; Copyright 2009 Castle Technology Ltd
;
; Licensed under the Apache License, Version 2.0 (the "License");
; you may not use this file except in compliance with the License.
; You may obtain a copy of the License at
;
; http://www.apache.org/licenses/LICENSE-2.0
;
; Unless required by applicable law or agreed to in writing, software
; distributed under the License is distributed on an "AS IS" BASIS,
; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
; See the License for the specific language governing permissions and
; limitations under the License.
;
GET Hdr:ListOpts
GET Hdr:Macros
GET Hdr:System
GET Hdr:Machine.<Machine>
GET Hdr:ImageSize.<ImageSize>
$GetIO
GET Hdr:OSEntries
GET Hdr:HALEntries
GET Hdr:HALDevice
GET Hdr:DMA
GET Hdr:DMADevice
GET Hdr:Proc
GET hdr.omap3530
GET hdr.StaticWS
AREA |Asm$$Code|, CODE, READONLY, PIC
EXPORT SDMA_Init
EXPORT SDMA_Had_POR
IMPORT memcpy
IMPORT DebugHALPrint
IMPORT DebugHALPrintReg
IMPORT HAL_IRQClear
IMPORT HAL_FIQClear
IMPORT HAL_CounterDelay
; Flag to enable gobs of debug output
GBLL SDMADebug
SDMADebug SETL {FALSE}
; Flag to disable IRQs during (most) debug output, making high-frequency output more readable
GBLL SDMADebugNoIRQ
SDMADebugNoIRQ SETL {FALSE} :LAND: SDMADebug
MACRO
DumpReg $ptr, $temp, $r
LCLS string
string SETS "::" :CC: "$r" :CC: ": "
LDR $temp, [$ptr, #$r]
DebugReg $temp, $string
MEND
SDMA_Had_POR
; Called pre MMU enable and pre SDMA_Init!
;
; In an ideal world we'd just read the PRM_RSTST.GLOBALCOLD_RST to
; figure out what the last reset reason was, but the BeagleBoard has
; erroneously wired the reset button to the SYS_nRESPWRON instead of
; the SYS_nRESWARM pin. This means both power on resets and pressing
; the reset button set the GLOBALCOLD_RST bit.
; So we need to find some bits that aren't cleared to known values on
; a cold reset - and there aren't many - the internal SRAM is all
; reused by the ROM bootloader.
;
; However, the SDMA does have some control bits that are implemented
; as SRAM (and hence not defined on power up), so we seed them with a
; statistically unlikely number and compare this key on startup to
; decide which reset type it is.
;
; Register DMA4_CLNK_CTRLi isn't being used and it has up to 5 bits
; per channel to play with. Use a 32 bit key spread 4 bits a piece.
MOV a1, #0
LDR a2, =L4_sDMA + DMA4_i + DMA4_CLNK_CTRLi
LDR a4, =&ABCD1234
10
; Compare 4 bits read with the key, and accumulate the result
LDR ip, [a2]
EOR a3, ip, a4
ORR a1, a1, a3, LSL #32-4
; Write 4 bits from the key while we're passing
BFI ip, a4, #0, #4
STR ip, [a2], #DMA4_CHANNEL_SIZE
MOVS a4, a4, LSR #4
BNE %BT10
MOV pc, lr
SDMA_Init
Push "v1-v4,lr"
; Do basic reset of SDMA controller, then register the HAL devices
LDR v2, L4_sDMA_Log
[ SDMADebug
DebugReg v2, "SDMA_Init, L4_sDMA_Log="
]
MOV a2, #2
STR a2, [v2, #DMA4_OCP_SYSCONFIG]
5
LDR a2, [v2, #DMA4_SYSSTATUS]
TST a2, #1
BEQ %BT5
[ SDMADebug
DebugTX "DMA reset OK"
]
; Autoidle, smart idle
LDR a2, =1+(2<<3)+(2<<12)
STR a2, [v2, #DMA4_OCP_SYSCONFIG]
ADR v1, SDMAWS
MOV a1, v1
ADR a2, ControllerTemplate
MOV a3, #SDMAC_DeviceSize
BL memcpy
STR sb, [v1, #:INDEX:SDMACWorkspace]
STR v2, [v1, #:INDEX:SDMACRegs]
LDR a2, =SDMAC_DeviceSize+(SDMA_NumDevices-1)*SDMA_DeviceSize
ADD a2, a2, v1
ADD a3, v1, #(:INDEX:SDMACPhysList)+SDMA_NumDevices*4
MOV a4, #SDMA_NumDevices
10
SUBS a4, a4, #1
STRPL a2, [a3, #-4]!
SUBPL a2, a2, #SDMA_DeviceSize
BPL %BT10
; This is a bit nasty. We register the DMA controller before we initialise the channels.
MOV a2, v1
MOV a1, #0
CallOS OS_AddDevice
ADR v1, SDMAWS + SDMAC_DeviceSize
MOV v2, #0
LDR v3, L4_sDMA_Log
ADD v4, v3, #DMA4_i
10
[ SDMADebug
DebugReg v2, "Set up device "
]
MOV a1, v1
ADR a2, ChannelTemplate
MOV a3, #SDMA_DeviceSize
BL memcpy
STR v3, SDMARegs
MOV a4, #1
STR v4, SDMAChanRegs
MOV a4, a4, LSL v2
STR sb, SDMAWorkspace
STR a4, SDMAIRQMask
ADR a3, SDMAWS
STR a3, [a1, #HALDevice_DMAController]
ADD a2, a1, #:INDEX:SDMADesc
STR a2, [a1, #HALDevice_Description]
; Simple two digit number -> string conversion
MOV a3, #48 ; '0'
MOV a4, v2
15
CMP a4, #10
ADDGE a3, a3, #1
SUBGE a4, a4, #10
BGE %BT15
ADD a2, a2, #ChannelDescNum-ChannelDescStart
CMP a3, #48
STRNEB a3, [a2], #1
ADD a4, a4, #48
STRB a4, [a2]
MOV a2, a1
MOV a1, #0
CallOS OS_AddDevice
ADD v1, v1, #SDMA_DeviceSize
ADD v2, v2, #1
ADD v4, v4, #DMA4_CHANNEL_SIZE
CMP v2, #SDMA_NumDevices
BLT %BT10
[ SDMADebug
DebugTX "SDMA_Init done"
]
Pull "v1-v4,pc"
LTORG
; DMA controller HAL device
ControllerTemplate
DCW HALDeviceType_SysPeri + HALDeviceSysPeri_DMAC
DCW HALDeviceID_DMAC_OMAP3
DCD HALDeviceBus_Sys + HALDeviceSysBus_SonicsMX
DCD &10000 ; API version - 1.0
DCD SDMACDesc
DCD 0 ; Address - N/A
% 12 ; Reserved
DCD SDMACActivate
DCD SDMACDeactivate
DCD SDMACReset
DCD SDMACSleep
DCD SDMA_IRQ_0 ; Device. Bit 31 not set, because DMAManager should either use the controller to determine the interrupt cause, or the channels, but not both.
DCD 0 ; TestIRQ cannot be called
% 8
DCD SDMACFeatures
DCD SDMACEnumerate
DCD SDMACAllocate
DCD SDMACDeallocate
DCD SDMACTestIRQ2
ASSERT (.-ControllerTemplate) = HALDevice_DMAC_Size_0_1
% 4 ; Regs
% 4 ; HAL Workspace
% 4 ; Mask of allocated devices
% 4 * SDMA_NumDevices ; Device list
ALIGN
ASSERT (.-ControllerTemplate) = SDMAC_DeviceSize
; DMA 'physical' channel HAL device
ChannelTemplate
; Public interface
DCW HALDeviceType_SysPeri + HALDeviceSysPeri_DMAB
DCW HALDeviceID_DMAB_OMAP3
DCD HALDeviceBus_Sys + HALDeviceSysBus_SonicsMX
DCD &10000 ; API version - 1.0
DCD 0 ; Description
DCD 0 ; Address - N/A
% 12 ; Reserved
DCD SDMAActivate
DCD SDMADeactivate
DCD SDMAReset
DCD SDMASleep
DCD SDMA_IRQ_0+(1<<31) ; Device. Bit 31 set because it's shared with all the channels.
DCD SDMATestIRQ
% 8
DCD SDMAFeatures
DCD 0 ; DMA controller device
DCD SDMAAbort
DCD SDMASetOptions
DCD SDMASetCurrentTransfer
DCD SDMASetNextTransfer
DCD SDMATransferState
DCD SDMAIRQClear
DCD SDMAStatus
DCD SDMASetCurrentTransfer2
DCD SDMASetNextTransfer2
DCD SDMATransferState2
ASSERT (.-ChannelTemplate) = HALDevice_DMA_Size
; Private interface
DCD 0 ; Regs (for the controller)
DCD 0 ; Regs (for this channel)
DCD 0 ; HAL Workspace
DCD 0 ; IRQ mask
DCD 0 ; Packet size ptr
ChannelDescStart
= "OMAP3 system DMA channel "
ChannelDescNum
DCB 0, 0, 0 ; 2 digit number + terminator
ALIGN
ASSERT (.-ChannelDescStart) = 28 ; hardcoded in hdr.SDMA!
ASSERT (.-ChannelTemplate) = SDMA_DeviceSize
SDMACDesc
= "OMAP3 system DMA controller", 0
ALIGN
; DMA controller device
; ---------------------
SDMACActivate
; Nothing to do?
MOV a1, #1
MOV pc, lr
SDMACDeactivate
; Just do the same as on a reset...
SDMACReset
Entry "sb"
LDR sb, SDMACWorkspace
LDR a3, SDMACRegs
MOV a2, #2
STR a2, [a3, #DMA4_OCP_SYSCONFIG]
5
LDR a2, [a3, #DMA4_SYSSTATUS]
TST a2, #1
BEQ %BT5
; Set DMA4_GCR to a sensible value:
LDR a2, =&100080 ; Arbitration rate=1, no reserved resources, max per-channel FIFO depth 128 bytes
STR a2, [a3, #DMA4_GCR]
; Reset the allocation list
MOV a2, #0
STR a2, SDMACAllocated
; Give INTC a bit of a kick, since any pending IRQs will no longer look like they came from us, causing DMAManager to fail to clear them
MOV a1, #SDMA_IRQ_0 ; Only need to clear the first IRQ since all we're interested in is the write to INTCPS_CONTROL
BL HAL_IRQClear
MOV a1, #SDMA_IRQ_0
BL HAL_FIQClear ; Just in case
EXIT
SDMACSleep
; Nothing we can do
MOV a1, #0
MOV pc, lr
SDMACFeatures
MOV a1, #0
MOV pc, lr
SDMACEnumerate
ADR a1, SDMACPhysList
MOV a2, #SDMA_NumDevices
MOV pc, lr
SDMACAllocate
; a2 = RISC OS-speak logical DMA channel
; In OMAP speak, this is the value to be programmed into the DMA4_CCRi register, i.e. 0 for CPU synchronisation, else the DMA request ID + 1
; For the moment, we assume the user is smart enough not to request the same logical ID multiple times, because that will result in bad things (unless they're chained together)
; This allocation scheme also means we're technically limited to using 1 CPU synchronised channel at once :(
Entry "sb"
LDR sb, SDMACWorkspace
[ SDMADebug
DebugReg a2, "SDMACAllocate: "
]
MRS lr, CPSR
ORR a4, lr, #I32_bit
MSR CPSR_c, a4 ; interrupts off
LDR a3, SDMACAllocated
CLZ a4, a3
CMP a4, #32-SDMA_NumDevices ; Assume that channels 0 to SDMA_NumDevices are to be used
MOVEQ a1, #0 ; No controllers left
BEQ %FT10
MOV ip, #1
ORR a3, a3, ip, ROR a4
STR a3, SDMACAllocated
; Grab the pointer to the DMA channel device
ADR a1, SDMACPhysList
RSB a4, a4, #32
LDR a1, [a1, a4, LSL #2]
; Set the packet size pointer, if appropriate
CMP a2, #McBSP2_DMA_TX+1
ADREQ a3, DMAPktSz_Audio
MOVNE a3, #0
STR a3, SDMAPacketSizePtr
; Program the request ID into the channel registers
LDR a3, SDMARegs
AND ip, a2, #&1F
AND a2, a2, #&60
ORR ip, ip, a2, LSL #14
STR ip, [a3, #DMA4_i+DMA4_CCRi]
10
MSR CPSR_c, lr ; Interrupts restored
[ SDMADebug
DebugReg a4, "<-Channel: "
DebugReg a1, "<-Device: "
]
EXIT
SDMACDeallocate
; For API 0.x, we only get given the logical channel #. Which is bad, because memory-to-memory transfers all use logical channel 0, so there could easily be multiple instances of the same logical channel.
; So for API 1.x, we also get passed a pointer to the channel which we're deallocating (in a3)
[ SDMADebug
Entry "sb"
LDR sb, SDMACWorkspace
DebugReg a2, "SDMACDeallocate: "
DebugReg a3, " Ptr: "
]
; Assuming a3 is valid, we can just load the IRQ mask word and use that to update our allocation mask
MRS ip, CPSR
LDR a3, [a3, #:INDEX:SDMAIRQMask]
ORR a4, ip, #I32_bit
MSR CPSR_c, a4 ; interrupts off
LDR a2, SDMACAllocated
BIC a2, a2, a3
STR a2, SDMACAllocated
MSR CPSR_c, ip ; Interrupts restored
[ SDMADebug
CLZ a1, a3
RSB a1, a1, #31
DebugReg a1, " Was channel #"
EXIT
|
MOV pc, lr
]
SDMACTestIRQ2
; Return index of interrupting channel (as per Enumerate list), or -1 for none
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMACWorkspace
DebugTX "SDMACTestIRQ2:"
]
LDR a2, SDMACRegs
LDR a2, [a2, #DMA4_IRQSTATUS_L0]
CLZ a1, a2
RSB a1, a1, #31 ; Device index or -1 for none
[ SDMADebug
DebugReg a1, "="
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
; DMA channel device
; ------------------
SDMAActivate
; The only thing we do here is enable the IRQ for the device
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMAActivate: "
]
LDR a2, SDMARegs
MRS a3, CPSR
LDR ip, SDMAIRQMask
ORR a4, a3, #I32_bit
MSR CPSR_c, a4 ; interrupts off
LDR a4, [a2, #DMA4_IRQENABLE_L0]
ORR a4, a4, ip
STR a4, [a2, #DMA4_IRQENABLE_L0] ; Unmask the interrupt
MOV a1, #1
MSR CPSR_c, a3 ; Interrupts restored
[ SDMADebug
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMAAbort ; Docs say Abort musn't block, but Deactivate shouldn't result in a significant block so we'll just use that
SDMADeactivate
Entry "v1,sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
[ SDMADebug
DebugReg a1, "SDMAAbort/Deactivate: "
]
; Halt any active transfer
LDR a2, SDMAChanRegs
LDR a3, [a2, #DMA4_CCRi]
BIC a3, a3, #1<<7 ; Clear ENABLE bit
STR a3, [a2, #DMA4_CCRi]
10
LDR a3, [a2, #DMA4_CCRi]
TST a3, #(1<<9) :OR: (1<<10) ; Check RD_ACTIVE & WR_ACTIVE
BNE %BT10
; Now disable interrupts (or should we do this first?)
LDR a2, SDMARegs
MRS v1, CPSR
LDR ip, SDMAIRQMask
ORR a4, v1, #I32_bit
MSR CPSR_c, a4 ; Interrupts off
LDR a1, [a2, #DMA4_IRQSTATUS_L0]
LDR a4, [a2, #DMA4_IRQENABLE_L0]
TST a1, ip
BIC a4, a4, ip
STR a4, [a2, #DMA4_IRQENABLE_L0] ; Mask the interrupt
; If the channel was interrupting, we must call HAL_IRQClear to (potentially) restart interrupt processing
; todo - this code should probably be in the OS, like all the other code that's meant to call HAL_IRQClear
MOVNE a1, #SDMA_IRQ_0
BLNE HAL_IRQClear
MSR CPSR_c, v1 ; Interrupts restored
; Done!
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
SDMAReset
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMAReset: "
]
LDR a2, SDMARegs
MRS a3, CPSR
LDR ip, SDMAIRQMask
ORR a4, a3, #I32_bit
MSR CPSR_c, a4 ; Interrupts off
LDR a4, [a2, #DMA4_IRQENABLE_L0]
BIC a4, a4, ip
STR a4, [a2, #DMA4_IRQENABLE_L0] ; Mask the interrupt
MSR CPSR_c, a3 ; Interrupts restored
; Now reset the channel registers to something sensible
MOV ip, #&1F
LDR a2, SDMAChanRegs
ORR ip, ip, #3<<19
LDR a3, [a2, #DMA4_CCRi]
MOV a1, #0
AND a3, a3, ip ; Mask everything except the SYNCHRO_CONTROL field
STR a3, [a2, #DMA4_CCRi]
10
LDR a3, [a2, #DMA4_CCRi]
TST a3, #(1<<9) :OR: (1<<10) ; Check RD_ACTIVE & WR_ACTIVE
BNE %BT10
LDR a4, [a2, #DMA4_CLNK_CTRLi]
BIC a4, a4, #&8000 ; Disable channel linking
STR a4, [a2, #DMA4_CLNK_CTRLi]
MVN a4, #0
STR a1, [a2, #DMA4_CICRi] ; Disable all interrupts
STR a4, [a2, #DMA4_CSRi] ; Reset interrupt status bits
; These registers don't really need to be reset, because we'll reprogram them as and when needed.
; STR a1, [a2, #DMA4_CSDPi]
; STR a1, [a2, #DMA4_CENi]
; STR a1, [a2, #DMA4_CFNi]
; STR a1, [a2, #DMA4_CSSAi]
; STR a1, [a2, #DMA4_CDSAi]
; STR a1, [a2, #DMA4_CSEIi]
; STR a1, [a2, #DMA4_CSFIi]
; STR a1, [a2, #DMA4_CDEIi]
; STR a1, [a2, #DMA4_CDFIi]
; STR a1, [a2, #DMA4_CDACi]
; STR a1, [a2, #DMA4_COLORi]
; These registers are readonly and thus can't be reset
; STR a1, [a2, #DMA4_CSACi]
; STR a1, [a2, #DMA4_CCENi]
; STR a1, [a2, #DMA4_CCFNi]
; Finished!
[ SDMADebug
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMASleep
; Nothing we can do
MOV a1, #0
MOV pc, lr
SDMATestIRQ
; This interface doesn't work too well, due to there being many more interrupt channels than IRQ lines. Hence the addition of TestIRQ2 to the controller device.
; This old interface is retained purely for backwards-compatability
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMATestIRQ: "
]
LDR a2, SDMARegs
LDR a3, SDMAIRQMask
LDR a4, [a2, #DMA4_IRQSTATUS_L0]
ANDS a1, a4, a3
MOVNE a1, #1 ; 1 = interrupting, 0 = not interrupting
[ SDMADebug
DebugReg a1, "<-"
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMAFeatures
; Check SYNCHRO_CONTROL field to see if this is CPU synchronised (memory-to-memory) or device synchronised
LDR a2, SDMAChanRegs
MOV a3, #&1F
LDR a2, [a2, #DMA4_CCRi]
ORR a3, a3, #3<<19
TST a2, a3
MOVEQ a1, #DMAFeaturesFlag_DualAddress+DMAFeaturesFlag_NoInitIRQ
MOVNE a1, #DMAFeaturesFlag_NoInitIRQ
MOV pc, lr
SDMASetOptions
; a2: bit 0: 1=memory->device, 0=device->memory (iff device DMA)
; bits 1-5: transfer unit width, bytes
; bits 6-8: cycle speed, ignored
; bits 9-12: minimum delay between transfers on same physical channel, ignored
; bit 13: 1=disable burst transactions
; bit 14: 1=bypass clock synchronisation, ignored
; a3: device address for device DMA
; We use this call to program everything except the transfer source/dest address (and the transfer length)
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMASetOptions: "
DebugReg a2, "->Flags: "
DebugReg a3, "->Addr: "
|
Entry
]
LDR a4, SDMAChanRegs
MOV lr, #&1F
; Calculate CCR
LDR ip, [a4, #DMA4_CCRi]
ORR lr, lr, #3<<19
ANDS ip, ip, lr ; Clear everything except the SYNCHRO bits
; SYNCHRO_CONTROL == 0 -> is memory-to-memory channel
ORREQ ip, ip, #(1<<14)+(1<<12) ; Post-increment src & dest
ORREQ ip, ip, #(1<<24) ; Source-synchronised for mem-to-mem
BEQ %FT10
; Else this is some kind of device channel. Program appropriately.
TST a2, #DMASetOptionsFlag_Write
ORREQ ip, ip, #1<<14 ; Post-increment dest for device->memory
STREQ a3, [a4, #DMA4_CSSAi] ; Source addr = Device address
ORRNE ip, ip, #1<<12 ; Post-increment src for memory->device
STRNE a3, [a4, #DMA4_CDSAi] ; Dest addr = Device address
ORRNE ip, ip, #1<<23 ; Enable prefetch for mem->device only
; Configure for packet transfers if required
LDR a3, SDMAPacketSizePtr
CMP a3, #0
ORRNE ip, ip, #1<<5 ; FS +
ORRNE ip, ip, #1<<18 ; BS = packet transfer
10
STR ip, [a4, #DMA4_CCRi]
; Calculate CSDP
AND a3, a2, #DMASetOptionsMask_Width ; Get transfer unit size
CMP a3, #2:SHL:DMASetOptionsShift_Width
MOVGT a3, #(1<<6)+2 ; 32bit or larger data (plus set SRC_PACKED)
MOVEQ a3, #(1<<6)+1 ; 16bit data
MOVLT a3, #(1<<6)+0 ; 8bit data
ORR a3, a3, #(1<<13)+(2<<16) ; DST_PACKED, last write nonposted
TST a2, #DMASetOptionsFlag_NoBursts
ORREQ a3, a3, #3<<7 ; Source burst of 64 bytes
ORREQ a3, a3, #3<<14 ; Dest burst of 64 bytes
TST ip, lr
BEQ %FT20
; If it's a device transfer, disable packing for the device side
TST a2, #DMASetOptionsFlag_Write
BICEQ a3, a3, #(1<<6) ; Disable src packing for device->memory
BICNE a3, a3, #(1<<13) ; Disable dest packing for memory->device
20
STR a3, [a4, #DMA4_CSDPi]
; Enable frame interrupt - this should trigger when the transfer completes (since it only contains one frame)
MOV a1, #1<<3
STR a1, [a4, #DMA4_CICRi]
; Done
[ SDMADebug
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
]
EXIT
SDMASetCurrentTransfer
; a2: buffer physical address
; a3: buffer length, bytes
; a4: bit 0: 1="stop and raise TC signal when this transfer completes". Ignore?
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMASetCurrentTransfer: "
DebugReg a2, "->Buffer: "
DebugReg a3, "->Length: "
|
Entry
]
LDR a4, SDMAChanRegs
LDR ip, [a4, #DMA4_CCRi]
TST ip, #1<<12
LDR lr, [a4, #DMA4_CSDPi]
STREQ a2, [a4, #DMA4_CDSAi] ; device->memory, so set dest addr
AND lr, lr, #3 ; Get element size
STRNE a2, [a4, #DMA4_CSSAi] ; memory->device, so set src addr
MOV a3, a3, LSR lr ; Get number of elements in buffer
STR a3, [a4, #DMA4_CENi] ; todo - what to do if we're asked to transfer too much data?
MOV a2, #1
STR a2, [a4, #DMA4_CFNi] ; Only 1 frame to transfer
; Check if this is a packet transfer, and program appropriately
LDR a2, SDMAPacketSizePtr
CMP a2, #0
BEQ %FT10
LDR a2, [a2]
TST ip, #1<<12
STREQ a2, [a4, #DMA4_CSFIi] ; device->memory, put it here
STRNE a2, [a4, #DMA4_CDFIi] ; memory->device, put it here
10
; Now just enable it?
ORR ip, ip, #(1<<7)+(1<<5) ; Frame synchronised by default if not packet synchronised
[ SDMADebug
DebugReg ip, "::DMA4_CCRi: "
DumpReg a4, a1, DMA4_CLNK_CTRLi
DumpReg a4, a1, DMA4_CICRi
DumpReg a4, a1, DMA4_CSRi
DumpReg a4, a1, DMA4_CSDPi
DumpReg a4, a1, DMA4_CENi
DumpReg a4, a1, DMA4_CFNi
DumpReg a4, a1, DMA4_CSSAi
DumpReg a4, a1, DMA4_CDSAi
DumpReg a4, a1, DMA4_CSEIi
DumpReg a4, a1, DMA4_CSFIi
DumpReg a4, a1, DMA4_CDEIi
DumpReg a4, a1, DMA4_CDFIi
DumpReg a4, a1, DMA4_CSACi
DumpReg a4, a1, DMA4_CDACi
DumpReg a4, a1, DMA4_CCENi
DumpReg a4, a1, DMA4_CCFNi
DumpReg a4, a1, DMA4_COLORi
]
STR ip, [a4, #DMA4_CCRi]
[ SDMADebug
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
]
EXIT
SDMASetNextTransfer
; N/A
MOV pc, lr
SDMATransferState
; We need to return the current read/write address, and the amount left to transfer... I think
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMATransferState: "
]
MRS ip, CPSR
LDR a3, SDMAChanRegs
ORR a4, ip, #I32_bit
MSR CPSR_c, a4 ; Interrupts off
[ SDMADebug
DumpReg a3, a2, DMA4_CCRi
DumpReg a3, a2, DMA4_CLNK_CTRLi
DumpReg a3, a2, DMA4_CICRi
DumpReg a3, a2, DMA4_CSRi
DumpReg a3, a2, DMA4_CSDPi
DumpReg a3, a2, DMA4_CENi
DumpReg a3, a2, DMA4_CFNi
DumpReg a3, a2, DMA4_CSSAi
DumpReg a3, a2, DMA4_CDSAi
DumpReg a3, a2, DMA4_CSEIi
DumpReg a3, a2, DMA4_CSFIi
DumpReg a3, a2, DMA4_CDEIi
DumpReg a3, a2, DMA4_CDFIi
DumpReg a3, a2, DMA4_CSACi
DumpReg a3, a2, DMA4_CDACi
DumpReg a3, a2, DMA4_CCENi
DumpReg a3, a2, DMA4_CCFNi
DumpReg a3, a2, DMA4_COLORi
]
LDR a1, [a3, #DMA4_CCRi]
LDR a2, [a3, #DMA4_CCENi] ; Get current element number
LDR a4, [a3, #DMA4_CENi] ; Transfer length
TST a1, #1<<12
LDR a1, [a3, #DMA4_CSDPi]
LDREQ a3, [a3, #DMA4_CDSAi] ; Get correct source address
AND a1, a1, #3 ; Get element size
LDRNE a3, [a3, #DMA4_CSSAi]
MOV a2, a2, LSL a1
MOV a4, a4, LSL a1
ADD a1, a3, a2 ; Update source address
SUB a2, a4, a2 ; Update transfer length
MSR CPSR_c, ip ; Interrupts restored
[ SDMADebug
DebugReg a1, "<-Addr: "
DebugReg a2, "<-Length: "
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMAIRQClear
Entry "v1,sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
[ SDMADebug
DebugReg a1, "SDMAIRQClear: "
]
MRS v1, CPSR
LDR ip, SDMAChanRegs
ORR a4, v1, #I32_bit
LDR a2, SDMARegs
MVN a3, #0
LDR a1, SDMAIRQMask
MSR CPSR_c, a4 ; Interrupts off
STR a3, [ip, #DMA4_CSRi] ; Clear all active interrupts
STR a1, [a2, #DMA4_IRQSTATUS_L0] ; Clear main IRQ bit
MOV a1, #SDMA_IRQ_0
BL HAL_IRQClear ; Clear IRQ (todo - should be in DMAManager?)
MSR CPSR_c, v1 ; Interrupts restored
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
SDMAStatus
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMAStatus: "
]
LDR a2, SDMAChanRegs
MOV a1, #DMAStatusFlag_NoUnstarted ; We don't support double-buffering, so NoUnstarted must always be set
LDR a2, [a2, #DMA4_CCRi]
TST a2, #1<<7 ; Check ENABLE bit
ORREQ a1, a1, #DMAStatusFlag_Overrun ; If we're inactive, we're in the overrun state
[ SDMADebug
DebugReg a1, "<-Flags: "
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMASetCurrentTransfer2
; a2: source physical address
; a3: dest physical address
; a4: buffer length, bytes
; a5: bit 0: 1="stop and raise TC signal when this transfer completes". Ignore?
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMASetCurrentTransfer2: "
DebugReg a2, "->Source: "
DebugReg a3, "->Dest: "
DebugReg a4, "->Length: "
]
LDR ip, SDMAChanRegs
LDR a1, [ip, #DMA4_CSDPi]
STR a2, [ip, #DMA4_CSSAi] ; set src addr
AND a1, a1, #3 ; Get element size
STR a3, [ip, #DMA4_CDSAi] ; set dest addr
MOV a4, a4, LSR a1 ; Get number of elements in buffer
STR a4, [ip, #DMA4_CENi] ; todo - what to do if we're asked to transfer too much data?
MOV a2, #1
STR a2, [ip, #DMA4_CFNi] ; Only 1 frame to transfer
; Now just enable it?
ORR a1, a1, #1<<7
STR a1, [ip, #DMA4_CCRi]
[ SDMADebug
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
SDMASetNextTransfer2
; N/A
MOV pc, lr
SDMATransferState2
; We need to return the current read & write address, and the amount left to transfer... I think
[ SDMADebug
Entry "sb"
[ SDMADebugNoIRQ
PHPSEI lr,sb
Push "lr"
]
LDR sb, SDMAWorkspace
DebugReg a1, "SDMATransferState2: "
]
MRS ip, CPSR
LDR a2, SDMAChanRegs
ORR a4, ip, #I32_bit
MSR CPSR_c, a4 ; Interrupts off
LDR a1, [a2, #DMA4_CSDPi]
LDR a3, [a2, #DMA4_CCENi] ; Get current element number
AND a1, a1, #3 ; Get element size
LDR a4, [a2, #DMA4_CENi] ; Transfer length
MOV a3, a3, LSL a1
MOV a4, a4, LSL a1
LDR a1, [a2, #DMA4_CSSAi]
LDR a2, [a2, #DMA4_CDSAi]
ADD a1, a1, a3 ; Update source address
ADD a2, a2, a3 ; Update dest address
SUB a3, a4, a3 ; Update transfer length
MSR CPSR_c, ip ; Interrupts restored
[ SDMADebug
DebugReg a1, "<-Source: "
DebugReg a2, "<-Dest: "
DebugReg a3, "<-Length: "
[ SDMADebugNoIRQ
Pull "lr"
PLP lr
]
EXIT
|
MOV pc, lr
]
LTORG
END