On Dec 21, 2010, at 9:37 PM, zhangfei gao wrote:
> On Wed, Dec 22, 2010 at 12:09 AM, Philip Rakity <prakity@xxxxxxxxxxx> wrote:
>>
>> Resend as plain test -- with additional comments.
>> On Dec 21, 2010, at 4:37 AM, zhangfei gao wrote:
>>
>>> v3: sync to mmc-next
>>>
>>> Emmc speed could double if using ddr50 mode, help check
>>>
>>> From 895c3d15a200d5f5803f992dab46ff114ad26f90 Mon Sep 17 00:00:00 2001
>>> From: Zhangfei Gao <zhangfei.gao@xxxxxxxxxxx>
>>> Date: Tue, 21 Dec 2010 19:51:38 -0500
>>> Subject: [PATCH] mmc: sdhci support emmc ddr50 mode
>>>
>>> 1. spec sdhc 3.0 does not claim support 1.2v ddr mode
>>> 2. Call back function set_power is added, since some controller count
>>> on external pmic to provide power
>>> 3. According to spec sdhc 3.0, uhs mode, including emmc ddr50 takes
>>> effect only when 1.8v Signaling Enable bit, which used for providing
>>> 1.8v.
>>> So emmc ddr50 mode works after 1.8v switching process, though emmc
>>> ddr50 could work at high voltage such as 3.3v if external pmic provide
>>> voltage.
>>> Limitation: emmc ddr50 mode only workable when both host and emmc
>>> card support 1.70-1.90v
>>
>>
>> signaling voltage is not the same as card voltage. card voltage can be 3.3v and
>> signaling voltage 1.8v.
> My understanding is signal voltage is io voltage, which could be low
> voltage, 1.70~1.90v.
> Card voltage should be keeps high voltage.
> In fact, two power domain inside emmc, one is vcc, the other is vccq,
> this is control io domain.
>>
>>> 4. According to JESD84, power down and power up is required to
>>> provide low voltage 1.70-1.90v to mmc.
>>>
>>> Verified: toshiba emmc on mmp2, with io voltage at 1.8v provided by
>>> external pmic.
>>>
>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxxx>
>>> ---
>>> drivers/mmc/core/core.c | 13 +++++++++++++
>>> drivers/mmc/core/core.h | 1 +
>>> drivers/mmc/core/mmc.c | 6 +++++-
>>> drivers/mmc/host/sdhci.c | 44 +++++++++++++++++++++++++++++++++++++++++---
>>> drivers/mmc/host/sdhci.h | 14 +++++++++++++-
>>> 5 files changed, 73 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
>>> index a8e89f3..fd657f1 100644
>>> --- a/drivers/mmc/core/core.c
>>> +++ b/drivers/mmc/core/core.c
>>> @@ -1012,6 +1012,19 @@ static void mmc_power_off(struct mmc_host *host)
>>> }
>>>
>>> /*
>>> + * mmc select low voltage 1.70-1.95v
>>> + */
>>> +void mmc_select_low_voltage(struct mmc_host *host, u32 ocr)
>>> +{
>>> + if (!(ocr & MMC_VDD_165_195))
>>> + return;
>>> +
>>> + mmc_power_off(host);
>>> + host->ocr = ocr & host->ocr_avail;
>>> + mmc_power_up(host);
>>> +}
>>> +
>>> +/*
>>> * Cleanup when the last reference to the bus operator is dropped.
>>> */
>>> static void __mmc_release_bus(struct mmc_host *host)
>>> diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
>>> index 026c975..b05c20a 100644
>>> --- a/drivers/mmc/core/core.h
>>> +++ b/drivers/mmc/core/core.h
>>> @@ -41,6 +41,7 @@ void mmc_set_bus_width(struct mmc_host *host,
>>> unsigned int width);
>>> void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width,
>>> unsigned int ddr);
>>> u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
>>> +void mmc_select_low_voltage(struct mmc_host *host, u32 ocr);
>>> void mmc_set_timing(struct mmc_host *host, unsigned int timing);
>>>
>>> static inline void mmc_delay(unsigned int ms)
>>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>>> index 86cac0d..8779339 100644
>>> --- a/drivers/mmc/core/mmc.c
>>> +++ b/drivers/mmc/core/mmc.c
>>> @@ -790,7 +790,11 @@ int mmc_attach_mmc(struct mmc_host *host, u32 ocr)
>>> ocr &= ~0x7F;
>>> }
>>>
>>> - host->ocr = mmc_select_voltage(host, ocr);
>>> + if ((ocr & MMC_VDD_165_195)
>>> + && (host->ocr_avail & MMC_VDD_165_195))
>>> + mmc_select_low_voltage(host, ocr);
>>> + else
>>> + host->ocr = mmc_select_voltage(host, ocr);
>>>
>>
>> The patch for dual voltage cards should be a separate patch. It is independent of
>> support for dual data rate.
>>
>>> /*
>>> * Can we support the voltage of the card?
>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>>> index d5febe5..aafbb42 100644
>>> --- a/drivers/mmc/host/sdhci.c
>>> +++ b/drivers/mmc/host/sdhci.c
>>> @@ -986,6 +986,22 @@ static void sdhci_finish_command(struct sdhci_host *host)
>>> host->cmd = NULL;
>>> }
>>>
>>> +static void sdhci_set_ddr(struct sdhci_host *host, unsigned int ddr)
>>> +{
>>> + u16 con;
>>> +
>>> + if (ddr == MMC_SDR_MODE)
>>> + return;
>>> +
>>> + con = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>> + if (con & SDHCI_CTRL2_1_8V) {
>>> + con &= ~SDHCI_CTRL2_UHS_MASK;
>>> + if (ddr & MMC_1_8V_DDR_MODE)
>>> + con |= SDHCI_CTRL2_DDR50;
>>> + sdhci_writew(host, con, SDHCI_HOST_CONTROL2);
>>> + }
>>> +}
>>> +
>>> static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
>>> {
>>> int div;
>>> @@ -1084,6 +1100,18 @@ static void sdhci_set_power(struct sdhci_host
>>> *host, unsigned short power)
>>> return;
>>> }
>>>
>>> + if ((pwr == SDHCI_POWER_180) &&
>>> + (host->mmc->caps & MMC_CAP_1_8V_DDR)) {
>>> + u16 con;
>>> +
>>> + con = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>>> + con |= SDHCI_CTRL2_1_8V;
>>> + sdhci_writew(host, con, SDHCI_HOST_CONTROL2);
>>> +
>>> + if (host->ops->set_power)
>>> + host->ops->set_power(host, pwr);
>>> + }
>>> +
>>
>> power to the card can be at 3.3v and signaling at 1.8v. This is a legal combination.
>
> It is legal combination, then why here should be reworked?
> The Power control register is control SD bus voltage, which should be
> io voltage.
> Even the dual voltage emmc card can not work at both vcc and vccq are 1.8v.
>
>> The
>>> + if ((pwr == SDHCI_POWER_180) &&
>>> + (host->mmc->caps & MMC_CAP_1_8V_DDR)) {
>> should be reworked.
>>
>>> /*
>>> * Spec says that we should clear the power reg before setting
>>> * a new value. Some controllers don't seem to like this though.
>>> @@ -1180,6 +1208,7 @@ static void sdhci_set_ios(struct mmc_host *mmc,
>>> struct mmc_ios *ios)
>>> }
>>>
>>> sdhci_set_clock(host, ios->clock);
>>> + sdhci_set_ddr(host, ios->ddr);
>>>
>>> if (ios->power_mode == MMC_POWER_OFF)
>>> sdhci_set_power(host, -1);
>>> @@ -1744,7 +1773,7 @@ EXPORT_SYMBOL_GPL(sdhci_alloc_host);
>>> int sdhci_add_host(struct sdhci_host *host)
>>> {
>>> struct mmc_host *mmc;
>>> - unsigned int caps, ocr_avail;
>>> + unsigned int caps, caps_h = 0, ocr_avail;
>>> int ret;
>>>
>>> WARN_ON(host == NULL);
>>> @@ -1767,8 +1796,17 @@ int sdhci_add_host(struct sdhci_host *host)
>>> host->version);
>>> }
>>>
>>> - caps = (host->quirks & SDHCI_QUIRK_MISSING_CAPS) ? host->caps :
>>> - sdhci_readl(host, SDHCI_CAPABILITIES);
>>> + if (host->quirks & SDHCI_QUIRK_MISSING_CAPS)
>>> + caps = host->caps;
>>> + else {
>>> + caps = sdhci_readl(host, SDHCI_CAPABILITIES);
>>> + caps_h = sdhci_readl(host, SDHCI_CAPABILITIES_1);
>>> + }
>>> +
>>> + if (caps & SDHCI_CAN_VDD_180) {
>>> + if (caps_h & SDHCI_CAN_SDR50)
>>> + mmc->caps |= (MMC_CAP_1_8V_DDR);
>>> + }
>>>
>>> if (host->quirks & SDHCI_QUIRK_FORCE_DMA)
>>> host->flags |= SDHCI_USE_SDMA;
>>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>>> index 6e0969e..c4bd5dd 100644
>>> --- a/drivers/mmc/host/sdhci.h
>>> +++ b/drivers/mmc/host/sdhci.h
>>> @@ -145,7 +145,14 @@
>>>
>>> #define SDHCI_ACMD12_ERR 0x3C
>>>
>>> -/* 3E-3F reserved */
>>> +#define SDHCI_HOST_CONTROL2 0x3E
>>> +#define SDHCI_CTRL2_UHS_MASK 0x0007
>>> +#define SDHCI_CTRL2_SDR12 0x0000
>>> +#define SDHCI_CTRL2_SDR25 0x0001
>>> +#define SDHCI_CTRL2_SDR50 0x0002
>>> +#define SDHCI_CTRL2_SDR104 0x0003
>>> +#define SDHCI_CTRL2_DDR50 0x0004
>>> +#define SDHCI_CTRL2_1_8V 0x0008
>>>
>>> #define SDHCI_CAPABILITIES 0x40
>>> #define SDHCI_TIMEOUT_CLK_MASK 0x0000003F
>>> @@ -167,6 +174,9 @@
>>> #define SDHCI_CAN_64BIT 0x10000000
>>>
>>> #define SDHCI_CAPABILITIES_1 0x44
>>> +#define SDHCI_CAN_SDR50 0x00000001
>>> +#define SDHCI_CAN_SDR104 0x00000002
>>> +#define SDHCI_CAN_DDR50 0x00000004
>>>
>>> #define SDHCI_MAX_CURRENT 0x48
>>>
>>> @@ -222,6 +232,8 @@ struct sdhci_ops {
>>> void (*platform_send_init_74_clocks)(struct sdhci_host *host,
>>> u8 power_mode);
>>> unsigned int (*get_ro)(struct sdhci_host *host);
>>> + unsigned int (*set_power)(struct sdhci_host *host,
>>> + unsigned short power);
>>> };
>>>
>>> #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
>>> --
>>> 1.7.0.4
>>> <0001-mmc-sdhci-support-emmc-ddr50-mode.patch>
>>
>>
commented out support for 1.8v in sdhci.c where the check was made for the controller supporting 1.8v core voltage
added printk to show ocr and host->ocr. before check to call mmc_select_low_voltage or mmc_select_voltage in mmc.c
the card is recognized as DDR but we do not mount the drive since the check for SDHCI_POWER_180 fails and we do not program the registers.
[ 0.000000] Linux version 2.6.37-rc6-next-20101220-00023-ge7c195e-dirty (philip@philip-laptop) (gcc version 4.2.0 20070413 (prerelease) (CodeSourcery 2007q1-10. Marvell 2009q3-18 20090821)) #80 PREEMPT 0
[ 0.000000] CPU: Marvell PJ4 processor [560f5815] revision 5 (ARMv7), cr=00c5387f
[ 0.000000] CPU: VIPT nonaliasing data cache, VIPT aliasing instruction cache
[ 0.000000] Machine: Brownstone Development Platform
[ 0.000000] Ignoring unrecognised tag 0x41000403
[ 0.000000] Memory policy: ECC disabled, Data cache writeback
[ 0.000000] On node 0 totalpages: 131072
[ 0.000000] free_area_init_node: node 0, pgdat c03713d8, node_mem_map c0390000
[ 0.000000] Normal zone: 1024 pages used for memmap
[ 0.000000] Normal zone: 0 pages reserved
[ 0.000000] Normal zone: 130048 pages, LIFO batch:31
[ 0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768
[ 0.000000] pcpu-alloc: [0] 0
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 130048
[ 0.000000] Kernel command line: debug rootdelay=15 root=/dev/mmcblk0p1 rootfstype=ext3 console=ttyS2,38400 mem=512M uart_dma mbr_offset=0x4800
[ 0.000000] PID hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.000000] Dentry cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.000000] Inode-cache hash table entries: 32768 (order: 5, 131072 bytes)
[ 0.000000] Memory: 512MB = 512MB total
[ 0.000000] Memory: 516108k/516108k available, 8180k reserved, 0K highmem
[ 0.000000] Virtual kernel memory layout:
[ 0.000000] vector : 0xffff0000 - 0xffff1000 ( 4 kB)
[ 0.000000] fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
[ 0.000000] DMA : 0xffc00000 - 0xffe00000 ( 2 MB)
[ 0.000000] vmalloc : 0xe0800000 - 0xfe000000 ( 472 MB)
[ 0.000000] lowmem : 0xc0000000 - 0xe0000000 ( 512 MB)
[ 0.000000] modules : 0xbf000000 - 0xc0000000 ( 16 MB)
[ 0.000000] .init : 0xc0008000 - 0xc001f000 ( 92 kB)
[ 0.000000] .text : 0xc001f000 - 0xc035400c (3285 kB)
[ 0.000000] .data : 0xc0356000 - 0xc0373040 ( 117 kB)
[ 0.000000] Preemptable hierarchical RCU implementation.
[ 0.000000] RCU-based detection of stalled CPUs is disabled.
[ 0.000000] Verbose stalled-CPUs detection is disabled.
[ 0.000000] NR_IRQS:320 nr_irqs:360 360
[ 0.000000] sched_clock: 32 bits at 6MHz, resolution 153ns, wraps every 660764ms
[ 0.000000] Console: colour dummy device 80x30
[ 0.000166] Calibrating delay loop... 796.26 BogoMIPS (lpj=3981312)
[ 0.220135] pid_max: default: 32768 minimum: 301
[ 0.220328] Mount-cache hash table entries: 512
[ 0.220328] CPU: Testing write buffer coherency: ok
[ 0.224398] print_constraints: dummy: regulator:
[ 0.224525] NET: Registered protocol family 16
[ 0.224525] Tauros2: Disabling L2 prefetch.
[ 0.224569] Tauros2: L2 cache support initialised in ARMv6 mode.
[ 0.227737] bio: create slab <bio-0> at 0
[ 0.228950] Switching to clocksource clocksource
[ 0.233848] NET: Registered protocol family 2
[ 0.234150] IP route cache hash table entries: 4096 (order: 2, 16384 bytes)
[ 0.234482] TCP established hash table entries: 16384 (order: 5, 131072 bytes)
[ 0.234482] TCP bind hash table entries: 16384 (order: 4, 65536 bytes)
[ 0.234733] TCP: Hash tables configured (established 16384 bind 16384)
[ 0.234863] TCP reno registered
[ 0.234878] UDP hash table entries: 256 (order: 0, 4096 bytes)
[ 0.234878] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
[ 0.234901] NET: Registered protocol family 1
[ 0.235444] RPC: Registered udp transport module.
[ 0.235444] RPC: Registered tcp transport module.
[ 0.235462] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 0.237177] JFFS2 version 2.2. (NAND) .. 2001-2006 Red Hat, Inc.
[ 0.237177] msgmni has been set to 1008
[ 0.238053] io scheduler noop registered
[ 0.238087] io scheduler deadline registered
[ 0.238104] io scheduler cfq registered (default)
[ 0.238679] pxa2xx-uart.0: ttyS0 at MMIO 0xd4030000 (irq = 27) is a FFUART
[ 0.238852] pxa2xx-uart.2: ttyS2 at MMIO 0xd4018000 (irq = 24) is a STUART
[ 1.353048] console [ttyS2] enabled
[ 1.364154] mousedev: PS/2 mouse device common for all mice
[ 1.380867] sdhci: Secure Digital Host Controller Interface driver
[ 1.399304] sdhci: Copyright(c) Pierre Ossman
[ 1.412378] mmc0: no vmmc regulator found
[ 1.424539] mmc0: SDHCI controller on MMC [sdhci-pxa.2] using ADMA
[ 1.443030] mmc1: no vmmc regulator found
[ 1.455203] mmc1: SDHCI controller on MMC [sdhci-pxa.0] using ADMA
[ 1.474554] mmc2: no vmmc regulator found
[ 1.486636] mmc2: SDHCI controller on MMC [sdhci-pxa.1] using ADMA
[ 1.505238] TCP cubic registered
[ 1.514889] NET: Registered protocol family 17
[ 1.529176] Registering the dns_resolver key type
[ 1.545330] VFP support v0.3: implementor 56 architecture 2 part 20 variant 9 rev 5
[ 1.568612] drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
[ 1.587543] Waiting 15sec before mounting root device...
[ 1.604984] mmc_attach_mmc:mmc0: ocr & MMC_VDD_165_195 = 80, host->ocr_avail & MMC_VDD_165_195 = 0
[ 11.688964] mmc0: Timeout waiting for hardware interrupt.
[ 11.688976] sdhci: =========== REGISTER DUMP (mmc0)===========
[ 11.705024] sdhci: Sys addr: 0x00000000 | Version: 0x00000002
[ 11.739657] sdhci: Blk size: 0x00007008 | Blk cnt: 0x00000000
[ 11.739657] sdhci: Argument: 0x00000000 | Trn mode: 0x00000003
[ 11.756973] sdhci: Present: 0x01fa0000 | Host ctl: 0x00000035
[ 11.791607] sdhci: Power: 0x0000000f | Blk gap: 0x00000000
[ 11.791607] sdhci: Wake-up: 0x00000000 | Clock: 0x00000207
[ 11.808923] sdhci: Timeout: 0x0000000e | Int stat: 0x00000000
[ 11.826241] sdhci: Int enab: 0x02ff000b | Sig enab: 0x02ff000b
[ 11.843558] sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000
[ 11.860874] sdhci: Caps: 0x25fcc8b2 | Caps_1: 0x00002f77
[ 11.878191] sdhci: Cmd: 0x0000133a | Max curr: 0x00000000
[ 11.895509] sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x1f943808
[ 11.912826] sdhci: ===========================================
[ 11.947936] mmc0: new high speed DDR MMC card at address 0001
[ 11.965402] mmcblk0: mmc0:0001 SEM08G 7.39 GiB
[ 11.983931] mmcblk0: retrying using single block read
[ 11.999498] mmcblk0: error -84 transferring data, sector 0, nr 8, card status 0x900
[ 12.022300] end_request: I/O error, dev mmcblk0, sector 0
[ 12.038868] mmcblk0: error -84 transferring data, sector 1, nr 7, card status 0x900
[ 12.061745] end_request: I/O error, dev mmcblk0, sector 1
[ 12.078364] mmcblk0: error -84 transferring data, sector 2, nr 6, card status 0x900
[ 12.101155] end_request: I/O error, dev mmcblk0, sector 2
[ 12.117704] mmcblk0: error -84 transferring data, sector 3, nr 5, card status 0x900
[ 12.140507] end_request: I/O error, dev mmcblk0, sector 3
[ 12.157063] mmcblk0: error -84 transferring data, sector 4, nr 4, card status 0x900
[ 12.179876] end_request: I/O error, dev mmcblk0, sector 4
[ 12.196428] mmcblk0: error -84 transferring data, sector 5, nr 3, card status 0x900
[ 12.219233] end_request: I/O error, dev mmcblk0, sector 5
[ 12.235789] mmcblk0: error -84 transferring data, sector 6, nr 2, card status 0x900
[ 12.258604] end_request: I/O error, dev mmcblk0, sector 6
[ 12.275154] mmcblk0: error -84 transferring data, sector 7, nr 1, card status 0x900
[ 12.297970] end_request: I/O error, dev mmcblk0, sector 7
[ 12.314016] Buffer I/O error on device mmcblk0, logical block 0
[ 12.332239] mmcblk0: retrying using single block read
[ 12.347777] mmcblk0: error -84 transferring data, sector 0, nr 8, card status 0x900
[ 12.370589] end_request: I/O error, dev mmcblk0, sector 0
[ 12.387149] mmcblk0: error -84 transferring data, sector 1, nr 7, card status 0x900
[ 12.409954] end_request: I/O error, dev mmcblk0, sector 1
[ 12.426510] mmcblk0: error -84 transferring data, sector 2, nr 6, card status 0x900
[ 12.449325] end_request: I/O error, dev mmcblk0, sector 2
[ 12.465891] mmcblk0: error -84 transferring data, sector 3, nr 5, card status 0x900
[ 12.488677] end_request: I/O error, dev mmcblk0, sector 3
[ 12.505239] mmcblk0: error -84 transferring data, sector 4, nr 4, card status 0x900
[ 12.528050] end_request: I/O error, dev mmcblk0, sector 4
[ 12.544602] mmcblk0: error -84 transferring data, sector 5, nr 3, card status 0x900
[ 12.567407] end_request: I/O error, dev mmcblk0, sector 5
[ 12.583965] mmcblk0: error -84 transferring data, sector 6, nr 2, card status 0x900
[ 12.606770] end_request: I/O error, dev mmcblk0, sector 6
[ 12.623330] mmcblk0: error -84 transferring data, sector 7, nr 1, card status 0x900
[ 12.646134] end_request: I/O error, dev mmcblk0, sector 7
[ 12.662188] Buffer I/O error on device mmcblk0, logical block 0
[ 12.679810] mmcblk0: unable to read partition table
[ 16.609127] VFS: Cannot open root device "mmcblk0p1" or unknown-block(179,1)
[ 16.630132] Please append a correct "root=" boot option; here are the available partitions:
[ 16.654964] b300 7757824 mmcblk0 driver: mmcblk
[ 16.670806] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,1)
[ 16.695905] [<c002abe8>] (unwind_backtrace+0x0/0x124) from [<c0038518>] (panic+0x6c/0x18c)
[ 16.720516] [<c0038518>] (panic+0x6c/0x18c) from [<c0008d94>] (mount_block_root+0x1c4/0x204)
[ 16.745636] [<c0008d94>] (mount_block_root+0x1c4/0x204) from [<c0008e74>] (mount_root+0xa0/0xc4)
[ 16.771787] [<c0008e74>] (mount_root+0xa0/0xc4) from [<c0008fb4>] (prepare_namespace+0x11c/0x174)
[ 16.798201] [<c0008fb4>] (prepare_namespace+0x11c/0x174) from [<c0008750>] (kernel_init+0x108/0x14c)
[ 16.825393] [<c0008750>] (kernel_init+0x108/0x14c) from [<c00263e0>] (kernel_thread_exit+0x0/0x8)
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