Unit BCMSDHOST
From Ultibo.org
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Description
Broadcom BCM27XX SDHOST driver
The SDHOST controller on the BCM27XX is a non SDHCI-compliant device which requires a specific driver.
It can be routed to GPIO pins 22 to 27 (ALT0) or 48 to 53 (ALT0) in order to control the SD card slot when the SDHCI device is being used for the on board WiFi.
Note that on the Raspberry Pi 4 the SD card is no longer connected to pins 48 to 53 so the SDHOST controller cannot control the primary SD card, there is an additional SDHCI controller (EMMC2) for that purpose.
Constants
To be documented
Type definitions
BCMSDHOST mailbox tag request
TBCMSDHOSTMailboxTagSetSDHostClock = record
| Mailbox tag request for BCMSDHOST_MBOX_TAG_SET_SDHOST_CLOCK | |
Clock:LongWord;
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Value1:LongWord;
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Value2:LongWord;
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BCMSDHOST host
PBCMSDHOSTHost = ^TBCMSDHOSTHost;
TBCMSDHOSTHost = record
| SDHCI Properties | |
SDHCI:TSDHCIHost;
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| BCMSDHOST Properties | |
IRQ:LongWord;
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The IRQ number for this device |
DREQ:LongWord;
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The DMA DREQ ID for this device |
Lock:TSpinHandle;
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Host lock (Differs from lock in Host portion) (Spin lock due to use by interrupt handler) |
EnableFIQ:LongBool;
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Use FIQ instead of IRQ |
GPIOFirst:LongWord;
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The starting pin number for GPIO assignments (or GPIO_PIN_UNKNOWN if externally configured) |
GPIOLast:LongWord;
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The ending pin number for GPIO assignments (or GPIO_PIN_UNKNOWN if externally configured) |
GPIOFunction:LongWord;
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The function number for GPIO assignments (or GPIO_FUNCTION_UNKNOWN if externally configured) |
ClockDivider:LongWord;
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Cached Clock Divider (CDIV) register |
HostConfiguration:LongWord;
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Cached Host Configuration (HCFG) register |
FirmwareSetsClockDivider:LongBool;
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True if the firmware controls the clock divider |
CommandQuickPollRetries:LongWord;
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NanosecondsPerFifoWord:LongWord;
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AllowDMA:LongBool;
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ResetClock:LongBool;
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Reset the clock for the next request |
MaxDelay:LongWord;
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Maximum length of time spent waiting (in Milliseconds) |
StopTime:Int64;
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When the last stop was issued (in Clock Ticks) |
DrainWords:LongWord;
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Last words of FIFO to drain on DMA read |
DrainOffset:LongWord;
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Offset for data during FIFO drain on DMA read |
UseDMA:LongBool;
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Use DMA for the current data transfer |
UseBusy:LongBool;
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Wait for busy interrupt on current command |
DelayAfterStop:LongWord;
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Minimum time between stop and subsequent data transfer (in Microseconds) |
DelayAfterThisStop:LongWord;
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Minimum time between this stop and subsequent data transfer (in Microseconds) |
UserOverclock50:LongWord;
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User's preferred frequency to use when 50MHz is requested (in MHz) |
Overclock50:LongWord;
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Frequency to use when 50MHz is requested (in MHz) |
Overclock:LongWord;
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Current frequency if overclocked, else zero (in Hz) |
PIOLimit:LongWord;
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Maximum block count for PIO (0 = always DMA / 0x7FFFFFF = always PIO) |
PIOTimeout:LongWord;
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PIO Read or Write block timeout (in milliseconds) |
DMAData:TDMAData;
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DMA data descriptor for current request (If applicable) |
DMADirection:LongWord;
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DMA data direction for current request (If applicable) |
DMABuffer:Pointer;
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DMA bounce buffer for the current request (If applicable) |
Public variables
None defined
Function declarations
Initialization functions
procedure BCMSDHOSTInit;
Description: Initialize the BCMSDHOST unit and version table
| Note | Called only during system startup |
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BCMSDHOST functions
function BCMSDHOSTCreate(Address:PtrUInt; const Name:String; IRQ,DREQ,ClockMinimum,ClockMaximum,GPIOFirst,GPIOLast,GPIOFunction:LongWord; EnableFIQ:Boolean):PSDHCIHost;
Description: Create and register a new BCMSDHOST SDHCI device which can be accessed using the SDHCI API
| Address | The address of the BCMSDHOST registers |
|---|---|
| Name | The text description of this device which will show in the device list (Optional) |
| IRQ | The interrupt number for the BCMSDHOST |
| DREQ | The DMA data request ID for the BCMSDHOST |
| ClockMinimum | The minimum frequency for the BCMSDHOST clock |
| ClockMaximum | The maximum frequency for the BCMSDHOST clock |
| GPIOFirst | The starting pin number for GPIO assignments (or GPIO_PIN_UNKNOWN if externally configured) |
| GPIOLast | The ending pin number for GPIO assignments (or GPIO_PIN_UNKNOWN if externally configured) |
| GPIOFunction | The function number for GPIO assignments (or GPIO_FUNCTION_UNKNOWN if externally configured) |
| EnableFIQ | Enable fast interrupt support for the BCMSDHOST |
| Return | Pointer to the new SDHCI device or nil if the SDHCI device could not be created |
function BCMSDHOSTDestroy(SDHCI:PSDHCIHost):LongWord;
Description: Stop, deregister and destroy a BCMSDHOST SDHCI device created by this driver
| SDHCI | The SDHCI device to destroy |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
BCMSDHOST MMC functions
function BCMSDHOSTSendCommand(MMC:PMMCDevice; Command:PMMCCommand):LongWord;
Description: Implementation of MMCDeviceSendCommand API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use MMCDeviceSendCommand instead. |
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function BCMSDHOSTSetIOS(MMC:PMMCDevice):LongWord;
Description: Implementation of MMCDeviceSetIOS API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use MMCDeviceSetIOS instead. |
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function BCMSDHOSTGetCardDetect(MMC:PMMCDevice):LongWord;
Description: Implementation of MMCDeviceGetCardDetect API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use MMCDeviceGetCardDetect instead. |
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function BCMSDHOSTGetWriteProtect(MMC:PMMCDevice):LongWord;
Description: Implementation of MMCDeviceGetWriteProtect API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use MMCDeviceGetWriteProtect instead. |
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BCMSDHOST SDHCI functions
function BCMSDHOSTHostStart(SDHCI:PSDHCIHost):LongWord;
Description: Implementation of SDHCIHostStart API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCIHostStart instead. |
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function BCMSDHOSTHostStop(SDHCI:PSDHCIHost):LongWord;
Description: Implementation of SDHCIHostStop API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCIHostStop instead. |
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function BCMSDHOSTReset(SDHCI:PSDHCIHost; Mask:Byte):LongWord;
Description: Implementation of SDHCIReset API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCIReset instead. |
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function BCMSDHOSTHardwareReset(SDHCI:PSDHCIHost):LongWord;
Description: Implementation of SDHCIHardwareReset API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCIHardwareReset instead. |
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function BCMSDHOSTSetPower(SDHCI:PSDHCIHost; Power:Word):LongWord;
Description: Implementation of SDHCISetPower API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCISetPower instead. |
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function BCMSDHOSTSetClock(SDHCI:PSDHCIHost; Clock:LongWord):LongWord;
Description: Implementation of SDHCISetClock API for BCMSDHOST SDHCI
| Note | Not intended to be called directly by applications, use SDHCISetClock instead. |
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procedure BCMSDHOSTCommandWaitWorker(SDHCI:PSDHCIHost);
Description: Worker thread task to wait for BCMSDHOST command completion
| Note | Not intended to be called directly by applications |
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procedure BCMSDHOSTDMARequestCompleted(Request:PDMARequest);
Description: DMA Request completion callback for the BCMSDHOST host controller
| Note | Not intended to be called directly by applications |
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function BCMSDHOSTSharedInterruptHandler(Number,CPUID,Flags:LongWord; SDHCI:PSDHCIHost):LongWord;
Description: Interrupt handler for the BCMSDHOST host controller
| Note | Not intended to be called directly by applications |
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BCMSDHOST helper functions
function BCMSDHOSTSetSDHostClock(var Clock,Value1,Value2:LongWord):LongWord;
Description: Set the SD Host Clock value in the Mailbox property tags channel
| Note | None documented |
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