup.
>
> >> + sdhci_writew(host, mul_div_val, BCLK_DCM_MUL_DIV_DRP);
> >> +
> >> + reg = sdhci_readl(host, BCLK_DCM_DRP_BASE_51);
>
> just read? then
> sdhci_readl(host, BCLK_DCM_DRP_BASE_51);?
>
> If my comments are right, you can remove above parameters.
> (div, mul, div_val, mul_val, mul_div_val, reg, mask..all)
OK, We will update it accordingly.
>
> Best Regards,
> Jaehoon Chung
>
> >> +
> >> + snps_reset_dcm(host, mask, 0);
> >> +
> >> + /*
> >> + * By Default Clocks to Controller are OFF.
> >> + * Before stack applies reset; we need to turn on the clock
> >> + */
> >> + sdhci_writew(host, SDHCI_CLOCK_INT_EN,
> SDHCI_CLOCK_CONTROL);
> >> +
> >> + return 0;
> >> +
> >> +}
> >> +static struct sdhci_ops sdhci_pci_ops_snps = {
> >> + .set_clock = sdhci_set_clock_snps,
> >> +};
> >> +
> >> +int sdhci_pci_probe_slot_snps(struct sdhci_pci_slot *slot) {
> >> + int ret = 0;
> >> + struct sdhci_host *host;
> >> +
> >> + host = slot->host;
> >> + sdhci_ops = host->ops;
> >> +
> >> + sdhci_pci_ops_snps.enable_dma = sdhci_ops-
> >enable_dma;
> >> + sdhci_pci_ops_snps.set_bus_width = sdhci_ops->set_bus_width;
> >> + sdhci_pci_ops_snps.reset = sdhci_ops->reset;
> >> + sdhci_pci_ops_snps.set_uhs_signaling = sdhci_ops-
> >set_uhs_signaling;
> >> + sdhci_pci_ops_snps.hw_reset = sdhci_ops->hw_reset;
> >> +
> >> + host->ops = &sdhci_pci_ops_snps;
> >
> > I am lost. sdhci_ops is a kind of backup of the original ops from pci
> > core. Your sdhci_pci_ops_snps is a copy of ops from pci core excepting
> > set_clock and finally you update pci core ops with sdhci_pci_ops_snps.
> >
> > It seems a bit complex. At the end, unless I have missed something,
> > you have only changed set_clock from pci ops.
> >
You are correct, sdhci_pci_ops_snps is using pci core ops except set_clock.
As I mentioned at the top, We have built our own clocking logic using DCM.
So, we have to use our own set_clock function and We are reusing the pci core
ops for the reaming ops.
> >
> > Regards
> >
> > Ludovic
> >
> >> +
> >> + /* Board specific clock initialization */
> >> + ret = snps_init_clock(host);
> >> +
> >> + return ret;
> >> +}
> >> +EXPORT_SYMBOL_GPL(sdhci_pci_probe_slot_snps);
> >> diff --git a/drivers/mmc/host/sdhci-pci-dwc.h
> >> b/drivers/mmc/host/sdhci-pci-dwc.h
> >> new file mode 100644
> >> index 0000000..02e2213
> >> --- /dev/null
> >> +++ b/drivers/mmc/host/sdhci-pci-dwc.h
> >> @@ -0,0 +1,55 @@
> >> +/*
> >> + * Copyright (C) 2016 Synopsys, Inc.
> >> + *
> >> + * Author: Manjunath M B <manjumb@xxxxxxxxxxxx>
> >> + *
> >> + * This software is licensed under the terms of the GNU General
> >> +Public
> >> + * License version 2, as published by the Free Software Foundation,
> >> +and
> >> + * may be copied, distributed, and modified under those terms.
> >> + *
> >> + * This program is distributed in the hope that it will be useful,
> >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> >> + * GNU General Public License for more details.
> >> + *
> >> + */
> >> +
> >> +#ifndef __SDHCI_DWC_MSHC_PCI_H__
> >> +#define __SDHCI_DWC_MSHC_PCI_H__
> >> +
> >> +#include "sdhci-pci.h"
> >> +
> >> +#define SDHCI_UHS2_VENDOR 0xE8
> >> +
> >> +#define DRIVER_NAME "sdhci-pci-dwc"
> >> +#define SDHC_DEF_TX_CLK_PH_VAL 4
> >> +#define SDHC_DEF_RX_CLK_PH_VAL 4
> >> +
> >> +/* Synopsys Vendor Specific Registers */
> >> +#define SDHC_DBOUNCE 0x08
> >> +#define SDHC_TUNING_RX_CLK_SEL_MASK 0x000000FF
> >> +#define SDHC_GPIO_OUT 0x34
> >> +/* HAPS 51 Based implementation */
> >> +#define SDHC_BCLK_DCM_RST 0x00000001
> >> +#define SDHC_CARD_TX_CLK_DCM_RST 0x00000002
> >> +#define SDHC_TUNING_RX_CLK_DCM_RST 0x00000004
> >> +#define SDHC_TUNING_TX_CLK_DCM_RST 0x00000008
> >> +#define SDHC_TUNING_TX_CLK_SEL_MASK 0x00000070
> >> +#define SDHC_TUNING_TX_CLK_SEL_SHIFT 4
> >> +#define SDHC_TX_CLK_SEL_TUNED 0x00000080
> >> +
> >> +/* Offset of BCLK DCM DRP Attributes */
> >> +/* Every attribute is of 16 bit wide */
> >> +#define BCLK_DCM_DRP_BASE_51 0x1000
> >> +
> >> +#define BCLK_DCM_MUL_DIV_DRP 0x1050
> >> +#define MUL_MASK_DRP 0xFF00
> >> +#define DIV_MASK_DRP 0x00FF
> >> +
> >> +/* Offset of TX and RX CLK DCM DRP */
> >> +#define TXRX_CLK_DCM_DRP_BASE_51 0x2000
> >> +#define TXRX_CLK_DCM_MUL_DIV_DRP 0x2050
> >> +
> >> +int sdhci_pci_probe_slot_snps(struct sdhci_pci_slot *slot);
> >> +
> >> +#endif
> >> --
> >> 1.9.1
> >>
> > --
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> >
> >
Regards,
Prabu Thangamuthu.
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