[PATCH 4/9] dspbridge: remove custom mmu code from tiomap3430.c
From: Fernando Guzman Lugo
Date: Wed Jun 30 2010 - 20:12:39 EST
This patch removes all the custom mmu code remaining in
tiomap3430.c which is not needed anymore.
Signed-off-by: Fernando Guzman Lugo <x0095840@xxxxxx>
---
drivers/dsp/bridge/core/_tiomap.h | 1 -
drivers/dsp/bridge/core/tiomap3430.c | 470 ----------------------------------
2 files changed, 0 insertions(+), 471 deletions(-)
diff --git a/drivers/dsp/bridge/core/_tiomap.h b/drivers/dsp/bridge/core/_tiomap.h
index 4aa2358..c41fd8e 100644
--- a/drivers/dsp/bridge/core/_tiomap.h
+++ b/drivers/dsp/bridge/core/_tiomap.h
@@ -356,7 +356,6 @@ struct bridge_dev_context {
/* TC Settings */
bool tc_word_swap_on; /* Traffic Controller Word Swap */
- struct pg_table_attrs *pt_attrs;
u32 dsp_per_clks;
};
diff --git a/drivers/dsp/bridge/core/tiomap3430.c b/drivers/dsp/bridge/core/tiomap3430.c
index 88f5167..96cceea 100644
--- a/drivers/dsp/bridge/core/tiomap3430.c
+++ b/drivers/dsp/bridge/core/tiomap3430.c
@@ -105,56 +105,9 @@ static int bridge_dev_create(OUT struct bridge_dev_context
static int bridge_dev_ctrl(struct bridge_dev_context *dev_context,
u32 dw_cmd, IN OUT void *pargs);
static int bridge_dev_destroy(struct bridge_dev_context *dev_context);
-static u32 user_va2_pa(struct mm_struct *mm, u32 address);
-static int pte_update(struct bridge_dev_context *hDevContext, u32 pa,
- u32 va, u32 size,
- struct hw_mmu_map_attrs_t *map_attrs);
-static int pte_set(struct pg_table_attrs *pt, u32 pa, u32 va,
- u32 size, struct hw_mmu_map_attrs_t *attrs);
-static int mem_map_vmalloc(struct bridge_dev_context *hDevContext,
- u32 ul_mpu_addr, u32 ulVirtAddr,
- u32 ul_num_bytes,
- struct hw_mmu_map_attrs_t *hw_attrs);
bool wait_for_start(struct bridge_dev_context *dev_context, u32 dw_sync_addr);
-/* ----------------------------------- Globals */
-
-/* Attributes of L2 page tables for DSP MMU */
-struct page_info {
- u32 num_entries; /* Number of valid PTEs in the L2 PT */
-};
-
-/* Attributes used to manage the DSP MMU page tables */
-struct pg_table_attrs {
- spinlock_t pg_lock; /* Critical section object handle */
-
- u32 l1_base_pa; /* Physical address of the L1 PT */
- u32 l1_base_va; /* Virtual address of the L1 PT */
- u32 l1_size; /* Size of the L1 PT */
- u32 l1_tbl_alloc_pa;
- /* Physical address of Allocated mem for L1 table. May not be aligned */
- u32 l1_tbl_alloc_va;
- /* Virtual address of Allocated mem for L1 table. May not be aligned */
- u32 l1_tbl_alloc_sz;
- /* Size of consistent memory allocated for L1 table.
- * May not be aligned */
-
- u32 l2_base_pa; /* Physical address of the L2 PT */
- u32 l2_base_va; /* Virtual address of the L2 PT */
- u32 l2_size; /* Size of the L2 PT */
- u32 l2_tbl_alloc_pa;
- /* Physical address of Allocated mem for L2 table. May not be aligned */
- u32 l2_tbl_alloc_va;
- /* Virtual address of Allocated mem for L2 table. May not be aligned */
- u32 l2_tbl_alloc_sz;
- /* Size of consistent memory allocated for L2 table.
- * May not be aligned */
-
- u32 l2_num_pages; /* Number of allocated L2 PT */
- /* Array [l2_num_pages] of L2 PT info structs */
- struct page_info *pg_info;
-};
/*
* This Bridge driver's function interface table.
@@ -210,32 +163,6 @@ static struct bridge_drv_interface drv_interface_fxns = {
bridge_msg_set_queue_id,
};
-static inline void tlb_flush_all(const void __iomem *base)
-{
- __raw_writeb(__raw_readb(base + MMU_GFLUSH) | 1, base + MMU_GFLUSH);
-}
-
-static inline void flush_all(struct bridge_dev_context *dev_context)
-{
- if (dev_context->dw_brd_state == BRD_DSP_HIBERNATION ||
- dev_context->dw_brd_state == BRD_HIBERNATION)
- wake_dsp(dev_context, NULL);
-
- tlb_flush_all(dev_context->dw_dsp_mmu_base);
-}
-
-static void bad_page_dump(u32 pa, struct page *pg)
-{
- pr_emerg("DSPBRIDGE: MAP function: COUNT 0 FOR PA 0x%x\n", pa);
- pr_emerg("Bad page state in process '%s'\n"
- "page:%p flags:0x%0*lx mapping:%p mapcount:%d count:%d\n"
- "Backtrace:\n",
- current->comm, pg, (int)(2 * sizeof(unsigned long)),
- (unsigned long)pg->flags, pg->mapping,
- page_mapcount(pg), page_count(pg));
- dump_stack();
-}
-
/*
* ======== bridge_drv_entry ========
* purpose:
@@ -637,7 +564,6 @@ static int bridge_brd_stop(struct bridge_dev_context *hDevContext)
{
int status = 0;
struct bridge_dev_context *dev_context = hDevContext;
- struct pg_table_attrs *pt_attrs;
u32 dsp_pwr_state;
int clk_status;
struct dspbridge_platform_data *pdata =
@@ -677,15 +603,6 @@ static int bridge_brd_stop(struct bridge_dev_context *hDevContext)
dsp_wdt_enable(false);
- /* This is a good place to clear the MMU page tables as well */
- if (dev_context->pt_attrs) {
- pt_attrs = dev_context->pt_attrs;
- memset((u8 *) pt_attrs->l1_base_va, 0x00, pt_attrs->l1_size);
- memset((u8 *) pt_attrs->l2_base_va, 0x00, pt_attrs->l2_size);
- memset((u8 *) pt_attrs->pg_info, 0x00,
- (pt_attrs->l2_num_pages * sizeof(struct page_info)));
- }
-
/* Reset DSP */
(*pdata->dsp_prm_rmw_bits)(OMAP3430_RST1_IVA2, OMAP3430_RST1_IVA2,
OMAP3430_IVA2_MOD, RM_RSTCTRL);
@@ -725,7 +642,6 @@ static int bridge_brd_delete(struct bridge_dev_context *hDevContext)
{
int status = 0;
struct bridge_dev_context *dev_context = hDevContext;
- struct pg_table_attrs *pt_attrs;
int clk_status;
struct dspbridge_platform_data *pdata =
omap_dspbridge_dev->dev.platform_data;
@@ -747,15 +663,6 @@ static int bridge_brd_delete(struct bridge_dev_context *hDevContext)
dev_context->dw_brd_state = BRD_STOPPED; /* update board state */
- /* This is a good place to clear the MMU page tables as well */
- if (dev_context->pt_attrs) {
- pt_attrs = dev_context->pt_attrs;
- memset((u8 *) pt_attrs->l1_base_va, 0x00, pt_attrs->l1_size);
- memset((u8 *) pt_attrs->l2_base_va, 0x00, pt_attrs->l2_size);
- memset((u8 *) pt_attrs->pg_info, 0x00,
- (pt_attrs->l2_num_pages * sizeof(struct page_info)));
- }
-
/* Reset DSP */
(*pdata->dsp_prm_rmw_bits)(OMAP3430_RST1_IVA2, OMAP3430_RST1_IVA2,
OMAP3430_IVA2_MOD, RM_RSTCTRL);
@@ -836,10 +743,6 @@ static int bridge_dev_create(OUT struct bridge_dev_context
struct bridge_dev_context *dev_context = NULL;
s32 entry_ndx;
struct cfg_hostres *resources = pConfig;
- struct pg_table_attrs *pt_attrs;
- u32 pg_tbl_pa;
- u32 pg_tbl_va;
- u32 align_size;
struct drv_data *drv_datap = dev_get_drvdata(bridge);
/* Allocate and initialize a data structure to contain the bridge driver
@@ -871,97 +774,11 @@ static int bridge_dev_create(OUT struct bridge_dev_context
if (!dev_context->dw_dsp_base_addr)
status = -EPERM;
- pt_attrs = kzalloc(sizeof(struct pg_table_attrs), GFP_KERNEL);
- if (pt_attrs != NULL) {
- /* Assuming that we use only DSP's memory map
- * until 0x4000:0000 , we would need only 1024
- * L1 enties i.e L1 size = 4K */
- pt_attrs->l1_size = 0x1000;
- align_size = pt_attrs->l1_size;
- /* Align sizes are expected to be power of 2 */
- /* we like to get aligned on L1 table size */
- pg_tbl_va = (u32) mem_alloc_phys_mem(pt_attrs->l1_size,
- align_size, &pg_tbl_pa);
-
- /* Check if the PA is aligned for us */
- if ((pg_tbl_pa) & (align_size - 1)) {
- /* PA not aligned to page table size ,
- * try with more allocation and align */
- mem_free_phys_mem((void *)pg_tbl_va, pg_tbl_pa,
- pt_attrs->l1_size);
- /* we like to get aligned on L1 table size */
- pg_tbl_va =
- (u32) mem_alloc_phys_mem((pt_attrs->l1_size) * 2,
- align_size, &pg_tbl_pa);
- /* We should be able to get aligned table now */
- pt_attrs->l1_tbl_alloc_pa = pg_tbl_pa;
- pt_attrs->l1_tbl_alloc_va = pg_tbl_va;
- pt_attrs->l1_tbl_alloc_sz = pt_attrs->l1_size * 2;
- /* Align the PA to the next 'align' boundary */
- pt_attrs->l1_base_pa =
- ((pg_tbl_pa) +
- (align_size - 1)) & (~(align_size - 1));
- pt_attrs->l1_base_va =
- pg_tbl_va + (pt_attrs->l1_base_pa - pg_tbl_pa);
- } else {
- /* We got aligned PA, cool */
- pt_attrs->l1_tbl_alloc_pa = pg_tbl_pa;
- pt_attrs->l1_tbl_alloc_va = pg_tbl_va;
- pt_attrs->l1_tbl_alloc_sz = pt_attrs->l1_size;
- pt_attrs->l1_base_pa = pg_tbl_pa;
- pt_attrs->l1_base_va = pg_tbl_va;
- }
- if (pt_attrs->l1_base_va)
- memset((u8 *) pt_attrs->l1_base_va, 0x00,
- pt_attrs->l1_size);
-
- /* number of L2 page tables = DMM pool used + SHMMEM +EXTMEM +
- * L4 pages */
- pt_attrs->l2_num_pages = ((DMMPOOLSIZE >> 20) + 6);
- pt_attrs->l2_size = HW_MMU_COARSE_PAGE_SIZE *
- pt_attrs->l2_num_pages;
- align_size = 4; /* Make it u32 aligned */
- /* we like to get aligned on L1 table size */
- pg_tbl_va = (u32) mem_alloc_phys_mem(pt_attrs->l2_size,
- align_size, &pg_tbl_pa);
- pt_attrs->l2_tbl_alloc_pa = pg_tbl_pa;
- pt_attrs->l2_tbl_alloc_va = pg_tbl_va;
- pt_attrs->l2_tbl_alloc_sz = pt_attrs->l2_size;
- pt_attrs->l2_base_pa = pg_tbl_pa;
- pt_attrs->l2_base_va = pg_tbl_va;
-
- if (pt_attrs->l2_base_va)
- memset((u8 *) pt_attrs->l2_base_va, 0x00,
- pt_attrs->l2_size);
-
- pt_attrs->pg_info = kzalloc(pt_attrs->l2_num_pages *
- sizeof(struct page_info), GFP_KERNEL);
- dev_dbg(bridge,
- "L1 pa %x, va %x, size %x\n L2 pa %x, va "
- "%x, size %x\n", pt_attrs->l1_base_pa,
- pt_attrs->l1_base_va, pt_attrs->l1_size,
- pt_attrs->l2_base_pa, pt_attrs->l2_base_va,
- pt_attrs->l2_size);
- dev_dbg(bridge, "pt_attrs %p L2 NumPages %x pg_info %p\n",
- pt_attrs, pt_attrs->l2_num_pages, pt_attrs->pg_info);
- }
- if ((pt_attrs != NULL) && (pt_attrs->l1_base_va != 0) &&
- (pt_attrs->l2_base_va != 0) && (pt_attrs->pg_info != NULL))
- dev_context->pt_attrs = pt_attrs;
- else
- status = -ENOMEM;
-
if (DSP_SUCCEEDED(status)) {
- spin_lock_init(&pt_attrs->pg_lock);
dev_context->tc_word_swap_on = drv_datap->tc_wordswapon;
-
- /* Set the Clock Divisor for the DSP module */
- udelay(5);
/* MMU address is obtained from the host
* resources struct */
dev_context->dw_dsp_mmu_base = resources->dw_dmmu_base;
- }
- if (DSP_SUCCEEDED(status)) {
dev_context->hdev_obj = hdev_obj;
dev_context->ul_int_mask = 0;
/* Store current board state. */
@@ -970,23 +787,6 @@ static int bridge_dev_create(OUT struct bridge_dev_context
/* Return ptr to our device state to the DSP API for storage */
*ppDevContext = dev_context;
} else {
- if (pt_attrs != NULL) {
- kfree(pt_attrs->pg_info);
-
- if (pt_attrs->l2_tbl_alloc_va) {
- mem_free_phys_mem((void *)
- pt_attrs->l2_tbl_alloc_va,
- pt_attrs->l2_tbl_alloc_pa,
- pt_attrs->l2_tbl_alloc_sz);
- }
- if (pt_attrs->l1_tbl_alloc_va) {
- mem_free_phys_mem((void *)
- pt_attrs->l1_tbl_alloc_va,
- pt_attrs->l1_tbl_alloc_pa,
- pt_attrs->l1_tbl_alloc_sz);
- }
- }
- kfree(pt_attrs);
kfree(dev_context);
}
func_end:
@@ -1054,7 +854,6 @@ static int bridge_dev_ctrl(struct bridge_dev_context *dev_context,
*/
static int bridge_dev_destroy(struct bridge_dev_context *hDevContext)
{
- struct pg_table_attrs *pt_attrs;
int status = 0;
struct bridge_dev_context *dev_context = (struct bridge_dev_context *)
hDevContext;
@@ -1068,23 +867,6 @@ static int bridge_dev_destroy(struct bridge_dev_context *hDevContext)
/* first put the device to stop state */
bridge_brd_delete(dev_context);
- if (dev_context->pt_attrs) {
- pt_attrs = dev_context->pt_attrs;
- kfree(pt_attrs->pg_info);
-
- if (pt_attrs->l2_tbl_alloc_va) {
- mem_free_phys_mem((void *)pt_attrs->l2_tbl_alloc_va,
- pt_attrs->l2_tbl_alloc_pa,
- pt_attrs->l2_tbl_alloc_sz);
- }
- if (pt_attrs->l1_tbl_alloc_va) {
- mem_free_phys_mem((void *)pt_attrs->l1_tbl_alloc_va,
- pt_attrs->l1_tbl_alloc_pa,
- pt_attrs->l1_tbl_alloc_sz);
- }
- kfree(pt_attrs);
-
- }
if (dev_context->resources) {
host_res = dev_context->resources;
@@ -1315,258 +1097,6 @@ int user_to_dsp_unmap(struct iommu *mmu, u32 da)
}
/*
- * ======== user_va2_pa ========
- * Purpose:
- * This function walks through the page tables to convert a userland
- * virtual address to physical address
- */
-static u32 user_va2_pa(struct mm_struct *mm, u32 address)
-{
- pgd_t *pgd;
- pmd_t *pmd;
- pte_t *ptep, pte;
-
- pgd = pgd_offset(mm, address);
- if (!(pgd_none(*pgd) || pgd_bad(*pgd))) {
- pmd = pmd_offset(pgd, address);
- if (!(pmd_none(*pmd) || pmd_bad(*pmd))) {
- ptep = pte_offset_map(pmd, address);
- if (ptep) {
- pte = *ptep;
- if (pte_present(pte))
- return pte & PAGE_MASK;
- }
- }
- }
-
- return 0;
-}
-
-/*
- * ======== pte_update ========
- * This function calculates the optimum page-aligned addresses and sizes
- * Caller must pass page-aligned values
- */
-static int pte_update(struct bridge_dev_context *hDevContext, u32 pa,
- u32 va, u32 size,
- struct hw_mmu_map_attrs_t *map_attrs)
-{
- u32 i;
- u32 all_bits;
- u32 pa_curr = pa;
- u32 va_curr = va;
- u32 num_bytes = size;
- struct bridge_dev_context *dev_context = hDevContext;
- int status = 0;
- u32 page_size[] = { HW_PAGE_SIZE16MB, HW_PAGE_SIZE1MB,
- HW_PAGE_SIZE64KB, HW_PAGE_SIZE4KB
- };
-
- while (num_bytes && DSP_SUCCEEDED(status)) {
- /* To find the max. page size with which both PA & VA are
- * aligned */
- all_bits = pa_curr | va_curr;
-
- for (i = 0; i < 4; i++) {
- if ((num_bytes >= page_size[i]) && ((all_bits &
- (page_size[i] -
- 1)) == 0)) {
- status =
- pte_set(dev_context->pt_attrs, pa_curr,
- va_curr, page_size[i], map_attrs);
- pa_curr += page_size[i];
- va_curr += page_size[i];
- num_bytes -= page_size[i];
- /* Don't try smaller sizes. Hopefully we have
- * reached an address aligned to a bigger page
- * size */
- break;
- }
- }
- }
-
- return status;
-}
-
-/*
- * ======== pte_set ========
- * This function calculates PTE address (MPU virtual) to be updated
- * It also manages the L2 page tables
- */
-static int pte_set(struct pg_table_attrs *pt, u32 pa, u32 va,
- u32 size, struct hw_mmu_map_attrs_t *attrs)
-{
- u32 i;
- u32 pte_val;
- u32 pte_addr_l1;
- u32 pte_size;
- /* Base address of the PT that will be updated */
- u32 pg_tbl_va;
- u32 l1_base_va;
- /* Compiler warns that the next three variables might be used
- * uninitialized in this function. Doesn't seem so. Working around,
- * anyways. */
- u32 l2_base_va = 0;
- u32 l2_base_pa = 0;
- u32 l2_page_num = 0;
- int status = 0;
-
- l1_base_va = pt->l1_base_va;
- pg_tbl_va = l1_base_va;
- if ((size == HW_PAGE_SIZE64KB) || (size == HW_PAGE_SIZE4KB)) {
- /* Find whether the L1 PTE points to a valid L2 PT */
- pte_addr_l1 = hw_mmu_pte_addr_l1(l1_base_va, va);
- if (pte_addr_l1 <= (pt->l1_base_va + pt->l1_size)) {
- pte_val = *(u32 *) pte_addr_l1;
- pte_size = hw_mmu_pte_size_l1(pte_val);
- } else {
- return -EPERM;
- }
- spin_lock(&pt->pg_lock);
- if (pte_size == HW_MMU_COARSE_PAGE_SIZE) {
- /* Get the L2 PA from the L1 PTE, and find
- * corresponding L2 VA */
- l2_base_pa = hw_mmu_pte_coarse_l1(pte_val);
- l2_base_va =
- l2_base_pa - pt->l2_base_pa + pt->l2_base_va;
- l2_page_num =
- (l2_base_pa -
- pt->l2_base_pa) / HW_MMU_COARSE_PAGE_SIZE;
- } else if (pte_size == 0) {
- /* L1 PTE is invalid. Allocate a L2 PT and
- * point the L1 PTE to it */
- /* Find a free L2 PT. */
- for (i = 0; (i < pt->l2_num_pages) &&
- (pt->pg_info[i].num_entries != 0); i++)
- ;;
- if (i < pt->l2_num_pages) {
- l2_page_num = i;
- l2_base_pa = pt->l2_base_pa + (l2_page_num *
- HW_MMU_COARSE_PAGE_SIZE);
- l2_base_va = pt->l2_base_va + (l2_page_num *
- HW_MMU_COARSE_PAGE_SIZE);
- /* Endianness attributes are ignored for
- * HW_MMU_COARSE_PAGE_SIZE */
- status =
- hw_mmu_pte_set(l1_base_va, l2_base_pa, va,
- HW_MMU_COARSE_PAGE_SIZE,
- attrs);
- } else {
- status = -ENOMEM;
- }
- } else {
- /* Found valid L1 PTE of another size.
- * Should not overwrite it. */
- status = -EPERM;
- }
- if (DSP_SUCCEEDED(status)) {
- pg_tbl_va = l2_base_va;
- if (size == HW_PAGE_SIZE64KB)
- pt->pg_info[l2_page_num].num_entries += 16;
- else
- pt->pg_info[l2_page_num].num_entries++;
- dev_dbg(bridge, "PTE: L2 BaseVa %x, BasePa %x, PageNum "
- "%x, num_entries %x\n", l2_base_va,
- l2_base_pa, l2_page_num,
- pt->pg_info[l2_page_num].num_entries);
- }
- spin_unlock(&pt->pg_lock);
- }
- if (DSP_SUCCEEDED(status)) {
- dev_dbg(bridge, "PTE: pg_tbl_va %x, pa %x, va %x, size %x\n",
- pg_tbl_va, pa, va, size);
- dev_dbg(bridge, "PTE: endianism %x, element_size %x, "
- "mixed_size %x\n", attrs->endianism,
- attrs->element_size, attrs->mixed_size);
- status = hw_mmu_pte_set(pg_tbl_va, pa, va, size, attrs);
- }
-
- return status;
-}
-
-/* Memory map kernel VA -- memory allocated with vmalloc */
-static int mem_map_vmalloc(struct bridge_dev_context *dev_context,
- u32 ul_mpu_addr, u32 ulVirtAddr,
- u32 ul_num_bytes,
- struct hw_mmu_map_attrs_t *hw_attrs)
-{
- int status = 0;
- struct page *page[1];
- u32 i;
- u32 pa_curr;
- u32 pa_next;
- u32 va_curr;
- u32 size_curr;
- u32 num_pages;
- u32 pa;
- u32 num_of4k_pages;
- u32 temp = 0;
-
- /*
- * Do Kernel va to pa translation.
- * Combine physically contiguous regions to reduce TLBs.
- * Pass the translated pa to pte_update.
- */
- num_pages = ul_num_bytes / PAGE_SIZE; /* PAGE_SIZE = OS page size */
- i = 0;
- va_curr = ul_mpu_addr;
- page[0] = vmalloc_to_page((void *)va_curr);
- pa_next = page_to_phys(page[0]);
- while (DSP_SUCCEEDED(status) && (i < num_pages)) {
- /*
- * Reuse pa_next from the previous iteraion to avoid
- * an extra va2pa call
- */
- pa_curr = pa_next;
- size_curr = PAGE_SIZE;
- /*
- * If the next page is physically contiguous,
- * map it with the current one by increasing
- * the size of the region to be mapped
- */
- while (++i < num_pages) {
- page[0] =
- vmalloc_to_page((void *)(va_curr + size_curr));
- pa_next = page_to_phys(page[0]);
-
- if (pa_next == (pa_curr + size_curr))
- size_curr += PAGE_SIZE;
- else
- break;
-
- }
- if (pa_next == 0) {
- status = -ENOMEM;
- break;
- }
- pa = pa_curr;
- num_of4k_pages = size_curr / HW_PAGE_SIZE4KB;
- while (temp++ < num_of4k_pages) {
- get_page(PHYS_TO_PAGE(pa));
- pa += HW_PAGE_SIZE4KB;
- }
- status = pte_update(dev_context, pa_curr, ulVirtAddr +
- (va_curr - ul_mpu_addr), size_curr,
- hw_attrs);
- va_curr += size_curr;
- }
- if (DSP_SUCCEEDED(status))
- status = 0;
- else
- status = -EPERM;
-
- /*
- * In any case, flush the TLB
- * This is called from here instead from pte_update to avoid unnecessary
- * repetition while mapping non-contiguous physical regions of a virtual
- * region
- */
- flush_all(dev_context);
- dev_dbg(bridge, "%s status %x\n", __func__, status);
- return status;
-}
-
-/*
* ======== wait_for_start ========
* Wait for the singal from DSP that it has started, or time out.
*/
--
1.6.3.3
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