From bbef9f93daeb6a3565c4c28572d73130dfb6ac85 Mon Sep 17 00:00:00 2001 From: patacongo Date: Tue, 18 Dec 2012 16:15:27 +0000 Subject: Restructre address environment interfaces in preparation for incorporation into binfmt/ logic git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5442 42af7a65-404d-4744-a932-0658087f49c3 --- nuttx/arch/z80/include/z180/arch.h | 23 ++++ nuttx/arch/z80/src/z180/z180_mmu.c | 253 +++++++++++++++++++++++++++---------- 2 files changed, 208 insertions(+), 68 deletions(-) (limited to 'nuttx/arch') diff --git a/nuttx/arch/z80/include/z180/arch.h b/nuttx/arch/z80/include/z180/arch.h index 9e2197522..d7cf82a26 100644 --- a/nuttx/arch/z80/include/z180/arch.h +++ b/nuttx/arch/z80/include/z180/arch.h @@ -45,6 +45,12 @@ * Included Files ****************************************************************************/ +#include + +#include + +#include + /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ @@ -52,6 +58,23 @@ /**************************************************************************** * Public Types ****************************************************************************/ +/* The z180 address environment is represented in hardware as the 8-bit + * Common Base Register (CBR). CBR specifies the base address (on 4KB + * boundaries) used to generate a 20-bit physical address for Common Area 1 + * accesses. CBR is the upper 8-bits of the 20-bit address; the lower 14-bits + * of the base address are implicitly zero (hence the 4KB boundary alignment). + */ + +#ifdef CONFIG_ADDRENV +typedef uint8_t hw_addrenv_t; + +/* At the task-level, the z180 address environment is represented as struct + * z180_cbr_s which is defined in irq.h. + */ + +struct z180_cbr_s; +typedef FAR struct z180_cbr_s *task_addrenv_t; +#endif /**************************************************************************** * Public Variables diff --git a/nuttx/arch/z80/src/z180/z180_mmu.c b/nuttx/arch/z80/src/z180/z180_mmu.c index e24b22b8e..5f9b26be2 100644 --- a/nuttx/arch/z80/src/z180/z180_mmu.c +++ b/nuttx/arch/z80/src/z180/z180_mmu.c @@ -79,7 +79,7 @@ static struct z180_cbr_s g_cbrs[CONFIG_MAX_TASKS]; ****************************************************************************/ /**************************************************************************** - * Name: z180_mmu_findcbr + * Name: z180_mmu_alloccbr * * Description: * Find an unused struture in g_cbrs (i.e., one with reference count == 0). @@ -88,7 +88,7 @@ static struct z180_cbr_s g_cbrs[CONFIG_MAX_TASKS]; * ****************************************************************************/ -static FAR struct z180_cbr_s *z180_mmu_findcbr(void) +static inline FAR struct z180_cbr_s *z180_mmu_alloccbr(void) { int i; @@ -176,25 +176,54 @@ return g_physhandle ? OK : -ENOMEM; #endif } +/**************************************************************************** + * Address Environment Interfaces + * + * Low-level interfaces used in binfmt/ to instantiate tasks with address + * environments. These interfaces all operate on task_addrenv_t which is an + * abstract representation of the address environment and must be provided + * by arch/arch.h is CONFIG_ADDRENV is defined. + * + * up_addrenv_create - Create an address environment + * up_addrenv_vaddr - Returns the virtual base address of the address + * environment + * up_addrenv_select - Instantiate an address environment + * up_addrenv_destroy - Destroy an address environment. + * up_addrenv_assign - Assign an address environment to a TCB + * + * Higher-level interfaces used by the tasking logic. These interfaces are + * used by the functions in sched/ and all operate on the TCB which as been + * assigned an address environment by up_addrenv_assign(). + * + * up_addrenv_share - Clone the address environment assigned to one TCB + * to another. This operation is done when a pthread + * is created that share's the same address + * environment. + * up_addrenv_release - Release the TCBs reference to an address + * environment when a task/thread exists. + * + ****************************************************************************/ /**************************************************************************** * Name: up_addrenv_create * * Description: * This function is called from the binary loader logic when a new - * task is created in RAM in order to instantiate an address environment for - * the task. + * task is created in order to instantiate an address environment for the + * task. up_addrenv_create is essentially the allocator of the physical + * memory for the new task. * * Input Parameters: - * tcb - The TCB of the task needing the address environment. * envsize - The size (in bytes) of the address environment needed by the * task. + * addrenv - The location to return the representation of the task address + * environment. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ -int up_addrenv_create(FAR _TCB *tcb, size_t envsize) +int up_addrenv_create(size_t envsize, FAR task_addrenv_t *addrenv) { FAR struct z180_cbr_s *cbr; irqstate_t flags; @@ -202,10 +231,6 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize) unsigned int npages; int ret; - /* Make sure that there is no address environment in place on this TCB */ - - DEBUGASSERT(tcb->xcp.cbr == NULL); - /* Convert the size from bytes to numbers of pages */ npages = PHYS_ALIGNUP(envsize); @@ -225,7 +250,7 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize) */ flags = irqsave(); - cbr = z180_mmu_findcbr(); + cbr = z180_mmu_alloccbr(); if (!cbr) { sdbg("ERROR: No free CBR structures\n"); @@ -235,7 +260,6 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize) /* Now allocate the physical memory to back up the address environment */ - #ifdef CONFIG_GRAN_SINGLE alloc = (uintptr_t)gran_alloc(npages); #else @@ -254,9 +278,9 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize) DEBUGASSERT(alloc <= 0xff); - cbr->cbr = alloc; - cbr->pages = npages; - tcb->xcp.cbr = cbr; + cbr->cbr = (uint8_t)alloc; + cbr->pages = (uint8_t)npages; + *addrenv = (task_addrenv_t)cbr; irqrestore(flags); return OK; @@ -270,111 +294,204 @@ errout_with_irq: } /**************************************************************************** - * Name: up_addrenv_share + * Name: up_addrenv_vaddr * * Description: - * This function is called from the core scheduler logic when a thread - * is created that needs to share the address ennvironment of its parent - * task. In this case, the parent's address environment needs to be - * "cloned" for the child. + * Return the virtual address associated with the newly create address + * environment. This function is used by the binary loaders in order + * get an address that can be used to initialize the new task.. * * Input Parameters: - * ptcb - The TCB of the parent task that has the address environment. - * ctcb - The TCB of the child thread needing the address environment. + * addrenv - The representation of the task address environment previously + * returned by up_addrenv_create. + * vaddr - The location to return the virtual address. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ -int up_addrenv_share(FAR const _TCB *ptcb, FAR _TCB *ctcb) +int up_addrenv_vaddr(FAR task_addrenv_t addrenv, FAR void **vaddr) +{ + return CONFIG_Z180_COMMON1AREA_VIRTBASE; +} + +/**************************************************************************** + * Name: up_addrenv_select + * + * Description: + * After an address environment has been established for a task (via + * up_addrenv_create()), this function may be called to to instantiate + * that address environment in the virtual address space. This might be + * necessary, for example, to load the code for the task from a file or + * to access address environment private data. + * + * Input Parameters: + * addrenv - The representation of the task address environment previously + * returned by up_addrenv_create. + * oldenv + * The address environment that was in place before up_addrenv_select(). + * This may be used with up_addrenv_restore() to restore the original + * address environment that was in place before up_addrenv_select() was + * called. Note that this may be a task agnostic, hardware + * representation that is different from task_addrenv_t. + * + * Returned Value: + * Zero (OK) on success; a negated errno value on failure. + * + ****************************************************************************/ + +int up_addrenv_select(task_addrenv_t addrenv, hw_addrenv_t *oldenv) { + FAR struct z180_cbr_s *cbr = (FAR struct z180_cbr_s *)addrenv; irqstate_t flags; - /* Make sure that the child has no address environment. It is okay if - * if the parent does not have one. - */ + DEBUGASSERT(cbr && oldenv); - DEBUGASSERT(ctcb->xcp.cbr == NULL); + /* Return the current CBR value from the CBR register */ flags = irqsave(); - if (ptcb->xcp.cbr) - { - /* Clone the CBR by incrementing the reference counting and saving a - * copy in the child thread's TCB. - */ + *oldenv = (hw_addrenv_t)inp(Z180_MMU_CBR); - ptcb->xcp.cbr->crefs++; - ctcb->xcp.cbr = ptcb->xcp.cbr; - } + /* Write the new CBR value into CBR register */ + outp(Z180_MMU_CBR, cbr->cbr); irqrestore(flags); return OK; } /**************************************************************************** - * Name: up_addrenv_instantiate + * Name: up_addrenv_restore * * Description: - * After an address environment has been established for a task (via - * up_addrenv_create(). This function may be called to to instantiate - * that address environment in the virtual address space. this might be - * necessary, for example, to load the code for the task from a file or - * to access address environment private data. + * After an address environment has been temporarilty instantiated by + * up_addrenv_select, this function may be called to to restore the + * original address environment. * * Input Parameters: - * tcb - The TCB of the task or thread whose the address environment will - * be instantiated. + * oldenv - The hardware representation of the address environment + * previously returned by up_addrenv_select. * * Returned Value: - * A handle that may be used with up_addrenv_restore() to restore the - * address environment before up_addrenv_instantiate() was called. + * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ -FAR void *up_addrenv_instantiate(FAR _TCB *tcb) +int up_addrenv_restore(hw_addrenv_t oldenv) { - uint8_t oldcbr; - irqstate_t flags; + outp(Z180_MMU_CBR, (uint8_t)oldenv); + return OK; +} - /* Get the current CBR value from the CBR register */ +/**************************************************************************** + * Name: up_addrenv_destroy + * + * Description: + * Called from the binary loader loader during error handling to destroy + * the address environment previously created by up_addrenv_create(). + * + * Input Parameters: + * addrenv - The representation of the task address environment previously + * returned by up_addrenv_create. + * + * Returned Value: + * Zero (OK) on success; a negated errno value on failure. + * + ****************************************************************************/ - flags = irqsave(); - oldcbr = inp(Z180_MMU_CBR); +int up_addrenv_destroy(task_addrenv_t addrenv) +{ + FAR struct z180_cbr_s *cbr = (FAR struct z180_cbr_s *)addrenv; - /* Check if the task has an address environment. */ + DEBUGASSERT(cbr); - if (tcb->xcp.cbr) - { - /* Yes.. Write the new CBR value into CBR register */ + /* Free the physical address space backing up the mapping */ - outp(Z180_MMU_CBR, tcb->xcp.cbr->cbr); - } +#ifdef CONFIG_GRAN_SINGLE + gran_free((FAR void *)cbr->cbr, cbr->pages); +#else + gran_free(g_physhandle, (FAR void *)cbr->cbr, cbr->pages); +#endif - irqrestore(flags); - return (FAR void *)oldcbr; + /* And make the CBR structure available for re-use */ + + z180_mmu_freecbr(cbr); + return OK; } /**************************************************************************** - * Name: up_addrenv_restore + * Name: up_addrenv_assign * * Description: - * Restore an address environment using a handle previously returned by - * up_addrenv_instantiate(). + * Assign an address environment to a TCB. * * Input Parameters: - * handle - A handle previously returned by up_addrenv_instantiate. + * addrenv - The representation of the task address environment previously + * returned by up_addrenv_create. + * tcb - The TCB of the task to receive the address environment. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ -int up_addrenv_restore(FAR void *handle) +int up_addrenv_assign(task_addrenv_t addrenv, FAR _TCB *tcb) { - /* Restore the CBR value */ + FAR struct z180_cbr_s *cbr = (FAR struct z180_cbr_s *)addrenv; + int ret; + + /* Make sure that there is no address environment in place on this TCB */ - outp(Z180_MMU_CBR, (uint8_t)handle); + DEBUGASSERT(cbr && tcb->xcp.cbr == NULL); + + /* Save the CBR strucure in the TCB. This is an atomic operation so no + * special precautions should be needed. + */ + + tcb->xcp.cbr = cbr; + return OK; +} + +/**************************************************************************** + * Name: up_addrenv_share + * + * Description: + * This function is called from the core scheduler logic when a thread + * is created that needs to share the address ennvironment of its parent + * task. In this case, the parent's address environment needs to be + * "cloned" for the child. + * + * Input Parameters: + * ptcb - The TCB of the parent task that has the address environment. + * ctcb - The TCB of the child thread needing the address environment. + * + * Returned Value: + * Zero (OK) on success; a negated errno value on failure. + * + ****************************************************************************/ + +int up_addrenv_share(FAR const _TCB *ptcb, FAR _TCB *ctcb) +{ + irqstate_t flags; + + /* Make sure that the child has no address environment. It is okay if + * if the parent does not have one. + */ + + DEBUGASSERT(ctcb->xcp.cbr == NULL); + + flags = irqsave(); + if (ptcb->xcp.cbr) + { + /* Clone the CBR by incrementing the reference counting and saving a + * copy in the child thread's TCB. + */ + + ptcb->xcp.cbr->crefs++; + ctcb->xcp.cbr = ptcb->xcp.cbr; + } + + irqrestore(flags); return OK; } @@ -407,7 +524,7 @@ int up_addrenv_release(FAR _TCB *tcb) cbr = tcb->xcp.cbr; if (cbr) { - /* Nullify the reference to the CBR structgure and decrement the number + /* Nullify the reference to the CBR structure and decrement the number * of references on the CBR. */ @@ -419,7 +536,7 @@ int up_addrenv_release(FAR _TCB *tcb) if (cbr->crefs <= 1) { - z180_mmu_freecbr(cbr); + up_addrenv_destroy(cbr); } else { -- cgit v1.2.3