MLK-23277: 8qm: Fix SW workaround for i.MX8QM TKT340553

Current workaround is looping uselessly on the address
range doing a  _tlbi(vmalle1is) which is harmful for
the system performance and buggy as the instruction is
flushing the entire TLB and there is no benefit of
redoing it more than once. Also fix missing barriers.

Signed-off-by: Nitin Garg <nitin.garg@nxp.com>
Signed-off-by: Marouen Ghodhbane <marouen.ghodhbane@nxp.com>
Reviewed-by: Jason Liu <jason.hui.liu@nxp.com>

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 6b0a7f0..c1ac9fe 100644 (file)
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -251,12 +251,15 @@ static inline void flush_tlb_mm(struct mm_struct *mm)
 
        dsb(ishst);
        if (TKT340553_SW_WORKAROUND) {
+               /* Flush the entire TLB */
                __tlbi(vmalle1is);
+               dsb(ish);
+               isb();
        } else {
                __tlbi(aside1is, asid);
                __tlbi_user(aside1is, asid);
+               dsb(ish);
        }
-       dsb(ish);
 }
 
 static inline void flush_tlb_page_nosync(struct vm_area_struct *vma,
@@ -266,7 +269,10 @@ static inline void flush_tlb_page_nosync(struct vm_area_struct *vma,
 
        dsb(ishst);
        if (TKT340553_SW_WORKAROUND) {
+               /* Flush the entire TLB */
                __tlbi(vmalle1is);
+               dsb(ish);
+               isb();
        } else {
                __tlbi(vale1is, addr);
                __tlbi_user(vale1is, addr);
@@ -296,7 +302,6 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
        unsigned long asid = ASID(vma->vm_mm);
        unsigned long addr;
        unsigned long pages;
-       unsigned long mask = (1 << 20) - 1;
 
        start = round_down(start, stride);
        end = round_up(end, stride);
@@ -316,7 +321,14 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
        }
 
        dsb(ishst);
-       mask <<= 24;
+
+       if (TKT340553_SW_WORKAROUND) {
+               /* Flush the entire TLB and exit */
+               __tlbi(vmalle1is);
+               dsb(ish);
+               isb();
+               return;
+       }
 
        /*
         * When the CPU does not support TLB range operations, flush the TLB
@@ -340,9 +352,7 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
                if (!system_supports_tlb_range() ||
                    pages % 2 == 1) {
                        addr = __TLBI_VADDR(start, asid);
-                       if (TKT340553_SW_WORKAROUND) {
-                               __tlbi(vmalle1is);
-                       } else if (last_level) {
+                       if (last_level) {
                                __tlbi_level(vale1is, addr, tlb_level);
                                __tlbi_user_level(vale1is, addr, tlb_level);
                        } else {
@@ -358,9 +368,7 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
                if (num >= 0) {
                        addr = __TLBI_VADDR_RANGE(start, asid, scale,
                                                  num, tlb_level);
-                       if (TKT340553_SW_WORKAROUND) {
-                               __tlbi(vmalle1is);
-                       } else if (last_level) {
+                       if (last_level) {
                                __tlbi(rvale1is, addr);
                                __tlbi_user(rvale1is, addr);
                        } else {
@@ -391,7 +399,8 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
 {
        unsigned long addr;
 
-       if ((end - start) > (MAX_TLBI_OPS * PAGE_SIZE)) {
+       if (((end - start) > (MAX_TLBI_OPS * PAGE_SIZE))
+           || (TKT340553_SW_WORKAROUND)) {
                flush_tlb_all();
                return;
        }
@@ -400,12 +409,8 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
        end = __TLBI_VADDR(end, 0);
 
        dsb(ishst);
-       for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12)) {
-               if (TKT340553_SW_WORKAROUND)
-                       __tlbi(vmalle1is);
-               else
-                       __tlbi(vaale1is, addr);
-       }
+       for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
+               __tlbi(vaale1is, addr);
        dsb(ish);
        isb();
 }
@@ -420,6 +425,7 @@ static inline void __flush_tlb_kernel_pgtable(unsigned long kaddr)
 
        dsb(ishst);
        if (TKT340553_SW_WORKAROUND)
+               /* Flush the entire TLB */
                __tlbi(vmalle1is);
        else
                __tlbi(vaae1is, addr);