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* sunxi: Use CONFIG_MACH_SUN?I from Kconfig instead of CONFIG_SUN?IIan Campbell2014-11-051-17/+17
| | | | | | | | | | | Mostly automatic with: sed -i -e 's/CONFIG_\(SUN[45678]I\)/CONFIG_MACH_\1/g' $(git grep -l CONFIG_SUN[45678]I) followed by removing the relevant #defines from include/configs/sun?i.h by hand. Signed-off-by: Ian Campbell <ijc@hellion.org.uk> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: Add CONFIG_OLD_SUNXI_KERNEL_COMPAT Kconfig optionHans de Goede2014-10-241-0/+4
| | | | | | | | | | | | | | Add a Kconfig option which users can select when they want to boot older kernels, e.g. the linux-sunxi 3.4 kernels. For now this just forces the pll5 "p" value to 1 (divide by 2) as that is what those kernels are hardcoded too, in the future this may enable further workarounds. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Tom Rini <trini@ti.com> -- Changes in v2: -s/CONFIG_OLD_KERNEL_COMPAT/CONFIG_OLD_SUNXI_KERNEL_COMPAT. -Move the code block setting P(1) for old kernels to where P gets cleared
* sunxi: dram: Use clock_get_pll5p to calculate mbus, rather then hardcodingHans de Goede2014-10-241-18/+14
| | | | | | | | This is a preparation patch for making the pll5 "p" divisor configurable through Kconfig. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
* sunxi: dram: Autodetect DDR3 bus width and densitySiarhei Siamashka2014-08-121-5/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case if the 'dram_para' struct does not specify the exact bus width or chip density, just use a trial and error method to find a usable configuration. Because all the major bugs in the DRAM initialization sequence are now hopefully fixed, it should be safe to re-initialize the DRAM controller multiple times until we get it configured right. The original Allwinner's boot0 bootloader also used a similar autodetection trick. The DDR3 spec contains the package pinout and addressing table for different possible chip densities. It appears to be impossible to distinguish between a single chip with 16 I/O data lines and a pair of chips with 8 I/O data lines in the case if they provide the same storage capacity. Because a single 16-bit chip has a higher density than a pair of equivalent 8-bit chips, it has stricter refresh timings. So in the case of doubt, we assume that 16-bit chips are used. Additionally, only Allwinner A20 has all A0-A15 address lines and can support densities up to 8192. The older Allwinner A10 and Allwinner A13 can only support densities up to 4096. We deliberately leave out DDR2, dual-rank configurations and the special case of a 8-bit chip with density 8192. None of these configurations seem to have been ever used in real devices. And no new devices are likely to use these exotic configurations (because only up to 2GB of RAM can be populated in any case). This DRAM autodetection feature potentially allows to have a single low performance fail-safe DDR3 initialiazation for a universal single bootloader binary, which can be compatible with all Allwinner A10/A13/A20 based devices (if the ifdefs are replaced with a runtime SoC type detection). Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Derive write recovery delay from DRAM clock speedSiarhei Siamashka2014-08-121-1/+16
| | | | | | | | | | | The write recovery time is 15ns for all JEDEC DDR3 speed bins. And instead of hardcoding it to 10 cycles, it is possible to set tighter timings based on accurate calculations. For example, DRAM clock frequencies up to 533MHz need only 8 cycles for write recovery. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Drop DDR2 support and assume only single rank DDR3 memorySiarhei Siamashka2014-08-121-22/+19
| | | | | | | | | | | | | | | | | All the known Allwinner A10/A13/A20 devices are using just single rank DDR3 memory. So don't pretend that we support DDR2 or more than one rank, because nobody could ever test these configurations for real and they are likely broken. Support for these features can be added back in the case if such hardware actually exists. As part of this code cleanup, also replace division by 1024 with division by 1000 for the refresh timing calculations. This allows to use the original non-skewed tRFC timing table from the DRR3 spec and make code less confusing. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Configurable DQS gating window mode and delaySiarhei Siamashka2014-08-121-1/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The hardware DQS gate training is a bit unreliable and does not always find the best delay settings. So we introduce a 32-bit 'dqs_gating_delay' variable, where each byte encodes the DQS gating delay for each byte lane. The delay granularity is 1/4 cycle. Also we allow to enable the active DQS gating window mode, which works better than the passive mode in practice. The DDR3 spec says that there is a 0.9 cycles preamble and 0.3 cycle postamble. The DQS window has to be opened during preamble and closed during postamble. In the passive window mode, the gating window is opened and closed by just using the gating delay settings. And because of the 1/4 cycle delay granularity, accurately hitting the 0.3 cycle long postamble is a bit tough. In the active window mode, the gating window is auto-closing with the help of monitoring the DQS line, which relaxes the gating delay accuracy requirements. But the hardware DQS gate training is still performed in the passive window mode. It is a more strict test, which is reducing the results variance compared to the training with active window mode. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Add a helper function 'mctl_get_number_of_lanes'Siarhei Siamashka2014-08-121-11/+16
| | | | | | | | It is going to be useful in more than one place. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Improve DQS gate data training error handlingSiarhei Siamashka2014-08-121-2/+0
| | | | | | | | | | | The stale error status should be cleared for all sun4i/sun5i/sun7i hardware and not just for sun7i. Also there are two types of DQS gate training errors ("found no result" and "found more than one possible result"). Both are handled now. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Use divisor P=1 for PLL5Siarhei Siamashka2014-08-121-17/+11
| | | | | | | | | | | This configures the PLL5P clock frequency to something in the ballpark of 1GHz and allows more choices for MBUS and G2D clock frequency selection (using their own divisors). In particular, it enables the use of 2/3 clock speed ratio between MBUS and DRAM. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Configurable MBUS clock speed (use PLL5 or PLL6)Siarhei Siamashka2014-08-121-14/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sun5i hardware (Allwinner A13) introduced configurable MBUS clock speed. Allwinner A13 uses only 16-bit data bus width to connect the external DRAM, which is halved compared to the 32-bit data bus of sun4i (Allwinner A10), so it does not make much sense to clock a wider internal bus at a very high speed. The Allwinner A13 manual specifies 300 MHz MBUS clock speed limit and 533 MHz DRAM clock speed limit. Newer sun7i hardware (Allwinner A20) has a full width 32-bit external memory interface again, but still keeps the MBUS clock speed configurable. Clocking MBUS too low inhibits memory performance and one has to find the optimal MBUS/DRAM clock speed ratio, which may depend on many factors: http://linux-sunxi.org/A10_DRAM_Controller_Performance This patch introduces a new 'mbus_clock' parameter for the 'dram_para' struct and uses it as a desired MBUS clock speed target. If 'mbus_clock' is not set, 300 MHz is used by default to match the older hardcoded settings. PLL5P and PLL6 are both evaluated as possible clock sources. Preferring the one, which can provide higher clock frequency that is lower or equal to the 'mbus_clock' target. In the case of a tie, PLL5P has higher priority. Attempting to set the MBUS clock speed has no effect on sun4i, but does no harm either. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Re-introduce the impedance calibration ond ODTSiarhei Siamashka2014-08-121-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | The DRAM controller allows to configure impedance either by using the calibration against an external high precision 240 ohm resistor, or by skipping the calibration and loading pre-defined data. The DRAM controller register guide is available here: http://linux-sunxi.org/A10_DRAM_Controller_Register_Guide#SDR_ZQCR0 The new code supports both of the impedance configuration modes: - If the higher bits of the 'zq' parameter in the 'dram_para' struct are zero, then the lowest 8 bits are used as the ZPROG value, where two divisors encoded in lower and higher 4 bits. One divisor is used for calibrating the termination impedance, and another is used for the output impedance. - If bits 27:8 in the 'zq' parameters are non-zero, then they are used as the pre-defined ZDATA value instead of performing the ZQ calibration. Two lowest bits in the 'odt_en' parameter enable ODT for the DQ and DQS lines individually. Enabling ODT for both DQ and DQS means that the 'odt_en' parameter needs to be set to 3. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Add 'await_bits_clear'/'await_bits_set' helper functionsSiarhei Siamashka2014-08-121-6/+22
| | | | | | | | | | | | The old 'await_completion' function is not sufficient, because in some cases we want to wait for bits to be cleared, and in the other cases we want to wait for bits to be set. So split the 'await_completion' into two new 'await_bits_clear' and 'await_bits_set' functions. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Do DDR3 reset in the same way on sun4i/sun5i/sun7iSiarhei Siamashka2014-08-121-11/+0
| | | | | | | | | | | The older differences were likely justified by the need to mitigate the CKE delay timing violations on sun4i/sun5i. The CKE problem is already resolved, so now we can use the sun7i variant of this code everywhere. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Remove broken impedance and ODT configuration codeSiarhei Siamashka2014-08-121-27/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can safely remove it, because none of the currently supported boards uses these features. The existing implementation had multiple problems: - unnecessary code duplication between sun4i/sun5i/sun7i - ZQ calibration was never initiated explicitly, and could be only triggered by setting the highest bit in the 'zq' parameter in the 'dram_para' struct (this was never actually done for any of the known Allwinner devices). - even if the ZQ calibration could be started, no attempts were made to wait for its completion, or checking whether the default automatically initiated ZQ calibration is still in progress - ODT was only ever enabled on sun4i, but not on sun5i/sun7i Additionally, SDR_IOCR was set to 0x00cc0000 only on sun4i. There are some hints in the Rockchip Linux kernel sources, indicating that these bits are related to the automatic I/O power down feature, which is poorly understood on sunxi hardware at the moment. Avoiding to set these bits on sun4i too does not seem to have any measurable/visible impact. The impedance and ODT configuration code will be re-introdeced in one of the next comits. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Fix CKE delay handling for sun4i/sun5iSiarhei Siamashka2014-08-121-7/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before driving the CKE pin (Clock Enable) high, the DDR3 spec requires to wait for additional 500 us after the RESET pin is de-asserted. The DRAM controller takes care of this delay by itself, using a configurable counter in the SDR_IDCR register. This works in the same way on sun4i/sun5i/sun7i hardware (even the default register value 0x00c80064 is identical). Except that the counter is ticking a bit slower on sun7i (3 DRAM clock cycles instead of 2), resulting in longer actual delays for the same settings. This patch configures the SDR_IDCR register for all sun4i/sun5i/sun7i SoC variants and not just for sun7i alone. Also an explicit udelay(500) is added immediately after DDR3 reset for extra safety. This is a duplicated functionality. But since we don't have perfect documentation, it may be reasonable to play safe. Half a millisecond boot time increase is not that significant. Boot time can be always optimized later. Preferebly by the people, who have the hardware equipment to check the actual signals on the RESET and CKE lines and verify all the timings. The old code did not configure the SDR_IDCR register for sun4i/sun5i, but performed the DDR3 reset very early for sun4i/sun5i. This resulted in a larger time gap between the DDR3 reset and the DDR3 initialization steps and reduced the chances of CKE delay timing violation to cause real troubles. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Respect the DDR3 reset timing requirementsSiarhei Siamashka2014-08-121-2/+7
| | | | | | | | | | | | | | The RESET pin needs to be kept low for at least 200 us according to the DDR3 spec. So just do it the right way. This issue did not cause any visible major problems earlier, because the DRAM RESET pin is usually already low after the board reset. And the time gap before reaching the sunxi u-boot DRAM initialization code appeared to be sufficient. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Remove broken super-standby remnantsSiarhei Siamashka2014-08-121-46/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | If the dram->ppwrsctl (SDR_DPCR) register has the lowest bit set to 1, this means that DRAM is currently in self-refresh mode and retaining the old data. Since we have no idea what to do in this situation yet, just set this register to 0 and initialize DRAM in the same way as on any normal reboot (discarding whatever was stored there). This part of code was apparently used by the Allwinner boot0 bootloader to handle resume from the so-called super-standby mode. But this particular code got somehow mangled on the way from the boot0 bootloader to the u-boot-sunxi bootloader and has no chance of doing anything even remotely sane. For example: 1. in the original boot0 code we had "mctl_write_w(SDR_DPCR, 0x16510000)" (write to the register) and in the u-boot it now looks like "setbits_le32(&dram->ppwrsctl, 0x16510000)" (set bits in the register) 2. in the original boot0 code it was issuing three commands "0x12, 0x17, 0x13" (Self-Refresh entry, Self-Refresh exit, Refresh), but in the u-boot they have become "0x12, 0x12, 0x13" (Self-Refresh entry, Self-Refresh entry, Refresh) Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: dram: Remove useless 'dramc_scan_dll_para()' functionSiarhei Siamashka2014-08-121-124/+1
| | | | | | | | | | | | | | | | | | | | The attempt to do DRAM parameters calibration in 'dramc_scan_dll_para()' function by trying different DLL adjustments and using the hardware DQS gate training result as a feedback is a great source of inspiration, but it just can't work properly the way it is implemented now. The fatal problem of this implementation is that the DQS gating window can be successfully found for almost every DLL delay adjustment setup that gets tried. Thus making it unable to see any real difference between 'good' and 'bad' settings. Also this code was supposed to be only activated by setting the highest bit in the 'dram_tpr3' variable of the 'dram_para' struct (per-board dram configuration). But none of the linux-sunxi devices has ever used it for real. Basically, this code is just a dead weight. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
* sunxi: Add sun5i supportHans de Goede2014-07-061-0/+21
| | | | | | | | | | | | | | | | | | | Add support for the Allwinner A13 and A10s SoCs also know as the Allwinner sun5i family, and the A13-OLinuXinoM A13 based and r7-tv-dongle A10s based boards. The only differences compared to the already supported sun4i and sun7i families are all in the DRAM controller initialization: -Different hcpr values -Different MBUS settings -Some other small initialization changes Signed-off-by: Henrik Nordstrom <henrik@henriknordstrom.net> Signed-off-by: Stefan Roese <sr@denx.de> Signed-off-by: Oliver Schinagl <oliver@schinagl.nl> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
* sunxi: Add sun4i supportHans de Goede2014-07-061-3/+78
| | | | | | | | | | | | | | | | | Add support for the Allwinner A10 SoC also known as the Allwinner sun4i family, and add the Cubieboard board which uses the A10 SoC. Compared to sun7 only the DRAM controller is a bit different: -Controller reset bits are inverted, but only for Rev. A -Different hpcr values -No MBUS on sun4i -Various other initialization changes Signed-off-by: Henrik Nordstrom <henrik@henriknordstrom.net> Signed-off-by: Stefan Roese <sr@denx.de> Signed-off-by: Oliver Schinagl <oliver@schinagl.nl> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
* sunxi: add sun7i dram setup supportIan Campbell2014-05-251-0/+593
This patch adds DRAM initialisation support for the Allwinner A20 (sun7i) processor. This code will not been compiled until the build is hooked up in a later patch. It has been split out to keep the patches manageable. Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Signed-off-by: Emilio López <emilio@elopez.com.ar> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Henrik Nordstrom <henrik@henriknordstrom.net> Signed-off-by: Jens Kuske <jenskuske@gmail.com> Signed-off-by: Luke Leighton <lkcl@lkcl.net> Signed-off-by: Oliver Schinagl <oliver@schinagl.nl> Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Signed-off-by: Stefan Roese <sr@denx.de> Signed-off-by: Ian Campbell <ijc@hellion.org.uk> Reviewed-by: Marek Vasut <marex@denx.de> Cc: Tom Cubie <Mr.hipboi@gmail.com> Reviewed-by: Tom Rini <trini@ti.com>
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