53 lines
1.2 KiB
Go
53 lines
1.2 KiB
Go
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package ram
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import (
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"errors"
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"fmt"
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"git.elyanpoujol.fr/elyan/central-arch/pkg/events"
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"git.elyanpoujol.fr/elyan/central-arch/pkg/simcontext"
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"git.elyanpoujol.fr/elyan/central-arch/pkg/simstate"
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"git.elyanpoujol.fr/elyan/central-arch/pkg/simstep"
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)
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type RAM struct {
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state simstate.RamState
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stepper simstep.SimStepper
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eventLogger events.EventLogger
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}
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const alignment = 4
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func New(context simcontext.SimContext, bytes uint) (*RAM, error) {
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if bytes < alignment {
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return nil, errors.New("memory size should be at least 4 bytes")
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}
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return &RAM{
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state: simstate.RamState{Data: make([]uint32, bytes/alignment)},
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stepper: context.Stepper,
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eventLogger: context.EventLogger,
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}, nil
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}
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func (r *RAM) Read(addr uint32) (uint32, error) {
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if addr%alignment != 0 {
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return 0, fmt.Errorf("unaligned memory address: %08x", addr)
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}
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return r.state.Data[addr/alignment], nil
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}
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func (r *RAM) Write(addr uint32, value uint32) error {
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if addr%alignment != 0 {
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return fmt.Errorf("unaligned memory address: %08x", addr)
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}
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r.state.Data[addr/alignment] = value
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return nil
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}
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func (m *RAM) Fetch(addr uint32) (uint32, error) {
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return m.Read(addr)
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}
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